From b91da5d8bf6c9c41c91459ab85e90e3a39b372ec Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 12:04:14 +0100
Subject: [PATCH 01/90] Add SuperLU_dist to Spack package

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index f63cec81..27aadd6a 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -59,6 +59,7 @@ class FenicsDolfinx(CMakePackage):
     variant("slepc", default=False, description="SLEPc support")
     variant("adios2", default=False, description="ADIOS2 support")
     variant("petsc", default=False, description="PETSc support")
+    variant("superlu-dist", default=False, description="SuperLU_DIST support", when="@main")
 
     conflicts("~petsc", when="+slepc", msg="+slepc requires +petsc")
 
@@ -81,6 +82,9 @@ class FenicsDolfinx(CMakePackage):
     depends_on("adios2@2.8.1:", when="@0.9: +adios2")
     depends_on("adios2+mpi", when="+adios2")
 
+    depends_on("superlu-dist+parmetis", when="+superlu_dist partitioners=parmetis")
+    depends_on("superlu-dist~parmetis", when="+superlu-dist partitioners=~parmetis")
+
     for ver in ("main", "0.10", "0.9", "0.8", "0.7", "0.6"):
         depends_on(f"fenics-ufcx@{ver}", when=f"@{ver}")
         depends_on(f"fenics-basix@{ver}", when=f"@{ver}")

From 391c2c648a3f42e22ea16829713671d903511f3f Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 12:18:08 +0100
Subject: [PATCH 02/90] Add comment

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 27aadd6a..84bceccf 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -82,6 +82,7 @@ class FenicsDolfinx(CMakePackage):
     depends_on("adios2@2.8.1:", when="@0.9: +adios2")
     depends_on("adios2+mpi", when="+adios2")
 
+    # If asked for DOLFINx without Parmetis, don't build SuperLU_DIST with it.
     depends_on("superlu-dist+parmetis", when="+superlu_dist partitioners=parmetis")
     depends_on("superlu-dist~parmetis", when="+superlu-dist partitioners=~parmetis")
 

From b97d38f8c87b33a83d5edd88f83122b584fad87b Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 14:54:34 +0100
Subject: [PATCH 03/90] Fix and add strict check

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 84bceccf..e7db6d75 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -83,7 +83,7 @@ class FenicsDolfinx(CMakePackage):
     depends_on("adios2+mpi", when="+adios2")
 
     # If asked for DOLFINx without Parmetis, don't build SuperLU_DIST with it.
-    depends_on("superlu-dist+parmetis", when="+superlu_dist partitioners=parmetis")
+    depends_on("superlu-dist+parmetis", when="+superlu-dist partitioners=parmetis")
     depends_on("superlu-dist~parmetis", when="+superlu-dist partitioners=~parmetis")
 
     for ver in ("main", "0.10", "0.9", "0.8", "0.7", "0.6"):
@@ -105,4 +105,5 @@ def cmake_args(self):
             self.define("DOLFINX_ENABLE_KAHIP", "partitioners=kahip" in self.spec),
             self.define("DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec),
             self.define("DOLFINX_ENABLE_SCOTCH", "partitioners=scotch" in self.spec),
+            self.define("DOLFINX_ENABLE_SUPERLU_DIST", "superlu_dist" in self.spec),
         ]

From 7b92c4b9d9e024a0357b9e271c95479fa2f6bc04 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 15:00:27 +0100
Subject: [PATCH 04/90] Formatting

---
 .../fenics/packages/fenics_dolfinx/package.py | 39 ++++++++++++++-----
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index e7db6d75..91623ed6 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -2,9 +2,8 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack_repo.builtin.build_systems.cmake import CMakePackage
-
 from spack.package import *
+from spack_repo.builtin.build_systems.cmake import CMakePackage
 
 
 class FenicsDolfinx(CMakePackage):
@@ -17,15 +16,31 @@ class FenicsDolfinx(CMakePackage):
     license("LGPL-3.0-or-later")
 
     version("main", branch="main", no_cache=True)
-    version("0.10.0.post4", sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605")
     version(
-        "0.10.0.post2", sha256="eae83794fee8141c80c59c03a2f4ac208af2b62c8f36e5d19c93e0d279029f52"
+        "0.10.0.post4",
+        sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605",
+    )
+    version(
+        "0.10.0.post2",
+        sha256="eae83794fee8141c80c59c03a2f4ac208af2b62c8f36e5d19c93e0d279029f52",
+    )
+    version(
+        "0.9.0",
+        sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1",
+    )
+    version(
+        "0.8.0",
+        sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9",
     )
-    version("0.9.0", sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1")
-    version("0.8.0", sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9")
     with default_args(deprecated=True):
-        version("0.7.2", sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b")
-        version("0.6.0", sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80")
+        version(
+            "0.7.2",
+            sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b",
+        )
+        version(
+            "0.6.0",
+            sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80",
+        )
 
     patch("0.8-boost-filesystem.patch", when="@0.8")
 
@@ -59,7 +74,9 @@ class FenicsDolfinx(CMakePackage):
     variant("slepc", default=False, description="SLEPc support")
     variant("adios2", default=False, description="ADIOS2 support")
     variant("petsc", default=False, description="PETSc support")
-    variant("superlu-dist", default=False, description="SuperLU_DIST support", when="@main")
+    variant(
+        "superlu-dist", default=False, description="SuperLU_DIST support", when="@main"
+    )
 
     conflicts("~petsc", when="+slepc", msg="+slepc requires +petsc")
 
@@ -103,7 +120,9 @@ def cmake_args(self):
             self.define_from_variant("DOLFINX_ENABLE_ADIOS2", "adios2"),
             self.define("DOLFINX_UFCX_PYTHON", False),
             self.define("DOLFINX_ENABLE_KAHIP", "partitioners=kahip" in self.spec),
-            self.define("DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec),
+            self.define(
+                "DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec
+            ),
             self.define("DOLFINX_ENABLE_SCOTCH", "partitioners=scotch" in self.spec),
             self.define("DOLFINX_ENABLE_SUPERLU_DIST", "superlu_dist" in self.spec),
         ]

From 72dbbba9c1821c638f37e0e6ddc6011a78b791d5 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 15:14:40 +0100
Subject: [PATCH 05/90] Remove complexity

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 91623ed6..8d8baee7 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -99,9 +99,7 @@ class FenicsDolfinx(CMakePackage):
     depends_on("adios2@2.8.1:", when="@0.9: +adios2")
     depends_on("adios2+mpi", when="+adios2")
 
-    # If asked for DOLFINx without Parmetis, don't build SuperLU_DIST with it.
-    depends_on("superlu-dist+parmetis", when="+superlu-dist partitioners=parmetis")
-    depends_on("superlu-dist~parmetis", when="+superlu-dist partitioners=~parmetis")
+    depends_on("superlu-dist", when="+superlu-dist")
 
     for ver in ("main", "0.10", "0.9", "0.8", "0.7", "0.6"):
         depends_on(f"fenics-ufcx@{ver}", when=f"@{ver}")

From 738b0292e98a2c30e8d27e1b1bcf40f8dd241226 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 30 Jan 2026 15:19:53 +0100
Subject: [PATCH 06/90] Reduce slightly mad number of combos

---
 .github/workflows/spack-matrix.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 6810c6c7..262bc529 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -58,7 +58,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer", "partitioners=kahip,parmetis,scotch", "+petsc +slepc +adios2"]
+        variant: ["build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"]
         compiler: ["gcc@13", "clang@18"]
         exclude:
           # kahip does not support clang
@@ -80,7 +80,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        compiler: ["gcc@13", "clang@18"]
+        compiler: ["gcc@13"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -135,7 +135,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer", "+petsc4py +slepc4py"]
+        variant: ["build_type=Developer +petsc4py +slepc4py"]
         compiler: ["gcc@13", "clang@18"]
         python-version: ["3.10", "3.11", "3.12", "3.13"]
     steps:

From 2fa928572c0a7d51481f254389ec1cd5d283de93 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 16:20:50 +0100
Subject: [PATCH 07/90] Fix typo.

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 8d8baee7..5b707521 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -122,5 +122,5 @@ def cmake_args(self):
                 "DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec
             ),
             self.define("DOLFINX_ENABLE_SCOTCH", "partitioners=scotch" in self.spec),
-            self.define("DOLFINX_ENABLE_SUPERLU_DIST", "superlu_dist" in self.spec),
+            self.define("DOLFINX_ENABLE_SUPERLU_DIST", "superlu-dist" in self.spec),
         ]

From f3d0f3f35b9e713ee1ddf1cb09867cb93ba9430e Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 16:57:11 +0100
Subject: [PATCH 08/90] Simplify and add superlu-dist variant test on main

---
 .github/actions/test-package/action.yml | 15 +++--------
 .github/workflows/spack-matrix.yml      | 33 ++++++++++++++++---------
 2 files changed, 25 insertions(+), 23 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 340a7cb6..b9ec8234 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -5,11 +5,6 @@ inputs:
     description: 'Spack spec syntax'
     required: true
     type: string
-  python-version:
-    description: 'Python version'
-    required: false
-    type: string
-    default: '3.13'
 runs:
   using: "composite"
   steps:
@@ -21,7 +16,7 @@ runs:
 
     - uses: actions/setup-python@v6
       with:
-        python-version: ${{ inputs.python-version }}
+        python-version: 3.13
 
     - name: Set up spack
       uses: spack/setup-spack@v2
@@ -30,14 +25,12 @@ runs:
         color: true
         path: spack
 
-    - name: Install gcc-13 (default)
+    - name: Install gcc
       shell: sh
-      if: contains(inputs.spec, 'gcc@13') || (! contains(inputs.spec, 'clang') && ! contains(inputs.spec, 'gcc'))
       run: apt-get install -y g++ gcc gfortran build-essential
 
     - name: Install clang-18
       shell: sh
-      if: contains(inputs.spec, 'clang@18')
       run: apt-get install -y clang-18 gfortran
 
     - name: Add repos
@@ -69,7 +62,7 @@ runs:
     - name: Concretize
       shell: spack-bash {0}
       run: spack -e ./env concretize -j 4
-    
+
     - name: Install
       shell: spack-bash {0}
       run: >
@@ -81,5 +74,5 @@ runs:
       if: success() || failure()
       uses: actions/upload-artifact@v4
       with:
-        name: ${{ inputs.spec }}-${{ inputs.python-version }}-log
+        name: ${{ inputs.spec }}-log
         path: log.xml
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 262bc529..1dc6828c 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -41,7 +41,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["build_type=Developer"]
-        compiler: ["gcc@13", "clang@18"]
+        compiler: ["gcc", "clang"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -58,12 +58,16 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"]
-        compiler: ["gcc@13", "clang@18"]
+        variant: ["build_type=Developer", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"]
+        compiler: ["gcc", "clang"]
         exclude:
           # kahip does not support clang
-          - variant: "partitioners=kahip,parmetis,scotch"
-            compiler: "clang@18"
+          - variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
+            compiler: "clang"
+        include:
+          # test native superlu-dist support
+          version: "main"
+          variant: "build_type=Developer +superlu-dist"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -80,7 +84,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        compiler: ["gcc@13"]
+        compiler: ["gcc"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -98,7 +102,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["", "+ufl"]
-        compiler: ["gcc@13", "clang@18"]
+        compiler: ["gcc", "clang"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -136,17 +140,22 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["build_type=Developer +petsc4py +slepc4py"]
-        compiler: ["gcc@13", "clang@18"]
+        compiler: ["gcc", "clang"]
         python-version: ["3.10", "3.11", "3.12", "3.13"]
+      include:
+        # test new native superlu-dist support
+        version: "main"
+        variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
+        compiler: "gcc"
+        python-version: "3.13"
     steps:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          python-version: ${{ matrix.python-version }}
-      # workaround for https://github.com/spack/spack/issues/29447
+          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+      # Workaround for https://github.com/spack/spack/issues/29447
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0 (at least for dolfinx @:0.9)
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
@@ -182,7 +191,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-ffcx@${{ matrix.version }}
-      # workaround for https://github.com/spack/spack/issues/29447
+      # Workaround for https://github.com/spack/spack/issues/29447
       # we do not run numba based tests here due to disk-space constraints
       # 0.8 broken
       - name: Run tests

From 1efbf04cf0e33b43f2201cde7a0f77f9e29c814a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 17:42:14 +0100
Subject: [PATCH 09/90] Fix.

---
 .github/workflows/spack-matrix.yml | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 1dc6828c..e59d91e5 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,12 +62,13 @@ jobs:
         compiler: ["gcc", "clang"]
         exclude:
           # kahip does not support clang
-          - variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
-            compiler: "clang"
+          variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
+          compiler: "clang"
         include:
           # test native superlu-dist support
           version: "main"
           variant: "build_type=Developer +superlu-dist"
+          compiler: "gcc"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -142,12 +143,12 @@ jobs:
         variant: ["build_type=Developer +petsc4py +slepc4py"]
         compiler: ["gcc", "clang"]
         python-version: ["3.10", "3.11", "3.12", "3.13"]
-      include:
-        # test new native superlu-dist support
-        version: "main"
-        variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
-        compiler: "gcc"
-        python-version: "3.13"
+        include:
+          # test new native superlu-dist support
+          version: "main"
+          variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
+          compiler: "gcc"
+          python-version: "3.13"
     steps:
       - uses: actions/checkout@v5
         with:

From 243317dca777cf4ba51b694531faeccc2777af68 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 17:44:35 +0100
Subject: [PATCH 10/90] Fix

---
 .github/workflows/spack-matrix.yml | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index e59d91e5..87178313 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,13 +62,13 @@ jobs:
         compiler: ["gcc", "clang"]
         exclude:
           # kahip does not support clang
-          variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
-          compiler: "clang"
+          - variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
+            compiler: "clang"
         include:
           # test native superlu-dist support
-          version: "main"
-          variant: "build_type=Developer +superlu-dist"
-          compiler: "gcc"
+          - version: "main"
+            variant: "build_type=Developer +superlu-dist"
+            compiler: "gcc"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -145,10 +145,10 @@ jobs:
         python-version: ["3.10", "3.11", "3.12", "3.13"]
         include:
           # test new native superlu-dist support
-          version: "main"
-          variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
-          compiler: "gcc"
-          python-version: "3.13"
+          - version: "main"
+            variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
+            compiler: "gcc"
+            python-version: "3.13"
     steps:
       - uses: actions/checkout@v5
         with:

From 03ae8f9613cc0c073a382f6160e9e210c86ada82 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 18:03:22 +0100
Subject: [PATCH 11/90] Tidy.

---
 .github/workflows/spack-matrix.yml | 27 ++++++++++++---------------
 1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 87178313..1712ab84 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -7,7 +7,7 @@ on:
   pull_request:
   workflow_dispatch:
   schedule:
-    - cron: "0 2 * * MON" # weekly, mondays 2am
+    - cron: "0 2 * * MON" # weekly, Mondays 0200
 
 jobs:
   style-check:
@@ -111,8 +111,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-      # workaround for https://github.com/spack/spack/issues/29447
-      - name: Run tests (> 0.8)
+      - name: Run tests
         if: ${{ matrix.version != '0.8' && contains(matrix.variant, '+ufl') }}
         shell: spack-bash {0}
         run: |
@@ -121,8 +120,8 @@ jobs:
           spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           pytest test/
-      # 0.8 holds one broken test case
-      - name: Run tests (0.8)
+      # NOTE: 0.8 has test_all_elements_included broken
+      - name: Run tests
         if: ${{ matrix.version == '0.8' && contains(matrix.variant, '+ufl') }}
         shell: spack-bash {0}
         run: |
@@ -144,7 +143,7 @@ jobs:
         compiler: ["gcc", "clang"]
         python-version: ["3.10", "3.11", "3.12", "3.13"]
         include:
-          # test new native superlu-dist support
+          # Test new native superlu-dist support
           - version: "main"
             variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
             compiler: "gcc"
@@ -156,8 +155,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-      # Workaround for https://github.com/spack/spack/issues/29447
-      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0 (at least for dolfinx @:0.9)
+      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
         shell: spack-bash {0}
@@ -166,16 +164,18 @@ jobs:
           spack install --add py-pytest@8.4 py-scipy
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          pytest python/test/unit -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance"
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          mpiexec -np 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest@8.4 py-scipy
+          spack install --add py-pytest py-scipy
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          pytest python/test/unit -m "not petsc4py and not adios2" -k "not test_cffi_expression"
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
+          mpiexec -np 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
 
   py-fenics-ffcx:
     needs: style-check
@@ -192,9 +192,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-ffcx@${{ matrix.version }}
-      # Workaround for https://github.com/spack/spack/issues/29447
-      # we do not run numba based tests here due to disk-space constraints
-      # 0.8 broken
+      # NOTE: ffcx version 0.8 currently broken
       - name: Run tests
         if: ${{ matrix.version != '0.8' }}
         shell: spack-bash {0}
@@ -220,7 +218,6 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-ufl@${{ matrix.version }}
-      # workaround for https://github.com/spack/spack/issues/29447
       - name: Run tests
         shell: spack-bash {0}
         run: |

From ebcbe7c5d3350ebf1789d2cc4e1a611a62c8709a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 21:35:51 +0100
Subject: [PATCH 12/90] More tweaks.

---
 .github/workflows/spack-matrix.yml | 40 +++++++++++++++---------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 1712ab84..b119fb43 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -41,7 +41,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["build_type=Developer"]
-        compiler: ["gcc", "clang"]
+        compiler: ["gcc@13", "clang@18"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -59,16 +59,16 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["build_type=Developer", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"]
-        compiler: ["gcc", "clang"]
+        compiler: ["gcc@13", "clang@18"]
         exclude:
           # kahip does not support clang
           - variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
-            compiler: "clang"
+            compiler: "clang@18"
         include:
           # test native superlu-dist support
           - version: "main"
             variant: "build_type=Developer +superlu-dist"
-            compiler: "gcc"
+            compiler: "gcc@13"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -85,7 +85,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        compiler: ["gcc"]
+        compiler: ["gcc@13"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -103,7 +103,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["", "+ufl"]
-        compiler: ["gcc", "clang"]
+        compiler: ["gcc@13", "clang@18"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -119,7 +119,7 @@ jobs:
           spack install --add py-pytest py-sympy
           spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          pytest test/
+          python -m pytest test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
         if: ${{ matrix.version == '0.8' && contains(matrix.variant, '+ufl') }}
@@ -129,7 +129,7 @@ jobs:
           spack install --add py-pytest py-sympy
           spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          pytest test/ -k "not test_all_elements_included" 
+          python -m pytest -k "not test_all_elements_included" test/
 
   py-fenics-dolfinx:
     needs: style-check
@@ -140,13 +140,13 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         variant: ["build_type=Developer +petsc4py +slepc4py"]
-        compiler: ["gcc", "clang"]
-        python-version: ["3.10", "3.11", "3.12", "3.13"]
+        compiler: ["gcc@13", "clang@18"]
+        python-version: ["3.12", "3.13"]
         include:
           # Test new native superlu-dist support
           - version: "main"
             variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
-            compiler: "gcc"
+            compiler: "gcc@13"
             python-version: "3.13"
     steps:
       - uses: actions/checkout@v5
@@ -161,19 +161,19 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest@8.4 py-scipy
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-          mpiexec -np 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest py-scipy
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack install --add py-pytest py-scipy py-pytest-xdist
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
           mpiexec -np 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
 
@@ -201,7 +201,7 @@ jobs:
           spack install --add py-pytest py-sympy
           spack stage py-fenics-ffcx@${{ matrix.version }}
           spack cd py-fenics-ffcx@${{ matrix.version }}
-          pytest test/
+          python -m pytest test/
 
   py-fenics-ufl:
     needs: style-check
@@ -225,4 +225,4 @@ jobs:
           spack install --add py-pytest
           spack stage py-fenics-ufl@${{ matrix.version }}
           spack cd py-fenics-ufl@${{ matrix.version }}
-          pytest test/
+          python -m pytest test/

From d1ed073d456a2735bd38eef541ea5243722e7903 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:34:39 +0100
Subject: [PATCH 13/90] Build with MUMPS and install test Python with right
 Python version.

---
 .github/workflows/spack-matrix.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index b119fb43..13302bb2 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -139,7 +139,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer +petsc4py +slepc4py"]
+        variant: ["build_type=Developer +petsc4py +slepc4py ^petsc+mumps"]
         compiler: ["gcc@13", "clang@18"]
         python-version: ["3.12", "3.13"]
         include:
@@ -147,7 +147,7 @@ jobs:
           - version: "main"
             variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
             compiler: "gcc@13"
-            python-version: "3.13"
+            python-version: "3.11"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -161,7 +161,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist
+          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
@@ -171,7 +171,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest py-scipy py-pytest-xdist
+          spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit

From b780a2ff6f319c8aaa87352c7f242cac37fcaaf1 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:49:24 +0100
Subject: [PATCH 14/90] More pytest-xdist

---
 .github/workflows/spack-matrix.yml | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 13302bb2..55b5e882 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -116,20 +116,20 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest py-sympy
+          spack install --add py-pytest py-sympy py-pytest-xdist
           spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          python -m pytest test/
+          python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
         if: ${{ matrix.version == '0.8' && contains(matrix.variant, '+ufl') }}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest py-sympy
+          spack install --add py-pytest py-sympy py-pytest-xdist
           spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          python -m pytest -k "not test_all_elements_included" test/
+          python -m pytest -n auto -k "not test_all_elements_included" test/
 
   py-fenics-dolfinx:
     needs: style-check
@@ -139,7 +139,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer +petsc4py +slepc4py ^petsc+mumps"]
+        variant: ["build_type=Developer +petsc4py +slepc4py ^petsc+mumps ^fenics-dolfinx+adios2"]
         compiler: ["gcc@13", "clang@18"]
         python-version: ["3.12", "3.13"]
         include:
@@ -156,6 +156,7 @@ jobs:
         with:
           spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
+      # TODO: Get this to run petsc4py tests
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
         shell: spack-bash {0}
@@ -198,10 +199,10 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest py-sympy
+          spack install --add py-pytest py-sympy py-pytest-xdist
           spack stage py-fenics-ffcx@${{ matrix.version }}
           spack cd py-fenics-ffcx@${{ matrix.version }}
-          python -m pytest test/
+          python -m pytest -n auto test/
 
   py-fenics-ufl:
     needs: style-check
@@ -222,7 +223,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-pytest
+          spack install --add py-pytest py-pytest-xdist
           spack stage py-fenics-ufl@${{ matrix.version }}
           spack cd py-fenics-ufl@${{ matrix.version }}
-          python -m pytest test/
+          python -m pytest -n auto test/

From e0c9f867468c312fea75a4210e3e82fcf490c107 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:51:51 +0100
Subject: [PATCH 15/90] Try running petsc4py and adios2 tests

---
 .github/workflows/spack-matrix.yml | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 55b5e882..c4903fb6 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -156,7 +156,6 @@ jobs:
         with:
           spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
-      # TODO: Get this to run petsc4py tests
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
         shell: spack-bash {0}
@@ -165,8 +164,8 @@ jobs:
           spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          mpiexec -n 3 python -m pytest -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
         shell: spack-bash {0}
@@ -175,8 +174,8 @@ jobs:
           spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
-          mpiexec -np 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression" python/test/unit
+          python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
+          mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 
   py-fenics-ffcx:
     needs: style-check

From eec80dabb4b2defb7d5795cb0bafcb8de8f11de0 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:54:56 +0100
Subject: [PATCH 16/90] UFCx is unlicense

---
 spack_repo/fenics/packages/fenics_ufcx/package.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index c60b26e9..011b78cb 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -17,7 +17,7 @@ class FenicsUfcx(CMakePackage):
     url = "https://github.com/FEniCS/ffcx/archive/v0.4.2.tar.gz"
     maintainers("ma595", "jhale", "garth-wells", "chrisrichardson")
 
-    license("LGPL-3.0-or-later")
+    license("The Unlicense")
 
     version("main", branch="main", no_cache=True)
     version("0.10.0", sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9")

From c6419f91e59092dce6d111dc342e7bf671d354a8 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:55:31 +0100
Subject: [PATCH 17/90] Short version

---
 spack_repo/fenics/packages/fenics_ufcx/package.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index 011b78cb..433bc49b 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -17,7 +17,7 @@ class FenicsUfcx(CMakePackage):
     url = "https://github.com/FEniCS/ffcx/archive/v0.4.2.tar.gz"
     maintainers("ma595", "jhale", "garth-wells", "chrisrichardson")
 
-    license("The Unlicense")
+    license("Unlicense")
 
     version("main", branch="main", no_cache=True)
     version("0.10.0", sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9")

From 9b4ea779aded861a9b5fd867d90d4ffcf9bbacd4 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 22:59:29 +0100
Subject: [PATCH 18/90] Black

---
 .../fenics/packages/fenics_ufcx/package.py    | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index 433bc49b..b47773a7 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -20,12 +20,27 @@ class FenicsUfcx(CMakePackage):
     license("Unlicense")
 
     version("main", branch="main", no_cache=True)
-    version("0.10.0", sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9")
-    version("0.9.0", sha256="afa517272a3d2249f513cb711c50b77cf8368dd0b8f5ea4b759142229204a448")
-    version("0.8.0", sha256="8a854782dbd119ec1c23c4522a2134d5281e7f1bd2f37d64489f75da055282e3")
+    version(
+        "0.10.0",
+        sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9",
+    )
+    version(
+        "0.9.0",
+        sha256="afa517272a3d2249f513cb711c50b77cf8368dd0b8f5ea4b759142229204a448",
+    )
+    version(
+        "0.8.0",
+        sha256="8a854782dbd119ec1c23c4522a2134d5281e7f1bd2f37d64489f75da055282e3",
+    )
     with default_args(deprecated=True):
-        version("0.7.0", sha256="7f3c3ca91d63ce7831d37799cc19d0551bdcd275bdfa4c099711679533dd1c71")
-        version("0.6.0", sha256="076fad61d406afffd41019ae1abf6da3f76406c035c772abad2156127667980e")
+        version(
+            "0.7.0",
+            sha256="7f3c3ca91d63ce7831d37799cc19d0551bdcd275bdfa4c099711679533dd1c71",
+        )
+        version(
+            "0.6.0",
+            sha256="076fad61d406afffd41019ae1abf6da3f76406c035c772abad2156127667980e",
+        )
 
     depends_on("cmake@3.19:", type="build")
     depends_on("c", type="build")

From 17f55cfdba031bf1e453497290e05b3f5fe5768f Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 23:00:02 +0100
Subject: [PATCH 19/90] Fix

---
 spack_repo/fenics/packages/fenics_ufcx/package.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index b47773a7..5127071f 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -2,9 +2,8 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack_repo.builtin.build_systems.cmake import CMakePackage
-
 from spack.package import *
+from spack_repo.builtin.build_systems.cmake import CMakePackage
 
 
 class FenicsUfcx(CMakePackage):

From b772eb369f4ec3ecb165cd7124e5a5fa0e6a7849 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 23:14:46 +0100
Subject: [PATCH 20/90] Make sure compiler variant applies to base target - let
 Spack decide on others.

---
 .github/workflows/spack-matrix.yml | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index c4903fb6..96c8dfc1 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -48,7 +48,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spec: fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
 
   fenics-dolfinx:
     needs: style-check
@@ -75,8 +75,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-
+          spec: fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
   fenics-ufcx:
     needs: style-check
     runs-on: ubuntu-latest
@@ -117,8 +116,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack stage py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spack cd py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
           python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
@@ -127,8 +126,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack stage py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spack cd py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
           python -m pytest -n auto -k "not test_all_elements_included" test/
 
   py-fenics-dolfinx:
@@ -154,7 +153,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spec: py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
@@ -162,8 +161,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
           mpiexec -n 3 python -m pytest -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
@@ -172,8 +171,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
           mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 

From 842fbeacdc79a087e6b4156968a2023aa8c08da9 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 9 Feb 2026 23:18:53 +0100
Subject: [PATCH 21/90] The way compiler is being added to spec is problematic.

---
 .github/workflows/spack-matrix.yml | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 96c8dfc1..c4903fb6 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -48,7 +48,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spec: fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
 
   fenics-dolfinx:
     needs: style-check
@@ -75,7 +75,8 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+
   fenics-ufcx:
     needs: style-check
     runs-on: ubuntu-latest
@@ -116,8 +117,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
-          spack cd py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
@@ -126,8 +127,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
-          spack cd py-fenics-basix@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }}
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
           python -m pytest -n auto -k "not test_all_elements_included" test/
 
   py-fenics-dolfinx:
@@ -153,7 +154,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
+          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
@@ -161,8 +162,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
           mpiexec -n 3 python -m pytest -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
@@ -171,8 +172,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} %${{ matrix.compiler }} ${{ matrix.variant }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
           mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 

From 7d77bf49d5da12d0fefcba285b96c54470c5e036 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 07:58:15 +0100
Subject: [PATCH 22/90] Use spec directly - gives more control.

---
 .github/workflows/spack-matrix.yml | 58 ++++++++++++------------------
 1 file changed, 22 insertions(+), 36 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index c4903fb6..2e7a39de 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -40,15 +40,14 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer"]
-        compiler: ["gcc@13", "clang@18"]
+        spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
     steps:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spec: fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
 
   fenics-dolfinx:
     needs: style-check
@@ -58,24 +57,14 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"]
-        compiler: ["gcc@13", "clang@18"]
-        exclude:
-          # kahip does not support clang
-          - variant: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2"
-            compiler: "clang@18"
-        include:
-          # test native superlu-dist support
-          - version: "main"
-            variant: "build_type=Developer +superlu-dist"
-            compiler: "gcc@13"
+        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18"]
     steps:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spec: fenics-dolfinx@${{ matrix.version }} %${{ matrix.spec }}
 
   fenics-ufcx:
     needs: style-check
@@ -85,14 +74,14 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        compiler: ["gcc@13"]
+        spec: ["%gcc@13"]
     steps:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-ufcx@${{ matrix.version }} %${{ matrix.compiler }}
+          spec: fenics-ufcx@${{ matrix.version }} ${{ matrix.spec }}
 
   py-fenics-basix:
     needs: style-check
@@ -102,8 +91,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["", "+ufl"]
-        compiler: ["gcc@13", "clang@18"]
+        spec: ["+ufl %gcc@13", "%clang@18"] 
     steps:
       - uses: actions/checkout@v5
         with:
@@ -117,8 +105,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
           python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
@@ -127,8 +115,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
           python -m pytest -n auto -k "not test_all_elements_included" test/
 
   py-fenics-dolfinx:
@@ -139,22 +127,20 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        variant: ["build_type=Developer +petsc4py +slepc4py ^petsc+mumps ^fenics-dolfinx+adios2"]
-        compiler: ["gcc@13", "clang@18"]
-        python-version: ["3.12", "3.13"]
+        python-version: ["3.10", "3.13"]
+        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+               "build_type=Developer %clang@18"]
+        # Test new superlu-dist variant
         include:
-          # Test new native superlu-dist support
-          - version: "main"
-            variant: "build_type=Developer ^fenics-dolfinx+superlu-dist"
-            compiler: "gcc@13"
-            python-version: "3.11"
+          version: "main"
+          spec: "build_type=Developer +superlu-dist %clang@18"
     steps:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spec: py-fenics-dolfinx@${{ matrix.version }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
@@ -162,8 +148,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
           mpiexec -n 3 python -m pytest -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
@@ -172,8 +158,8 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }} ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
           mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 

From f64fc8b668d5e1baaa612d8058b5d596ffc029f6 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:00:07 +0100
Subject: [PATCH 23/90] Fix.

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 2e7a39de..d36d75b6 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -132,7 +132,7 @@ jobs:
                "build_type=Developer %clang@18"]
         # Test new superlu-dist variant
         include:
-          version: "main"
+          - version: "main"
           spec: "build_type=Developer +superlu-dist %clang@18"
     steps:
       - uses: actions/checkout@v5

From b53196f8b3f602b30ee597d213b2fe1e21442ae6 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:00:40 +0100
Subject: [PATCH 24/90] Fix

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index d36d75b6..d97e7d88 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -133,7 +133,7 @@ jobs:
         # Test new superlu-dist variant
         include:
           - version: "main"
-          spec: "build_type=Developer +superlu-dist %clang@18"
+            spec: "build_type=Developer +superlu-dist %clang@18"
     steps:
       - uses: actions/checkout@v5
         with:

From e4678f965ca3a1715f73bf51d5b858ae8e757f26 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:04:10 +0100
Subject: [PATCH 25/90] Fixes

---
 .github/workflows/spack-matrix.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index d97e7d88..feac45c1 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -64,7 +64,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} %${{ matrix.spec }}
+          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
 
   fenics-ufcx:
     needs: style-check
@@ -140,7 +140,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} ^python@${{ matrix.python-version }}
+          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
       - name: Run tests
         if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}

From b4ef2e3898dba090a708a9c25e3cd8efff83131e Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:06:58 +0100
Subject: [PATCH 26/90] Fix python version

---
 .github/workflows/spack-matrix.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index feac45c1..529fcd5d 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -134,6 +134,7 @@ jobs:
         include:
           - version: "main"
             spec: "build_type=Developer +superlu-dist %clang@18"
+            python-version: "3.12"
     steps:
       - uses: actions/checkout@v5
         with:

From 9df431b5783cf7c3258cdcef695fb61ceceaf865 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:08:25 +0100
Subject: [PATCH 27/90] Remove more variant

---
 .github/workflows/spack-matrix.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 529fcd5d..1c80b32d 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -98,9 +98,9 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.variant }} %${{ matrix.compiler }}
+          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
-        if: ${{ matrix.version != '0.8' && contains(matrix.variant, '+ufl') }}
+        if: ${{ matrix.version != '0.8' && contains(matrix.spec, '+ufl') }}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
@@ -110,7 +110,7 @@ jobs:
           python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
-        if: ${{ matrix.version == '0.8' && contains(matrix.variant, '+ufl') }}
+        if: ${{ matrix.version == '0.8' && contains(matrix.spec, '+ufl') }}
         shell: spack-bash {0}
         run: |
           spack env activate ./env

From 5e09b6ad60ecbda49595856b71481279825b53ca Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:38:13 +0100
Subject: [PATCH 28/90] Put variant on dep.

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 1c80b32d..5a93f9bd 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -133,7 +133,7 @@ jobs:
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer +superlu-dist %clang@18"
+            spec: "build_type=Developer %clang@18 ^fenics-dolfinx+superlu-dist"
             python-version: "3.12"
     steps:
       - uses: actions/checkout@v5

From 3c2c1c1eb8039fa28c46cb7a688eab2dbf6b58d9 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:45:49 +0100
Subject: [PATCH 29/90] Bind compiler from py wrapper to C++ library

---
 spack_repo/fenics/packages/py_fenics_basix/package.py   | 8 ++++++++
 spack_repo/fenics/packages/py_fenics_dolfinx/package.py | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index cafd5b26..3be337d4 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -58,6 +58,14 @@ class PyFenicsBasix(PythonPackage):
     for ver in ("main", "0.10.0.post0", "0.10.0", "0.9.0", "0.8.0", "0.7.0", "0.6.0"):
         depends_on(f"fenics-basix@{ver}", type=("build", "run"), when=f"@{ver}")
 
+    # Ensure fenics-basix is built with same compiler.
+    depends_on("fenics-basix%gcc",   when="%gcc")
+    depends_on("fenics-basix%clang", when="%clang")
+    depends_on("fenics-basix%oneapi", when="%oneapi")
+    depends_on("fenics-basix%intel", when="%intel")
+    depends_on("fenics-basix%nvhpc", when="%nvhpc")
+    depends_on("fenics-basix%aocc",  when="%aocc")
+
     # See python/CMakeLists.txt
     depends_on("cmake@3.21:", when="@0.9:", type="build")
     depends_on("cmake@3.19:", when="@0.8", type="build")
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index 53c2eb83..69a5d84b 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -71,6 +71,14 @@ class PyFenicsDolfinx(PythonPackage):
     for ver in ["main", "0.10.0.post4", "0.9.0", "0.8.0", "0.7.2", "0.6.0"]:
         depends_on(f"fenics-dolfinx@{ver}", when=f"@{ver}")
 
+    # Ensure fenics-dolfinx is built with same compiler.
+    depends_on("fenics-dolfinx%gcc",   when="%gcc")
+    depends_on("fenics-dolfinx%clang", when="%clang")
+    depends_on("fenics-dolfinx%oneapi", when="%oneapi")
+    depends_on("fenics-dolfinx%intel", when="%intel")
+    depends_on("fenics-dolfinx%nvhpc", when="%nvhpc")
+    depends_on("fenics-dolfinx%aocc",  when="%aocc")
+
     for ver in ["main", "0.10", "0.9", "0.8", "0.7", "0.6"]:
         depends_on(f"fenics-basix@{ver}", type=("build", "link"), when=f"@{ver}")
         depends_on(f"py-fenics-basix@{ver} +ufl", type=("build", "run"), when=f"@{ver}")

From b7a97c8e544bd152d2c8880ba3094ac7f331d6d4 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 08:47:47 +0100
Subject: [PATCH 30/90] Black

---
 spack_repo/fenics/packages/py_fenics_basix/package.py   | 4 ++--
 spack_repo/fenics/packages/py_fenics_dolfinx/package.py | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index 3be337d4..261d4aef 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -59,12 +59,12 @@ class PyFenicsBasix(PythonPackage):
         depends_on(f"fenics-basix@{ver}", type=("build", "run"), when=f"@{ver}")
 
     # Ensure fenics-basix is built with same compiler.
-    depends_on("fenics-basix%gcc",   when="%gcc")
+    depends_on("fenics-basix%gcc", when="%gcc")
     depends_on("fenics-basix%clang", when="%clang")
     depends_on("fenics-basix%oneapi", when="%oneapi")
     depends_on("fenics-basix%intel", when="%intel")
     depends_on("fenics-basix%nvhpc", when="%nvhpc")
-    depends_on("fenics-basix%aocc",  when="%aocc")
+    depends_on("fenics-basix%aocc", when="%aocc")
 
     # See python/CMakeLists.txt
     depends_on("cmake@3.21:", when="@0.9:", type="build")
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index 69a5d84b..faa4d272 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -72,12 +72,12 @@ class PyFenicsDolfinx(PythonPackage):
         depends_on(f"fenics-dolfinx@{ver}", when=f"@{ver}")
 
     # Ensure fenics-dolfinx is built with same compiler.
-    depends_on("fenics-dolfinx%gcc",   when="%gcc")
+    depends_on("fenics-dolfinx%gcc", when="%gcc")
     depends_on("fenics-dolfinx%clang", when="%clang")
     depends_on("fenics-dolfinx%oneapi", when="%oneapi")
     depends_on("fenics-dolfinx%intel", when="%intel")
     depends_on("fenics-dolfinx%nvhpc", when="%nvhpc")
-    depends_on("fenics-dolfinx%aocc",  when="%aocc")
+    depends_on("fenics-dolfinx%aocc", when="%aocc")
 
     for ver in ["main", "0.10", "0.9", "0.8", "0.7", "0.6"]:
         depends_on(f"fenics-basix@{ver}", type=("build", "link"), when=f"@{ver}")

From ae7ca999dc4ab659479836a82015e93cd317e935 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 09:28:03 +0100
Subject: [PATCH 31/90] Fix

---
 .github/workflows/spack-matrix.yml                  | 13 +++++++------
 .../fenics/packages/py_fenics_basix/package.py      |  4 ++--
 .../fenics/packages/py_fenics_dolfinx/package.py    |  4 ++--
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 5a93f9bd..f1401345 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -91,7 +91,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["+ufl %gcc@13", "%clang@18"] 
+        spec: ["+ufl %gcc@13", "+ufl %clang@18"]
     steps:
       - uses: actions/checkout@v5
         with:
@@ -100,7 +100,7 @@ jobs:
         with:
           spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
-        if: ${{ matrix.version != '0.8' && contains(matrix.spec, '+ufl') }}
+        if: ${{ matrix.version != '0.8' }}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
@@ -110,7 +110,7 @@ jobs:
           python -m pytest -n auto test/
       # NOTE: 0.8 has test_all_elements_included broken
       - name: Run tests
-        if: ${{ matrix.version == '0.8' && contains(matrix.spec, '+ufl') }}
+        if: ${{ matrix.version == '0.8' }}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
@@ -128,12 +128,13 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
-        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %clang@18"]
+        # NOTE: %% propagates to dependencies - without this, C++ ABI seems to be an issue for clang.
+        spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+               "build_type=Developer %%clang@18"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %clang@18 ^fenics-dolfinx+superlu-dist"
+            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist"
             python-version: "3.12"
     steps:
       - uses: actions/checkout@v5
diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index 261d4aef..3be337d4 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -59,12 +59,12 @@ class PyFenicsBasix(PythonPackage):
         depends_on(f"fenics-basix@{ver}", type=("build", "run"), when=f"@{ver}")
 
     # Ensure fenics-basix is built with same compiler.
-    depends_on("fenics-basix%gcc", when="%gcc")
+    depends_on("fenics-basix%gcc",   when="%gcc")
     depends_on("fenics-basix%clang", when="%clang")
     depends_on("fenics-basix%oneapi", when="%oneapi")
     depends_on("fenics-basix%intel", when="%intel")
     depends_on("fenics-basix%nvhpc", when="%nvhpc")
-    depends_on("fenics-basix%aocc", when="%aocc")
+    depends_on("fenics-basix%aocc",  when="%aocc")
 
     # See python/CMakeLists.txt
     depends_on("cmake@3.21:", when="@0.9:", type="build")
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index faa4d272..69a5d84b 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -72,12 +72,12 @@ class PyFenicsDolfinx(PythonPackage):
         depends_on(f"fenics-dolfinx@{ver}", when=f"@{ver}")
 
     # Ensure fenics-dolfinx is built with same compiler.
-    depends_on("fenics-dolfinx%gcc", when="%gcc")
+    depends_on("fenics-dolfinx%gcc",   when="%gcc")
     depends_on("fenics-dolfinx%clang", when="%clang")
     depends_on("fenics-dolfinx%oneapi", when="%oneapi")
     depends_on("fenics-dolfinx%intel", when="%intel")
     depends_on("fenics-dolfinx%nvhpc", when="%nvhpc")
-    depends_on("fenics-dolfinx%aocc", when="%aocc")
+    depends_on("fenics-dolfinx%aocc",  when="%aocc")
 
     for ver in ["main", "0.10", "0.9", "0.8", "0.7", "0.6"]:
         depends_on(f"fenics-basix@{ver}", type=("build", "link"), when=f"@{ver}")

From b9f9947dcaa4208b084108f99f88df4e54b75275 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 09:32:00 +0100
Subject: [PATCH 32/90] Black fixes

---
 spack_repo/fenics/packages/py_fenics_basix/package.py   | 8 --------
 spack_repo/fenics/packages/py_fenics_dolfinx/package.py | 8 --------
 2 files changed, 16 deletions(-)

diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index 3be337d4..cafd5b26 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -58,14 +58,6 @@ class PyFenicsBasix(PythonPackage):
     for ver in ("main", "0.10.0.post0", "0.10.0", "0.9.0", "0.8.0", "0.7.0", "0.6.0"):
         depends_on(f"fenics-basix@{ver}", type=("build", "run"), when=f"@{ver}")
 
-    # Ensure fenics-basix is built with same compiler.
-    depends_on("fenics-basix%gcc",   when="%gcc")
-    depends_on("fenics-basix%clang", when="%clang")
-    depends_on("fenics-basix%oneapi", when="%oneapi")
-    depends_on("fenics-basix%intel", when="%intel")
-    depends_on("fenics-basix%nvhpc", when="%nvhpc")
-    depends_on("fenics-basix%aocc",  when="%aocc")
-
     # See python/CMakeLists.txt
     depends_on("cmake@3.21:", when="@0.9:", type="build")
     depends_on("cmake@3.19:", when="@0.8", type="build")
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index 69a5d84b..53c2eb83 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -71,14 +71,6 @@ class PyFenicsDolfinx(PythonPackage):
     for ver in ["main", "0.10.0.post4", "0.9.0", "0.8.0", "0.7.2", "0.6.0"]:
         depends_on(f"fenics-dolfinx@{ver}", when=f"@{ver}")
 
-    # Ensure fenics-dolfinx is built with same compiler.
-    depends_on("fenics-dolfinx%gcc",   when="%gcc")
-    depends_on("fenics-dolfinx%clang", when="%clang")
-    depends_on("fenics-dolfinx%oneapi", when="%oneapi")
-    depends_on("fenics-dolfinx%intel", when="%intel")
-    depends_on("fenics-dolfinx%nvhpc", when="%nvhpc")
-    depends_on("fenics-dolfinx%aocc",  when="%aocc")
-
     for ver in ["main", "0.10", "0.9", "0.8", "0.7", "0.6"]:
         depends_on(f"fenics-basix@{ver}", type=("build", "link"), when=f"@{ver}")
         depends_on(f"py-fenics-basix@{ver} +ufl", type=("build", "run"), when=f"@{ver}")

From 2dd4f2bc818f3bf5be764443f94bc23860951e31 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 10:45:19 +0100
Subject: [PATCH 33/90] Try specifying a proper MPI

---
 .github/workflows/spack-matrix.yml | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index f1401345..90044f38 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -13,6 +13,7 @@ jobs:
   style-check:
     name: ✨
     runs-on: ubuntu-latest
+
     steps:
       - uses: actions/setup-python@v6
         with:
@@ -41,6 +42,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -57,7 +59,13 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18"]
+        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18 ^mpich"]
+    env:
+      OMPI_ALLOW_RUN_AS_ROOT: 1
+      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -65,6 +73,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+      # TODO: Add C++ unit tests
 
   fenics-ufcx:
     needs: style-check
@@ -75,6 +84,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         spec: ["%gcc@13"]
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -92,6 +102,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         spec: ["+ufl %gcc@13", "+ufl %clang@18"]
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -128,14 +139,21 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
+        # NOTE: As of 2/2026 %%clang@18 seems to create dependency on mpilander stub mpi, not mpich.
         # NOTE: %% propagates to dependencies - without this, C++ ABI seems to be an issue for clang.
         spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %%clang@18"]
+               "build_type=Developer %%clang@18 ^openmpi"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist"
+            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
             python-version: "3.12"
+    env:
+      OMPI_ALLOW_RUN_AS_ROOT: 1
+      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -173,6 +191,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
+
     steps:
       - uses: actions/checkout@v5
         with:
@@ -199,6 +218,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "2025.2", "2025.1", "2024.2", "2024.1"]
+
     steps:
       - uses: actions/checkout@v5
         with:

From 81ce9f473b1e6baf0da510553347605fb669f3ec Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 11:22:49 +0100
Subject: [PATCH 34/90] Try and use unify to get C++ to propagate down leafs.

---
 .github/actions/test-package/action.yml |  5 ++++-
 .github/workflows/spack-matrix.yml      | 18 +++++++-----------
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index b9ec8234..caee863c 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -61,7 +61,10 @@ runs:
 
     - name: Concretize
       shell: spack-bash {0}
-      run: spack -e ./env concretize -j 4
+      run: |
+        spack -e ./env config add concretizer:reuse:false
+        spack -e ./env config add concretizer:unify:true
+        spack -e ./env concretize -j 4
 
     - name: Install
       shell: spack-bash {0}
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 90044f38..135d06dd 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -63,8 +63,7 @@ jobs:
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
-      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe
 
     steps:
       - uses: actions/checkout@v5
@@ -101,7 +100,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["+ufl %gcc@13", "+ufl %clang@18"]
+        spec: ["build_type=Developer +ufl %gcc@13", "build_type=Developer +ufl %clang@18"]
 
     steps:
       - uses: actions/checkout@v5
@@ -139,20 +138,17 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
-        # NOTE: As of 2/2026 %%clang@18 seems to create dependency on mpilander stub mpi, not mpich.
-        # NOTE: %% propagates to dependencies - without this, C++ ABI seems to be an issue for clang.
-        spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %%clang@18 ^openmpi"]
+        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+               "build_type=Developer %clang@18 ^openmpi"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
+            spec: "build_type=Developer %clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
             python-version: "3.12"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
-      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe
 
     steps:
       - uses: actions/checkout@v5
@@ -181,7 +177,7 @@ jobs:
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
-          mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
+          mpiexec -n 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 
   py-fenics-ffcx:
     needs: style-check

From ed5711fece4c617e11c2dfaf8732ed7abc90709b Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 11:27:10 +0100
Subject: [PATCH 35/90] Back out, didn't work.

---
 .github/actions/test-package/action.yml |  1 -
 .github/workflows/spack-matrix.yml      | 18 +++++++++++-------
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index caee863c..3aa34be6 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -62,7 +62,6 @@ runs:
     - name: Concretize
       shell: spack-bash {0}
       run: |
-        spack -e ./env config add concretizer:reuse:false
         spack -e ./env config add concretizer:unify:true
         spack -e ./env concretize -j 4
 
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 135d06dd..90044f38 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -63,7 +63,8 @@ jobs:
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
 
     steps:
       - uses: actions/checkout@v5
@@ -100,7 +101,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer +ufl %gcc@13", "build_type=Developer +ufl %clang@18"]
+        spec: ["+ufl %gcc@13", "+ufl %clang@18"]
 
     steps:
       - uses: actions/checkout@v5
@@ -138,17 +139,20 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
-        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %clang@18 ^openmpi"]
+        # NOTE: As of 2/2026 %%clang@18 seems to create dependency on mpilander stub mpi, not mpich.
+        # NOTE: %% propagates to dependencies - without this, C++ ABI seems to be an issue for clang.
+        spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+               "build_type=Developer %%clang@18 ^openmpi"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
+            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
             python-version: "3.12"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
 
     steps:
       - uses: actions/checkout@v5
@@ -177,7 +181,7 @@ jobs:
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
-          mpiexec -n 3 python -m pytest -k "not test_cffi_expression" python/test/unit
+          mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
 
   py-fenics-ffcx:
     needs: style-check

From c820020ee8e4f784e2fe29d5d6f82d2361ea3564 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 11:43:25 +0100
Subject: [PATCH 36/90] Fixes, should pass (eep)

---
 .github/workflows/spack-matrix.yml | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 90044f38..e9e00dc0 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -101,7 +101,8 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["+ufl %gcc@13", "+ufl %clang@18"]
+        # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
+        spec: ["+ufl %gcc@13 ^fenics-basix %gcc@13", "+ufl %clang@18 ^fenics-basix %clang@18"]
 
     steps:
       - uses: actions/checkout@v5
@@ -140,7 +141,8 @@ jobs:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
         # NOTE: As of 2/2026 %%clang@18 seems to create dependency on mpilander stub mpi, not mpich.
-        # NOTE: %% propagates to dependencies - without this, C++ ABI seems to be an issue for clang.
+        # NOTE: %% propagates to dependencies - without this, C++ ABI mixing
+        # seems to be an issue through Basix/DOLFINx.
         spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
                "build_type=Developer %%clang@18 ^openmpi"]
         # Test new superlu-dist variant
@@ -171,7 +173,7 @@ jobs:
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-          mpiexec -n 3 python -m pytest -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
         shell: spack-bash {0}
@@ -180,8 +182,8 @@ jobs:
           spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -k "not test_cffi_expression" python/test/unit
-          mpiexec -np 3 python -m pytest -k "not test_cffi_expression" python/test/unit
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
+          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
 
   py-fenics-ffcx:
     needs: style-check

From f68cfd79e18061c985c1a129d788ac35067f1866 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 13:30:31 +0100
Subject: [PATCH 37/90] Try tests + try tighter spec of %clang@18

---
 .github/workflows/spack-matrix.yml | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index e9e00dc0..d28f187f 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -59,7 +59,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18 ^mpich"]
+        spec: ["build_type=Developer %gcc@13 catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18 ^mpich catch2"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -73,7 +73,18 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
-      # TODO: Add C++ unit tests
+      - name: Run tests
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+          spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+          cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
+          cmake --build build/test
+          cd build/test
+          ctest -V --output-on-failure -R unittests_np_1
+          ctest -V --output-on-failure -R unittests_np_3
+
 
   fenics-ufcx:
     needs: style-check
@@ -102,7 +113,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
-        spec: ["+ufl %gcc@13 ^fenics-basix %gcc@13", "+ufl %clang@18 ^fenics-basix %clang@18"]
+        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %clang@18 ^fenics-basix%clang@18"]
 
     steps:
       - uses: actions/checkout@v5
@@ -140,15 +151,14 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         python-version: ["3.10", "3.13"]
-        # NOTE: As of 2/2026 %%clang@18 seems to create dependency on mpilander stub mpi, not mpich.
-        # NOTE: %% propagates to dependencies - without this, C++ ABI mixing
-        # seems to be an issue through Basix/DOLFINx.
-        spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %%clang@18 ^openmpi"]
+        # NOTE: As of 2/2026 %clang@18 seems to create dependency on mpilander stub mpi or intelmpi.
+        # NOTE: Some overspecification of %clang@18 to fix ABI issues (std::string).
+        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+               "build_type=Developer %clang@18 ^openmpi ^fenics-dolfinx%clang@18 ^py-fenics-dolfinx%clang@18 ^fenics-basix%clang@18"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %%clang@18 ^fenics-dolfinx+superlu-dist ^mpich"
+            spec: "build_type=Developer %clang@18 ^mpich ^fenics-dolfinx+superlu-dist%clang@18 ^py-fenics-dolfinx%clang@18 ^fenics-basix%clang@18"
             python-version: "3.12"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
@@ -172,7 +182,7 @@ jobs:
           spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
           spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
           mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
       - name: Run tests
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}

From 5ca5d617ff5ba9a324b2d71d9f1f6a7f5f6c6380 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 13:45:26 +0100
Subject: [PATCH 38/90] Fix.

---
 .github/workflows/spack-matrix.yml | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index d28f187f..ea05d8f7 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -59,7 +59,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %gcc@13 catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %clang@18 ^mpich catch2"]
+        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%clang@18 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -77,6 +77,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
+          spack install --add catch2
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
@@ -113,7 +114,7 @@ jobs:
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
         # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
-        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %clang@18 ^fenics-basix%clang@18"]
+        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %%clang@18 ^fenics-basix%clang@18"]
 
     steps:
       - uses: actions/checkout@v5
@@ -154,11 +155,11 @@ jobs:
         # NOTE: As of 2/2026 %clang@18 seems to create dependency on mpilander stub mpi or intelmpi.
         # NOTE: Some overspecification of %clang@18 to fix ABI issues (std::string).
         spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %clang@18 ^openmpi ^fenics-dolfinx%clang@18 ^py-fenics-dolfinx%clang@18 ^fenics-basix%clang@18"]
+               "build_type=Developer %%clang@18 ^openmpi"]
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %clang@18 ^mpich ^fenics-dolfinx+superlu-dist%clang@18 ^py-fenics-dolfinx%clang@18 ^fenics-basix%clang@18"
+            spec: "build_type=Developer %%clang@18 ^mpich ^fenics-dolfinx+superlu-dist"
             python-version: "3.12"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1

From 01168bf6d257f738c1798a9faacff06262524ed7 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 13:55:15 +0100
Subject: [PATCH 39/90] Load cmake

---
 .github/workflows/spack-matrix.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index ea05d8f7..3e7ee159 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -77,8 +77,9 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add catch2
-          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+          spack install --add catch2 cmake
+          spack load catch2 cmake
+          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
           cmake --build build/test

From 6ea98f17c32396ee26ddfeea5ae14441c5b50d46 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 13:55:33 +0100
Subject: [PATCH 40/90] Try with just cmake

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 3e7ee159..67bb801f 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add catch2 cmake
-          spack load catch2 cmake
+          spack load cmake
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer

From 599e16e6e57c8e67360445f4aacb46c2ba9852aa Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 14:08:01 +0100
Subject: [PATCH 41/90] Fix.

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 67bb801f..89ec620a 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -77,7 +77,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add catch2 cmake
+          spack install --add catch2 cmake %gcc@13
           spack load cmake
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}

From 75000d688b4b357f5626b35f68ef566eadc2d46a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 14:29:09 +0100
Subject: [PATCH 42/90] Fix cmake version to load

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 89ec620a..78b7449e 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add catch2 cmake %gcc@13
-          spack load cmake
+          spack load cmake@31.31.11
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer

From 7d2356460c4c34b28df6480384c20515fce3b701 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 14:49:01 +0100
Subject: [PATCH 43/90] Try this

---
 .github/workflows/spack-matrix.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 78b7449e..67bb801f 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -77,8 +77,8 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add catch2 cmake %gcc@13
-          spack load cmake@31.31.11
+          spack install --add catch2 cmake
+          spack load cmake
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer

From 4c687ac2635c4232fa18c127b3eef2f3023d7399 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 15:03:09 +0100
Subject: [PATCH 44/90] Don't allow duplicates (might be too strong)

---
 .github/actions/test-package/action.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 3aa34be6..e36e3d14 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -63,6 +63,7 @@ runs:
       shell: spack-bash {0}
       run: |
         spack -e ./env config add concretizer:unify:true
+        spack -e ./env config add concretizer:duplicates:strategy:none
         spack -e ./env concretize -j 4
 
     - name: Install

From 4f43b51f793cacb4e4b3e66eecff4097c7a3b8ef Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 15:09:28 +0100
Subject: [PATCH 45/90] Fix.

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 67bb801f..f42af5ad 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -59,7 +59,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %gcc@13", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%clang@18 ^mpich"]
+        spec: ["build_type=Developer %%clang@18", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From 49c9ba9a4d968e7d7a51cef5135c8215afa83701 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Tue, 10 Feb 2026 17:42:11 +0100
Subject: [PATCH 46/90] Load first cmake

---
 .github/actions/test-package/action.yml | 1 -
 .github/workflows/spack-matrix.yml      | 4 ++--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index e36e3d14..3aa34be6 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -63,7 +63,6 @@ runs:
       shell: spack-bash {0}
       run: |
         spack -e ./env config add concretizer:unify:true
-        spack -e ./env config add concretizer:duplicates:strategy:none
         spack -e ./env concretize -j 4
 
     - name: Install
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index f42af5ad..2dc883a3 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
         run: |
           spack env activate ./env
           spack install --add catch2 cmake
-          spack load cmake
+          spack load --first cmake
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
@@ -160,7 +160,7 @@ jobs:
         # Test new superlu-dist variant
         include:
           - version: "main"
-            spec: "build_type=Developer %%clang@18 ^mpich ^fenics-dolfinx+superlu-dist"
+            spec: "build_type=Developer %%clang@18 ^mpich-fortran ^fenics-dolfinx+superlu-dist"
             python-version: "3.12"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1

From bf9f2670d427b67abf9012d783b20c2bfd6cf427 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Wed, 11 Feb 2026 22:01:58 +0100
Subject: [PATCH 47/90] Add Spacks pyproject

---
 pyproject.toml | 531 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 531 insertions(+)
 create mode 100644 pyproject.toml

diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 00000000..c081cdb8
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,531 @@
+[project]
+name = "spack"
+description = "The spack package manager"
+requires-python = ">=3.6"
+dependencies = ["clingo", "setuptools"]
+dynamic = ["version"]
+
+[tool.hatch.version]
+path = "repos/spack_repo/builtin/__init__.py"
+
+[project.optional-dependencies]
+dev = [
+  "pip>=21.3",
+  "pytest",
+  "pytest-xdist",
+  "setuptools",
+  "click",
+  "black",
+  "mypy",
+  "isort",
+  "flake8",
+  "vermin",
+]
+ci = ["pytest-cov", "codecov[toml]"]
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+include = [
+  "/repos",
+  "CITATION.cff",
+  "COPYRIGHT",
+  "LICENSE-APACHE",
+  "LICENSE-MIT",
+  "NOTICE",
+  "README.md",
+  "SECURITY.md",
+]
+
+[tool.hatch.envs.default]
+features = ["dev"]
+
+[tool.hatch.envs.ci]
+features = ["dev", "ci"]
+
+[tool.ruff]
+line-length = 99
+extend-include = ["bin/spack"]
+extend-exclude = ["lib/spack/external", "*.pyi"]
+
+# This is the Spack package API. We allow these functions to be imported with
+# from spack.package import *, and we should update this when the package API
+# changes. This also serves to catch the usage of things that are NOT in the
+# package API, so that we can avoid having them in builtin.
+builtins = [
+    # core spack build environment
+    "configure",
+    "cscript",
+    "dso_suffix",
+    "make_jobs",
+    "msbuild",
+    "nmake",
+    "prefix",
+    "python",
+    "python_include",
+    "python_platlib",
+    "python_purelib",
+    "spack_cc",
+    "spack_cxx",
+    "spack_f77",
+    "spack_fc",
+    "static_to_shared_library",
+    # defined in packages or build systems, e.g. -- these can be removed over time
+    "aclocal",
+    "autoconf",
+    "autoheader",
+    "autom4te",
+    "automake",
+    "autoreconf",
+    "autoscan",
+    "autoupdate",
+    "bazel",
+    "cargo",
+    "cmake",
+    "ctest",
+    "gem",
+    "glibtool",
+    "glibtoolize",
+    "gmake",
+    "go",
+    "ifnames",
+    "kentutils_htslib_include_dir",
+    "kentutils_include_dir",
+    "kentutils_lib_dir",
+    "libtool",
+    "libtoolize",
+    "lua",
+    "luarocks",
+    "make",
+    "make",
+    "meson",
+    "msbuild",
+    "ninja",
+    "ninja",
+    "nmake",
+    "octave",
+    "perl",
+    "perl_lib_dir",
+    "pip",
+    "plumed",
+    "pypy",
+    "python",
+    "python_include",
+    "python_platlib",
+    "python_purelib",
+    "qmake",
+    "R",
+    "r_lib_dir",
+    "rake",
+    "ruby",
+    "scons",
+    # v2.0
+    "BaseBuilder",
+    "Builder",
+    "Dict",
+    "EnvironmentModifications",
+    "Executable",
+    "FileFilter",
+    "FileList",
+    "HeaderList",
+    "InstallError",
+    "LibraryList",
+    "List",
+    "MakeExecutable",
+    "NoHeadersError",
+    "NoLibrariesError",
+    "Optional",
+    "PackageBase",
+    "Prefix",
+    "ProcessError",
+    "SkipTest",
+    "Spec",
+    "Version",
+    "all_deptypes",
+    "ancestor",
+    "any_combination_of",
+    "auto_or_any_combination_of",
+    "bash_completion_path",
+    "build_system_flags",
+    "build_system",
+    "cache_extra_test_sources",
+    "can_access",
+    "can_splice",
+    "cd",
+    "change_sed_delimiter",
+    "check_outputs",
+    "conditional",
+    "conflicts",
+    "copy_tree",
+    "copy",
+    "default_args",
+    "depends_on",
+    "determine_number_of_jobs",
+    "disjoint_sets",
+    "env_flags",
+    "env",
+    "extends",
+    "filter_compiler_wrappers",
+    "filter_file",
+    "find_all_headers",
+    "find_first",
+    "find_headers",
+    "find_libraries",
+    "find_required_file",
+    "find_system_libraries",
+    "find",
+    "fish_completion_path",
+    "fix_darwin_install_name",
+    "force_remove",
+    "force_symlink",
+    "get_escaped_text_output",
+    "inject_flags",
+    "install_test_root",
+    "install_tree",
+    "install",
+    "is_exe",
+    "join_path",
+    "keep_modification_time",
+    "library_extensions",
+    "license",
+    "maintainers",
+    "makedirs",
+    "mkdir",
+    "mkdirp",
+    "move",
+    "on_package_attributes",
+    "patch",
+    "provides",
+    "pwd",
+    "redistribute",
+    "register_builder",
+    "remove_directory_contents",
+    "remove_linked_tree",
+    "remove",
+    "removedirs",
+    "rename",
+    "requires",
+    "resource",
+    "rmtree",
+    "run_after",
+    "run_before",
+    "set_executable",
+    "set_install_permissions",
+    "symlink",
+    "test_part",
+    "touch",
+    "tty",
+    "variant",
+    "ver",
+    "version",
+    "when",
+    "which_string",
+    "which",
+    "working_dir",
+    "zsh_completion_path",
+    # v2.1
+    "CompilerError",
+    "SpackError",
+    # v2.2
+    "BuilderWithDefaults",
+    "ClassProperty",
+    "CompilerPropertyDetector",
+    "GenericBuilder",
+    "HKEY",
+    "LC_ID_DYLIB",
+    "LinkTree",
+    "MachO",
+    "ModuleChangePropagator",
+    "Package",
+    "WindowsRegistryView",
+    "apply_macos_rpath_fixups",
+    "classproperty",
+    "compare_output_file",
+    "compare_output",
+    "compile_c_and_execute",
+    "compiler_spec",
+    "create_builder",
+    "dedupe",
+    "delete_needed_from_elf",
+    "delete_rpath",
+    "environment_modifications_for_specs",
+    "execute_install_time_tests",
+    "filter_shebang",
+    "filter_system_paths",
+    "find_all_libraries",
+    "find_compilers",
+    "get_cmake_prefix_path",
+    "get_effective_jobs",
+    "get_elf_compat",
+    "get_path_args_from_module_line",
+    "get_user",
+    "has_shebang",
+    "host_platform",
+    "is_system_path",
+    "join_url",
+    "kernel_version",
+    "libc_from_dynamic_linker",
+    "macos_version",
+    "make_package_test_rpath",
+    "memoized",
+    "microarchitecture_flags_from_target",
+    "microarchitecture_flags",
+    "module_command",
+    "parse_dynamic_linker",
+    "parse_elf",
+    "path_contains_subdirectory",
+    "readlink",
+    "safe_remove",
+    "sbang_install_path",
+    "sbang_shebang_line",
+    "set_env",
+    "shared_library_suffix",
+    "spack_script",
+    "static_library_suffix",
+    "substitute_version_in_url",
+    "windows_sfn",
+]
+
+
+[tool.ruff.format]
+skip-magic-trailing-comma = false
+
+[tool.ruff.lint]
+extend-select = ["I"]
+ignore = ["E731", "E203", "F403", "F811"]
+
+[tool.ruff.lint.isort]
+split-on-trailing-comma = false
+section-order = [
+  "future",
+  "standard-library",
+  "third-party",
+  "llnl",
+  "spack",
+  "first-party",
+  "local-folder",
+]
+
+[tool.ruff.lint.isort.sections]
+spack = ["spack"]
+llnl = ["llnl"]
+
+[tool.ruff.lint.per-file-ignores]
+"var/spack/*/package.py" = ["F403", "F405", "F811", "F821"]
+"*-ci-package.py" = ["F403", "F405", "F821"]
+
+[tool.black]
+line-length = 99
+include = "(repos/spack_repo|tests)/.*\\.pyi?$"
+skip_magic_trailing_comma = true
+
+[tool.isort]
+line_length = 99
+profile = "black"
+sections = [
+  "FUTURE",
+  "STDLIB",
+  "THIRDPARTY",
+  "LLNL",
+  "FIRSTPARTY",
+  "LOCALFOLDER",
+]
+known_first_party = "spack"
+known_llnl = "llnl"
+known_third_party = ["ruamel", "six"]
+src_paths = "lib"
+honor_noqa = true
+
+[tool.mypy]
+files = [
+  "repos/spack_repo/builtin/packages/*/package.py",
+  "repos/spack_repo/builtin/build_systems/*.py",
+]
+mypy_path = ["spack-core/lib/spack", "spack-core/lib/spack/external", "repos/"]
+allow_redefinition = true
+
+# This and a generated import file allows supporting packages
+namespace_packages = true
+
+# To avoid re-factoring all the externals, ignore errors and missing imports
+# globally, then turn back on in spack and spack submodules
+ignore_errors = true
+ignore_missing_imports = true
+
+[[tool.mypy.overrides]]
+module = "spack.*"
+ignore_errors = false
+ignore_missing_imports = false
+
+[[tool.mypy.overrides]]
+module = "spack_repo.*"
+ignore_errors = false
+ignore_missing_imports = false
+# we can't do this here, not a module scope option, in spack style instead
+# disable_error_code = 'no-redef'
+
+[[tool.mypy.overrides]]
+module = "llnl.*"
+ignore_errors = false
+ignore_missing_imports = false
+
+[[tool.mypy.overrides]]
+module = "spack.test.packages"
+ignore_errors = true
+
+# ignore errors in fake import path for packages
+[[tool.mypy.overrides]]
+module = "spack.pkg.*"
+ignore_errors = true
+ignore_missing_imports = true
+
+# Spack imports a number of external packages, and they *may* require Python 3.8 or
+# higher in recent versions. This can cause mypy to fail because we check for 3.7
+# compatibility. We could restrict mypy to run for the oldest supported version (3.7),
+# but that means most developers won't be able to run mypy, which means it'll fail
+# more in CI. Instead, we exclude these imported packages from mypy checking.
+[[tool.mypy.overrides]]
+module = [
+  "IPython",
+  "altgraph",
+  "attr",
+  "boto3",
+  "botocore",
+  "distro",
+  "importlib.metadata",
+  "jinja2",
+  "jsonschema",
+  "macholib",
+  "markupsafe",
+  "numpy",
+  "pkg_resources",
+  "pyristent",
+  "pytest",
+  "ruamel.yaml",
+  "six",
+]
+follow_imports = "skip"
+follow_imports_for_stubs = true
+
+[tool.pyright]
+useLibraryCodeForTypes = true
+reportMissingImports = true
+reportWildcardImportFromLibrary = false
+include = ["lib/spack", "var/spack/repos", "var/spack/test_repos"]
+ignore = ["lib/spack/external"]
+extraPaths = ["lib/spack", "lib/spack/external"]
+
+
+[tool.coverage.run]
+parallel = true
+concurrency = ["multiprocessing"]
+branch = true
+source = ["bin", "lib"]
+data_file = "./tests-coverage/.coverage"
+omit = [
+  "lib/spack/spack/test/*",
+  "lib/spack/docs/*",
+  "lib/spack/external/*",
+  "share/spack/qa/*",
+]
+
+[tool.coverage.report]
+# Regexes for lines to exclude from consideration
+exclude_lines = [
+  # Have to re-enable the standard pragma
+  "pragma: no cover",
+
+  # Don't complain about missing debug-only code:
+  "def __repr__",
+  "if self\\.debug",
+
+  # Don't complain if tests don't hit defensive assertion code:
+  "raise AssertionError",
+  "raise NotImplementedError",
+
+  # Don't complain if non-runnable code isn't run:
+  "if 0:",
+  "if False:",
+  "if __name__ == .__main__.:",
+]
+ignore_errors = true
+
+[tool.coverage.paths]
+source = [
+  ".",
+  "/Users/runner/work/spack/spack",
+  "/System/Volumes/Data/home/runner/work/spack/spack",
+  "D:\\a\\spack\\spack",
+]
+
+[tool.coverage.html]
+directory = "htmlcov"
+
+[tool.vendoring]
+destination = "lib/spack/external/_vendoring"
+requirements = "lib/spack/external/vendor.txt"
+namespace = ""
+
+protected-files = ["__init__.py", "README.rst", "vendor.txt"]
+patches-dir = "lib/spack/external/patches"
+
+[tool.vendoring.transformations]
+substitute = [
+  { match = "typing_extensions", replace = "_vendoring.typing_extensions" },
+  { match = "ruamel.yaml", replace = "_vendoring.ruamel.yaml" },
+  { match = "altgraph", replace = "_vendoring.altgraph" },
+  { match = "macholib", replace = "_vendoring.macholib" },
+  { match = "from six", replace = "from _vendoring.six" },
+  { match = "markupsafe", replace = "_vendoring.markupsafe" },
+  { match = "jinja2", replace = "_vendoring.jinja2" },
+  { match = "pyrsistent", replace = "_vendoring.pyrsistent" },
+  { match = "import attr\n", replace = "import _vendoring.attr\n" },
+  { match = "from attr", replace = "from _vendoring.attr" },
+  { match = "import jsonschema", replace = "import _vendoring.jsonschema" },
+  { match = "from jsonschema", replace = "from _vendoring.jsonschema" },
+]
+drop = [
+  # contains unnecessary scripts
+  "bin/",
+  # interpreter and OS specific msgpack libs
+  "msgpack/*.so",
+  # unneeded parts of setuptools
+  "easy_install.py",
+  "setuptools",
+  "pkg_resources/_vendor/",
+  "pkg_resources/extern/",
+  # trim vendored pygments styles and lexers
+  "pygments/styles/[!_]*.py",
+  "^pygments/lexers/(?!python|__init__|_mapping).*\\.py$",
+  # trim rich's markdown support
+  "rich/markdown.py",
+  # ruamel.yaml installs unneded files
+  "ruamel.*.pth",
+  "pvectorc.*.so",
+  # Trim jsonschema tests
+  "jsonschema/tests",
+  "archspec/json/tests",
+  "archspec/vendor/cpuid/.gitignore",
+  "pyrsistent/__init__.pyi",
+]
+
+[tool.vendoring.typing-stubs]
+_pyrsistent_version = []
+altgraph = []
+archspec = []
+distro = []
+jsonschema = []
+macholib = []
+pyrsistent = []
+ruamel = []
+six = []
+
+[tool.vendoring.license.directories]
+setuptools = "pkg_resources"
+
+[tool.vendoring.license.fallback-urls]
+CacheControl = "https://raw.githubusercontent.com/ionrock/cachecontrol/v0.12.6/LICENSE.txt"
+distlib = "https://bitbucket.org/pypa/distlib/raw/master/LICENSE.txt"
+webencodings = "https://github.com/SimonSapin/python-webencodings/raw/master/LICENSE"

From 07d567f5253921f2f9594c357d0c6d7912863104 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Wed, 11 Feb 2026 22:03:29 +0100
Subject: [PATCH 48/90] black

---
 .../fenics/packages/fenics_basix/package.py   |  4 ++-
 .../fenics/packages/fenics_dolfinx/package.py | 34 +++++--------------
 .../fenics/packages/fenics_ufcx/package.py    | 25 +++-----------
 .../packages/py_fenics_basix/package.py       | 28 ++++-----------
 .../packages/py_fenics_dolfinx/package.py     | 29 ++++------------
 .../fenics/packages/py_fenics_ffcx/package.py |  4 ++-
 6 files changed, 31 insertions(+), 93 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_basix/package.py b/spack_repo/fenics/packages/fenics_basix/package.py
index 8581f6e1..a85afc31 100644
--- a/spack_repo/fenics/packages/fenics_basix/package.py
+++ b/spack_repo/fenics/packages/fenics_basix/package.py
@@ -18,7 +18,9 @@ class FenicsBasix(CMakePackage):
     license("MIT")
 
     version("main", branch="main", no_cache=True)
-    version("0.10.0.post0", sha256="11a6482fb8d7204fbd77aaf457a9ae3e75db1707b3e30ea2c938eccfee925ea4")
+    version(
+        "0.10.0.post0", sha256="11a6482fb8d7204fbd77aaf457a9ae3e75db1707b3e30ea2c938eccfee925ea4"
+    )
     version("0.10.0", sha256="b93221dac7d3fea8c10e77617f6201036de35d0c5437440b718de69a28c3773f")
     version("0.9.0", sha256="60e96b2393084729b261cb10370f0e44d12735ab3dbd1f15890dec23b9e85329")
     version("0.8.0", sha256="b299af82daf8fa3e4845e17f202491fe71b313bf6ab64c767a5287190b3dd7fe")
diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 5b707521..61462c1b 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -17,30 +17,16 @@ class FenicsDolfinx(CMakePackage):
 
     version("main", branch="main", no_cache=True)
     version(
-        "0.10.0.post4",
-        sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605",
+        "0.10.0.post4", sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605"
     )
     version(
-        "0.10.0.post2",
-        sha256="eae83794fee8141c80c59c03a2f4ac208af2b62c8f36e5d19c93e0d279029f52",
-    )
-    version(
-        "0.9.0",
-        sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1",
-    )
-    version(
-        "0.8.0",
-        sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9",
+        "0.10.0.post2", sha256="eae83794fee8141c80c59c03a2f4ac208af2b62c8f36e5d19c93e0d279029f52"
     )
+    version("0.9.0", sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1")
+    version("0.8.0", sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9")
     with default_args(deprecated=True):
-        version(
-            "0.7.2",
-            sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b",
-        )
-        version(
-            "0.6.0",
-            sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80",
-        )
+        version("0.7.2", sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b")
+        version("0.6.0", sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80")
 
     patch("0.8-boost-filesystem.patch", when="@0.8")
 
@@ -74,9 +60,7 @@ class FenicsDolfinx(CMakePackage):
     variant("slepc", default=False, description="SLEPc support")
     variant("adios2", default=False, description="ADIOS2 support")
     variant("petsc", default=False, description="PETSc support")
-    variant(
-        "superlu-dist", default=False, description="SuperLU_DIST support", when="@main"
-    )
+    variant("superlu-dist", default=False, description="SuperLU_DIST support", when="@main")
 
     conflicts("~petsc", when="+slepc", msg="+slepc requires +petsc")
 
@@ -118,9 +102,7 @@ def cmake_args(self):
             self.define_from_variant("DOLFINX_ENABLE_ADIOS2", "adios2"),
             self.define("DOLFINX_UFCX_PYTHON", False),
             self.define("DOLFINX_ENABLE_KAHIP", "partitioners=kahip" in self.spec),
-            self.define(
-                "DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec
-            ),
+            self.define("DOLFINX_ENABLE_PARMETIS", "partitioners=parmetis" in self.spec),
             self.define("DOLFINX_ENABLE_SCOTCH", "partitioners=scotch" in self.spec),
             self.define("DOLFINX_ENABLE_SUPERLU_DIST", "superlu-dist" in self.spec),
         ]
diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index 5127071f..db187cff 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -19,27 +19,12 @@ class FenicsUfcx(CMakePackage):
     license("Unlicense")
 
     version("main", branch="main", no_cache=True)
-    version(
-        "0.10.0",
-        sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9",
-    )
-    version(
-        "0.9.0",
-        sha256="afa517272a3d2249f513cb711c50b77cf8368dd0b8f5ea4b759142229204a448",
-    )
-    version(
-        "0.8.0",
-        sha256="8a854782dbd119ec1c23c4522a2134d5281e7f1bd2f37d64489f75da055282e3",
-    )
+    version("0.10.0", sha256="fa27e2dc68988cbf9aca537eb5a58483f75cc719c1a383713b7f8cca49844ff9")
+    version("0.9.0", sha256="afa517272a3d2249f513cb711c50b77cf8368dd0b8f5ea4b759142229204a448")
+    version("0.8.0", sha256="8a854782dbd119ec1c23c4522a2134d5281e7f1bd2f37d64489f75da055282e3")
     with default_args(deprecated=True):
-        version(
-            "0.7.0",
-            sha256="7f3c3ca91d63ce7831d37799cc19d0551bdcd275bdfa4c099711679533dd1c71",
-        )
-        version(
-            "0.6.0",
-            sha256="076fad61d406afffd41019ae1abf6da3f76406c035c772abad2156127667980e",
-        )
+        version("0.7.0", sha256="7f3c3ca91d63ce7831d37799cc19d0551bdcd275bdfa4c099711679533dd1c71")
+        version("0.6.0", sha256="076fad61d406afffd41019ae1abf6da3f76406c035c772abad2156127667980e")
 
     depends_on("cmake@3.19:", type="build")
     depends_on("c", type="build")
diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index cafd5b26..dc20efad 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -18,30 +18,14 @@ class PyFenicsBasix(PythonPackage):
 
     version("main", branch="main", no_cache=True)
     version(
-        "0.10.0.post0",
-        sha256="11a6482fb8d7204fbd77aaf457a9ae3e75db1707b3e30ea2c938eccfee925ea4",
-    )
-    version(
-        "0.10.0",
-        sha256="b93221dac7d3fea8c10e77617f6201036de35d0c5437440b718de69a28c3773f",
-    )
-    version(
-        "0.9.0",
-        sha256="60e96b2393084729b261cb10370f0e44d12735ab3dbd1f15890dec23b9e85329",
-    )
-    version(
-        "0.8.0",
-        sha256="b299af82daf8fa3e4845e17f202491fe71b313bf6ab64c767a5287190b3dd7fe",
+        "0.10.0.post0", sha256="11a6482fb8d7204fbd77aaf457a9ae3e75db1707b3e30ea2c938eccfee925ea4"
     )
+    version("0.10.0", sha256="b93221dac7d3fea8c10e77617f6201036de35d0c5437440b718de69a28c3773f")
+    version("0.9.0", sha256="60e96b2393084729b261cb10370f0e44d12735ab3dbd1f15890dec23b9e85329")
+    version("0.8.0", sha256="b299af82daf8fa3e4845e17f202491fe71b313bf6ab64c767a5287190b3dd7fe")
     with default_args(deprecated=True):
-        version(
-            "0.7.0",
-            sha256="9bee81b396ee452eec8d9735f278cb44cb6994c6bc30aec8ed9bb4b12d83fa7f",
-        )
-        version(
-            "0.6.0",
-            sha256="687ae53153c98facac4080dcdc7081701db1dcea8c5e7ae3feb72aec17f83304",
-        )
+        version("0.7.0", sha256="9bee81b396ee452eec8d9735f278cb44cb6994c6bc30aec8ed9bb4b12d83fa7f")
+        version("0.6.0", sha256="687ae53153c98facac4080dcdc7081701db1dcea8c5e7ae3feb72aec17f83304")
 
     # CMake build type
     variant(
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index 53c2eb83..7aafdcd3 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -19,26 +19,13 @@ class PyFenicsDolfinx(PythonPackage):
 
     version("main", branch="main", no_cache=True)
     version(
-        "0.10.0.post4",
-        sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605",
-    )
-    version(
-        "0.9.0",
-        sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1",
-    )
-    version(
-        "0.8.0",
-        sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9",
+        "0.10.0.post4", sha256="3f827a88ab52843fbd7a5cc7814ecba165bdec65fd10df05eb031c286e8cd605"
     )
+    version("0.9.0", sha256="b266c74360c2590c5745d74768c04568c965b44739becca4cd6b5aa58cdbbbd1")
+    version("0.8.0", sha256="acf3104d9ecc0380677a6faf69eabfafc58d0cce43f7777e1307b95701c7cad9")
     with default_args(deprecated=True):
-        version(
-            "0.7.2",
-            sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b",
-        )
-        version(
-            "0.6.0",
-            sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80",
-        )
+        version("0.7.2", sha256="7d9ce1338ce66580593b376327f23ac464a4ce89ef63c105efc1a38e5eae5c0b")
+        version("0.6.0", sha256="eb8ac2bb2f032b0d393977993e1ab6b4101a84d54023a67206e3eac1a8d79b80")
 
     # CMake build type
     variant(
@@ -89,11 +76,7 @@ class PyFenicsDolfinx(PythonPackage):
     depends_on("py-numpy@1.21:", type=("build", "run"))
     depends_on("py-mpi4py", type=("build", "run"))
 
-    conflicts(
-        "~petsc4py",
-        when="@:0.8",
-        msg="+petsc4py is required for versions 0.8 and lower",
-    )
+    conflicts("~petsc4py", when="@:0.8", msg="+petsc4py is required for versions 0.8 and lower")
     conflicts("~petsc4py", when="+slepc4py", msg="+slepc4py requires +petsc4py")
     with when("+petsc4py"):
         depends_on("fenics-dolfinx +petsc")
diff --git a/spack_repo/fenics/packages/py_fenics_ffcx/package.py b/spack_repo/fenics/packages/py_fenics_ffcx/package.py
index 4d49f5b0..de101992 100644
--- a/spack_repo/fenics/packages/py_fenics_ffcx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_ffcx/package.py
@@ -18,7 +18,9 @@ class PyFenicsFfcx(PythonPackage):
     license("LGPL-3.0-or-later")
 
     version("main", branch="main", no_cache=True)
-    version("0.10.1.post0", sha256="91e15e2586390d0a0b0e9993d63b47b7ae9657e5141fc30271291ea1a2d55d5e")
+    version(
+        "0.10.1.post0", sha256="91e15e2586390d0a0b0e9993d63b47b7ae9657e5141fc30271291ea1a2d55d5e"
+    )
     version("0.9.0", sha256="afa517272a3d2249f513cb711c50b77cf8368dd0b8f5ea4b759142229204a448")
     version("0.8.0", sha256="8a854782dbd119ec1c23c4522a2134d5281e7f1bd2f37d64489f75da055282e3")
     with default_args(deprecated=True):

From a775f0f60b578139f122e6c0bb65e8806719c210 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Wed, 11 Feb 2026 22:03:37 +0100
Subject: [PATCH 49/90] isort

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py    | 3 ++-
 spack_repo/fenics/packages/fenics_ufcx/package.py       | 3 ++-
 spack_repo/fenics/packages/py_fenics_basix/package.py   | 3 ++-
 spack_repo/fenics/packages/py_fenics_dolfinx/package.py | 3 ++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 61462c1b..53dda50a 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -2,9 +2,10 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack.package import *
 from spack_repo.builtin.build_systems.cmake import CMakePackage
 
+from spack.package import *
+
 
 class FenicsDolfinx(CMakePackage):
     """Next generation FEniCS problem solving environment."""
diff --git a/spack_repo/fenics/packages/fenics_ufcx/package.py b/spack_repo/fenics/packages/fenics_ufcx/package.py
index db187cff..433bc49b 100644
--- a/spack_repo/fenics/packages/fenics_ufcx/package.py
+++ b/spack_repo/fenics/packages/fenics_ufcx/package.py
@@ -2,9 +2,10 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack.package import *
 from spack_repo.builtin.build_systems.cmake import CMakePackage
 
+from spack.package import *
+
 
 class FenicsUfcx(CMakePackage):
     """FFCx provides the ufcx.h interface header for generated finite element
diff --git a/spack_repo/fenics/packages/py_fenics_basix/package.py b/spack_repo/fenics/packages/py_fenics_basix/package.py
index dc20efad..df384eb5 100644
--- a/spack_repo/fenics/packages/py_fenics_basix/package.py
+++ b/spack_repo/fenics/packages/py_fenics_basix/package.py
@@ -2,9 +2,10 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack.package import *
 from spack_repo.builtin.build_systems.python import PythonPackage
 
+from spack.package import *
+
 
 class PyFenicsBasix(PythonPackage):
     """Python interface to Basix, a finite element definition and tabulation runtime library"""
diff --git a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
index 7aafdcd3..50a11956 100644
--- a/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/py_fenics_dolfinx/package.py
@@ -2,9 +2,10 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-from spack.package import *
 from spack_repo.builtin.build_systems.python import PythonPackage
 
+from spack.package import *
+
 
 class PyFenicsDolfinx(PythonPackage):
     """Python interface to the next generation FEniCS problem solving

From cb6c2f8291e937e9986ac3a155998549c1007e79 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 07:37:34 +0100
Subject: [PATCH 50/90] Try and fix just fenics-dolfinx

---
 .github/workflows/spack-matrix.yml | 359 +++++++++++++++--------------
 1 file changed, 180 insertions(+), 179 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 0a2059f4..e10ee3aa 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -34,23 +34,23 @@ jobs:
       - run: chmod +x style_check.sh
       - run: ./style_check.sh HEAD^
 
-  fenics-basix:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#  fenics-basix:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "0.10", "0.9", "0.8"]
+#        spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
 
   fenics-dolfinx:
     needs: style-check
@@ -75,11 +75,12 @@ jobs:
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
+        if: contains(matrix.spec, '%gcc@13')
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add catch2 cmake
-          spack load --first cmake
+          spack install --add catch2 cmake py-fenics-ffcx
+          spack load --first catch2 cmake py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
@@ -89,163 +90,163 @@ jobs:
           ctest -V --output-on-failure -R unittests_np_3
 
 
-  fenics-ufcx:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["%gcc@13"]
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: fenics-ufcx@${{ matrix.version }} ${{ matrix.spec }}
-
-  py-fenics-basix:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "0.10", "0.9", "0.8"]
-        # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
-        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %%clang@18 ^fenics-basix%clang@18"]
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-      - name: Run tests
-        if: ${{ matrix.version != '0.8' }}
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-          python -m pytest -n auto test/
-      # NOTE: 0.8 has test_all_elements_included broken
-      - name: Run tests
-        if: ${{ matrix.version == '0.8' }}
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-          python -m pytest -n auto -k "not test_all_elements_included" test/
-
-  py-fenics-dolfinx:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "0.10", "0.9", "0.8"]
-        python-version: ["3.10", "3.13"]
-        # NOTE: As of 2/2026 %clang@18 seems to create dependency on mpilander stub mpi or intelmpi.
-        # NOTE: Some overspecification of %clang@18 to fix ABI issues (std::string).
-        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-               "build_type=Developer %%clang@18 ^openmpi"]
-        # Test new superlu-dist variant
-        include:
-          - version: "main"
-            spec: "build_type=Developer %%clang@18 ^mpich-fortran ^fenics-dolfinx+superlu-dist"
-            python-version: "3.12"
-    env:
-      OMPI_ALLOW_RUN_AS_ROOT: 1
-      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
-      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
-      - name: Run tests
-        if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-      - name: Run tests
-        if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
-          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
-
-  py-fenics-ffcx:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "0.10", "0.9", "0.8"]
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: py-fenics-ffcx@${{ matrix.version }}
-      # NOTE: ffcx version 0.8 currently broken
-      - name: Run tests
-        if: ${{ matrix.version != '0.8' }}
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest py-sympy py-pytest-xdist
-          spack stage py-fenics-ffcx@${{ matrix.version }}
-          spack cd py-fenics-ffcx@${{ matrix.version }}
-          python -m pytest -n auto test/
-
-  py-fenics-ufl:
-    needs: style-check
-    runs-on: ubuntu-latest
-    container: ubuntu:24.04
-    strategy:
-      fail-fast: false
-      matrix:
-        version: ["main", "2025.2", "2025.1", "2024.2", "2024.1"]
-
-    steps:
-      - uses: actions/checkout@v5
-        with:
-          path: spack-fenics
-      - uses: ./spack-fenics/.github/actions/test-package
-        with:
-          spec: py-fenics-ufl@${{ matrix.version }}
-      - name: Run tests
-        shell: spack-bash {0}
-        run: |
-          spack env activate ./env
-          spack install --add py-pytest py-pytest-xdist
-          spack stage py-fenics-ufl@${{ matrix.version }}
-          spack cd py-fenics-ufl@${{ matrix.version }}
-          python -m pytest -n auto test/
+#  fenics-ufcx:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "0.10", "0.9", "0.8"]
+#        spec: ["%gcc@13"]
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: fenics-ufcx@${{ matrix.version }} ${{ matrix.spec }}
+#
+#  py-fenics-basix:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "0.10", "0.9", "0.8"]
+#        # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
+#        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %%clang@18 ^fenics-basix%clang@18"]
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#      - name: Run tests
+#        if: ${{ matrix.version != '0.8' }}
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest py-sympy py-pytest-xdist
+#          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#          python -m pytest -n auto test/
+#      # NOTE: 0.8 has test_all_elements_included broken
+#      - name: Run tests
+#        if: ${{ matrix.version == '0.8' }}
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest py-sympy py-pytest-xdist
+#          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+#          python -m pytest -n auto -k "not test_all_elements_included" test/
+#
+#  py-fenics-dolfinx:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "0.10", "0.9", "0.8"]
+#        python-version: ["3.10", "3.13"]
+#        # NOTE: As of 2/2026 %clang@18 seems to create dependency on mpilander stub mpi or intelmpi.
+#        # NOTE: Some overspecification of %clang@18 to fix ABI issues (std::string).
+#        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
+#               "build_type=Developer %%clang@18 ^openmpi"]
+#        # Test new superlu-dist variant
+#        include:
+#          - version: "main"
+#            spec: "build_type=Developer %%clang@18 ^mpich~fortran ^fenics-dolfinx+superlu-dist"
+#            python-version: "3.12"
+#    env:
+#      OMPI_ALLOW_RUN_AS_ROOT: 1
+#      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
+#      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+#      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+#      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
+#      - name: Run tests
+#        if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
+#          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+#          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+#          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+#          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+#      - name: Run tests
+#        if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
+#          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+#          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+#          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
+#          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
+#
+#  py-fenics-ffcx:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "0.10", "0.9", "0.8"]
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: py-fenics-ffcx@${{ matrix.version }}
+#      # NOTE: ffcx version 0.8 currently broken
+#      - name: Run tests
+#        if: ${{ matrix.version != '0.8' }}
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest py-sympy py-pytest-xdist
+#          spack stage py-fenics-ffcx@${{ matrix.version }}
+#          spack cd py-fenics-ffcx@${{ matrix.version }}
+#          python -m pytest -n auto test/
+#
+#  py-fenics-ufl:
+#    needs: style-check
+#    runs-on: ubuntu-latest
+#    container: ubuntu:24.04
+#    strategy:
+#      fail-fast: false
+#      matrix:
+#        version: ["main", "2025.2", "2025.1", "2024.2", "2024.1"]
+#
+#    steps:
+#      - uses: actions/checkout@v5
+#        with:
+#          path: spack-fenics
+#      - uses: ./spack-fenics/.github/actions/test-package
+#        with:
+#          spec: py-fenics-ufl@${{ matrix.version }}
+#      - name: Run tests
+#        shell: spack-bash {0}
+#        run: |
+#          spack env activate ./env
+#          spack install --add py-pytest py-pytest-xdist
+#          spack stage py-fenics-ufl@${{ matrix.version }}
+#          spack cd py-fenics-ufl@${{ matrix.version }}
+#          python -m pytest -n auto test/

From 221c5a42aed43c917dc47552f33b23a011c075e7 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 07:41:18 +0100
Subject: [PATCH 51/90] Don't use mpilander!

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index e10ee3aa..a8fb4cb6 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -60,7 +60,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %%clang@18", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+        spec: ["build_type=Developer %%clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From be326d777e6212427d5cfd33a32f86c213481241 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 15:55:06 +0100
Subject: [PATCH 52/90] Split lines

---
 .github/workflows/spack-matrix.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index a8fb4cb6..21e11258 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -60,7 +60,8 @@ jobs:
       fail-fast: false
       matrix:
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %%clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+        spec: ["build_type=Developer %%clang@18 ^openmpi",
+               "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From b8758f0d1f7568a87f673666b43b5137faac9e04 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 16:09:31 +0100
Subject: [PATCH 53/90] Fixes

---
 .github/workflows/spack-matrix.yml | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 21e11258..6977e84f 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -21,7 +21,8 @@ jobs:
       - uses: actions/checkout@v5
         with:
           fetch-depth: 2
-      - uses: actions/checkout@v5
+      - name: Fetch Spack CI scripts
+        uses: actions/checkout@v5
         with:
           repository: spack/spack
           ref: develop
@@ -59,9 +60,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        # Issue: clang sometimes likes stub or Intel MPI
+        # Issue: mpich tries to build fortran without installing python3.
         version: ["main", "0.10", "0.9", "0.8"]
         spec: ["build_type=Developer %%clang@18 ^openmpi",
-               "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+               "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich~fortran"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -69,7 +72,7 @@ jobs:
       OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
 
     steps:
-      - uses: actions/checkout@v5
+        uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
@@ -156,8 +159,9 @@ jobs:
 #      matrix:
 #        version: ["main", "0.10", "0.9", "0.8"]
 #        python-version: ["3.10", "3.13"]
-#        # NOTE: As of 2/2026 %clang@18 seems to create dependency on mpilander stub mpi or intelmpi.
-#        # NOTE: Some overspecification of %clang@18 to fix ABI issues (std::string).
+#        # Issue: Overspecification of %%clang@18 to fix ABI issues (std::string related?).
+#        # Issue: clang sometimes likes stub or Intel MPI.
+#        # Issue: mpich tries to build fortran without installing python3.
 #        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
 #               "build_type=Developer %%clang@18 ^openmpi"]
 #        # Test new superlu-dist variant

From 40d9782c1858b359e4b535ce89f6da99635fa130 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 16:59:16 +0100
Subject: [PATCH 54/90] fix

---
 .github/actions/test-package/action.yml | 12 ++----------
 .github/workflows/spack-matrix.yml      |  5 ++---
 2 files changed, 4 insertions(+), 13 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 3aa34be6..65239a40 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -12,11 +12,7 @@ runs:
       shell: sh
       run: |
         apt-get -y update
-        apt-get install -y bzip2 curl file git gzip make patch tar unzip xz-utils
-
-    - uses: actions/setup-python@v6
-      with:
-        python-version: 3.13
+        apt-get install -y file bzip2 ca-certificates g++ gcc gfortran git gzip lsb-release patch python3 tar unzip xz-utils zstd
 
     - name: Set up spack
       uses: spack/setup-spack@v2
@@ -25,13 +21,9 @@ runs:
         color: true
         path: spack
 
-    - name: Install gcc
-      shell: sh
-      run: apt-get install -y g++ gcc gfortran build-essential
-
     - name: Install clang-18
       shell: sh
-      run: apt-get install -y clang-18 gfortran
+      run: apt-get install -y clang-18
 
     - name: Add repos
       shell: spack-bash {0}
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 6977e84f..cec88144 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -63,8 +63,7 @@ jobs:
         # Issue: clang sometimes likes stub or Intel MPI
         # Issue: mpich tries to build fortran without installing python3.
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %%clang@18 ^openmpi",
-               "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich~fortran"]
+        spec: ["build_type=Developer %%clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -167,7 +166,7 @@ jobs:
 #        # Test new superlu-dist variant
 #        include:
 #          - version: "main"
-#            spec: "build_type=Developer %%clang@18 ^mpich~fortran ^fenics-dolfinx+superlu-dist"
+#            spec: "build_type=Developer %%clang@18 ^mpich ^fenics-dolfinx+superlu-dist"
 #            python-version: "3.12"
 #    env:
 #      OMPI_ALLOW_RUN_AS_ROOT: 1

From 8b2acff469e4d47442e8d8ef97e1580eaf542ad7 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 20:10:03 +0100
Subject: [PATCH 55/90] Fix.

---
 .github/workflows/spack-matrix.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index cec88144..e29fe5ba 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -61,7 +61,6 @@ jobs:
       fail-fast: false
       matrix:
         # Issue: clang sometimes likes stub or Intel MPI
-        # Issue: mpich tries to build fortran without installing python3.
         version: ["main", "0.10", "0.9", "0.8"]
         spec: ["build_type=Developer %%clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
@@ -71,13 +70,14 @@ jobs:
       OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
 
     steps:
-        uses: actions/checkout@v5
+      - uses: actions/checkout@v5
         with:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
+        # Out of disk error with clang
         if: contains(matrix.spec, '%gcc@13')
         shell: spack-bash {0}
         run: |

From 7a1c551908b504a345d561ca950a78900a12306c Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 21:02:49 +0100
Subject: [PATCH 56/90] Remove cache

---
 .github/actions/test-package/action.yml | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 65239a40..592e0cf4 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -32,12 +32,12 @@ runs:
         spack config get repos
         spack repo list
 
-    - name: add cache
-      shell: spack-bash {0}
-      run: |
-        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
-        spack buildcache keys --install --trust
-        spack config add "packages:all:target:[x86_64_v3]"
+#    - name: add cache
+#      shell: spack-bash {0}
+#      run: |
+#        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
+#        spack buildcache keys --install --trust
+#        spack config add "packages:all:target:[x86_64_v3]"
 
     - name: Compiler find
       shell: spack-bash {0}

From 9fa37e230306ccf552967d65bbc175289eae4bd6 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 21:58:41 +0100
Subject: [PATCH 57/90] Try not pushing clang down

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index e29fe5ba..056a5dd9 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,7 +62,7 @@ jobs:
       matrix:
         # Issue: clang sometimes likes stub or Intel MPI
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %%clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+        spec: ["build_type=Developer %clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From 58e3270247ebc04f79cbae8e30f229292d8f8851 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 22:08:31 +0100
Subject: [PATCH 58/90] Also try tests with clang

---
 .github/workflows/spack-matrix.yml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 056a5dd9..40946518 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -77,8 +77,6 @@ jobs:
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
-        # Out of disk error with clang
-        if: contains(matrix.spec, '%gcc@13')
         shell: spack-bash {0}
         run: |
           spack env activate ./env

From 1b02da20fe47de7bb92ab14909f1c31e92f48c3c Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 22:29:48 +0100
Subject: [PATCH 59/90] Why does it try gcc10!?

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 40946518..6740c3f9 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -80,7 +80,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add catch2 cmake py-fenics-ffcx
+          spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx %gcc@13 
           spack load --first catch2 cmake py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}

From 0e2da059ce5105e7646de6575cd1298d6c29f860 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Thu, 12 Feb 2026 22:31:05 +0100
Subject: [PATCH 60/90] try x86-v3

---
 .github/actions/test-package/action.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 592e0cf4..8d637eb1 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -32,12 +32,12 @@ runs:
         spack config get repos
         spack repo list
 
-#    - name: add cache
-#      shell: spack-bash {0}
-#      run: |
+    - name: add cache
+      shell: spack-bash {0}
+      run: |
+        spack config add "packages:all:target:[x86_64_v3]"
 #        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
 #        spack buildcache keys --install --trust
-#        spack config add "packages:all:target:[x86_64_v3]"
 
     - name: Compiler find
       shell: spack-bash {0}

From 9e894e67d406bac40cdb751520d5c0f94f75db03 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 13:04:25 +0100
Subject: [PATCH 61/90] Try getting it working on just gcc

---
 .github/workflows/spack-matrix.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 6740c3f9..dcb37e44 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,11 +78,12 @@ jobs:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
         shell: spack-bash {0}
+        if: contains(matrix.spec, "%gcc@13")
         run: |
           spack env activate ./env
-          spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx %gcc@13 
+          spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx
           spack load --first catch2 cmake py-fenics-ffcx
-          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} 
+          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
           cmake --build build/test

From ba4f8e34dbf9201354dd437f3eb89b8bc958b716 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 13:09:08 +0100
Subject: [PATCH 62/90] Fix quotes

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index dcb37e44..68a95ccc 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
         shell: spack-bash {0}
-        if: contains(matrix.spec, "%gcc@13")
+        if: contains(matrix.spec, '%gcc@13')
         run: |
           spack env activate ./env
           spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx

From 4ed4f853b621a1bd254166c9588b1530693bc66d Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 13:33:50 +0100
Subject: [PATCH 63/90] OK, don't install clang

---
 .github/actions/test-package/action.yml | 1 +
 .github/workflows/spack-matrix.yml      | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 8d637eb1..c239172e 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -23,6 +23,7 @@ runs:
 
     - name: Install clang-18
       shell: sh
+      if: contains(spec, '%clang')
       run: apt-get install -y clang-18
 
     - name: Add repos
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 68a95ccc..48e05678 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
         shell: spack-bash {0}
-        if: contains(matrix.spec, '%gcc@13')
+        if: contains(matrix.spec, '%gcc')
         run: |
           spack env activate ./env
           spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx

From ed282b40ab11c370520cdaea7799da6c20ddf6a0 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 14:16:32 +0100
Subject: [PATCH 64/90] Fix

---
 .github/actions/test-package/action.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index c239172e..99eba7ce 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -23,7 +23,7 @@ runs:
 
     - name: Install clang-18
       shell: sh
-      if: contains(spec, '%clang')
+      if: contains(inputs.spec, '%clang')
       run: apt-get install -y clang-18
 
     - name: Add repos
@@ -36,7 +36,7 @@ runs:
     - name: add cache
       shell: spack-bash {0}
       run: |
-        spack config add "packages:all:target:[x86_64_v3]"
+#        spack config add "packages:all:target:[x86_64_v3]"
 #        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
 #        spack buildcache keys --install --trust
 

From 4d3238350ac2de9fa39282e4f99648f0e82adfb2 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 14:31:25 +0100
Subject: [PATCH 65/90] Try Spack's buildcache

---
 .github/actions/test-package/action.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 99eba7ce..9301ee00 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -38,7 +38,8 @@ runs:
       run: |
 #        spack config add "packages:all:target:[x86_64_v3]"
 #        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
-#        spack buildcache keys --install --trust
+         spack mirror add develop https://binaries.spack.io/develop
+         spack buildcache keys --install --trust
 
     - name: Compiler find
       shell: spack-bash {0}

From 3c4f68924600bde50de60d54b4c5fee46a1fb32c Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 15:13:30 +0100
Subject: [PATCH 66/90] Fix syntax

---
 .github/actions/test-package/action.yml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 9301ee00..a243fac0 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -36,8 +36,6 @@ runs:
     - name: add cache
       shell: spack-bash {0}
       run: |
-#        spack config add "packages:all:target:[x86_64_v3]"
-#        spack mirror add e4s-25.11 https://cache.e4s.io/25.11
          spack mirror add develop https://binaries.spack.io/develop
          spack buildcache keys --install --trust
 

From a7a58cbd2ac820e1d42e35092b54ca583e626504 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 15:42:49 +0100
Subject: [PATCH 67/90] Fix - doesn't work with really old HDF5 version

---
 .github/workflows/spack-matrix.yml                   | 3 +--
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 3 ++-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 48e05678..28c92203 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,10 +78,9 @@ jobs:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
       - name: Run tests
         shell: spack-bash {0}
-        if: contains(matrix.spec, '%gcc')
         run: |
           spack env activate ./env
-          spack install --add catch2 %gcc@13 cmake %gcc@13 py-fenics-ffcx
+          spack install --add py-fenics-ffcx
           spack load --first catch2 cmake py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index 53dda50a..ee7d4661 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -69,7 +69,8 @@ class FenicsDolfinx(CMakePackage):
     depends_on("cmake@3.19:", when="@:0.8", type="build")
     depends_on("pkgconfig", type="build")
     depends_on("mpi")
-    depends_on("hdf5+mpi")
+    # HDF5Interface.cpp #if H5_VERSION_GE are not precise enough.
+    depends_on("hdf5+mpi@1.12:")
     depends_on("boost@1.70:")
     depends_on("boost@1.70:+timer", when="@:0.9")
     depends_on("pugixml")

From 8b4ec98796e6147ae4ba0ced000ac83582cfa427 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 15:58:02 +0100
Subject: [PATCH 68/90] Add catch2

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 28c92203..8424766e 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -80,7 +80,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-fenics-ffcx
+          spack install --add py-fenics-ffcx catch2
           spack load --first catch2 cmake py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}

From d9dd1d1824146b73aa5ac9fa006784b39d5bd959 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 15:59:03 +0100
Subject: [PATCH 69/90] The deps on basix is only transitive

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index ee7d4661..b1193233 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -88,8 +88,6 @@ class FenicsDolfinx(CMakePackage):
     depends_on("superlu-dist", when="+superlu-dist")
 
     for ver in ("main", "0.10", "0.9", "0.8", "0.7", "0.6"):
-        depends_on(f"fenics-ufcx@{ver}", when=f"@{ver}")
-        depends_on(f"fenics-basix@{ver}", when=f"@{ver}")
         depends_on(f"py-fenics-ffcx@{ver}", when=f"@{ver}", type="test")
     depends_on("catch2", type="test")
 

From dde5356f634739802d9c0193f2569c509f0358cc Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Fri, 13 Feb 2026 16:00:13 +0100
Subject: [PATCH 70/90] Backtrack

---
 spack_repo/fenics/packages/fenics_dolfinx/package.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/spack_repo/fenics/packages/fenics_dolfinx/package.py b/spack_repo/fenics/packages/fenics_dolfinx/package.py
index b1193233..ee7d4661 100644
--- a/spack_repo/fenics/packages/fenics_dolfinx/package.py
+++ b/spack_repo/fenics/packages/fenics_dolfinx/package.py
@@ -88,6 +88,8 @@ class FenicsDolfinx(CMakePackage):
     depends_on("superlu-dist", when="+superlu-dist")
 
     for ver in ("main", "0.10", "0.9", "0.8", "0.7", "0.6"):
+        depends_on(f"fenics-ufcx@{ver}", when=f"@{ver}")
+        depends_on(f"fenics-basix@{ver}", when=f"@{ver}")
         depends_on(f"py-fenics-ffcx@{ver}", when=f"@{ver}", type="test")
     depends_on("catch2", type="test")
 

From 955239c64168611e7fe8c4fbc66be3698c4cbfd7 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 10:01:01 +0100
Subject: [PATCH 71/90] Try this.

---
 .github/workflows/spack-matrix.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 8424766e..49644867 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -60,9 +60,10 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # Issue: clang sometimes likes stub or Intel MPI
+        # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
+        # NOTE: py-fenics-* must be built with same compiler as fenics-*.
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+        spec: ["build_type=Developer %clang@18 ^openmpi py-fenics-basix %clang@18 py-fenics-ffcx catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich py-fenics-basix %gcc@13 py-fenics-ffcx catch2"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -80,7 +81,6 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack install --add py-fenics-ffcx catch2
           spack load --first catch2 cmake py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}

From 2d1322285d9b65b552d3d2c368057e826370671e Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 10:12:37 +0100
Subject: [PATCH 72/90] Is it necessary if unifying the concretiser?

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 49644867..fd9f9156 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -63,7 +63,7 @@ jobs:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
         # NOTE: py-fenics-* must be built with same compiler as fenics-*.
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %clang@18 ^openmpi py-fenics-basix %clang@18 py-fenics-ffcx catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich py-fenics-basix %gcc@13 py-fenics-ffcx catch2"]
+        spec: ["build_type=Developer %clang@18 ^openmpi py-fenics-basix py-fenics-ffcx catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich py-fenics-basix py-fenics-ffcx catch2"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From c5892e9220127556f1881c30aefe5bcf0f99349a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 10:31:06 +0100
Subject: [PATCH 73/90] try this

---
 .github/workflows/spack-matrix.yml | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index fd9f9156..887bd69e 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -61,9 +61,11 @@ jobs:
       fail-fast: false
       matrix:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
-        # NOTE: py-fenics-* must be built with same compiler as fenics-*.
         version: ["main", "0.10", "0.9", "0.8"]
-        spec: ["build_type=Developer %clang@18 ^openmpi py-fenics-basix py-fenics-ffcx catch2", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich py-fenics-basix py-fenics-ffcx catch2"]
+        extra_spec: ["py-fenics-basix py-fenics-ffcx catch2"]
+        include:
+          - main_spec: "build_type=Developer %clang@18 ^openmpi"
+          - main_spec: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -76,14 +78,14 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} ${{ extra_spec }}
       - name: Run tests
         shell: spack-bash {0}
         run: |
           spack env activate ./env
           spack load --first catch2 cmake py-fenics-ffcx
-          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
-          spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }}
+          spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
+          spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
           cmake --build build/test
           cd build/test

From 7e807df1f96c7deb4bdced5bb30ebc2934d27d3a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 10:35:33 +0100
Subject: [PATCH 74/90] Fix.

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 887bd69e..ce780421 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -78,7 +78,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} ${{ extra_spec }}
+          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} ${{ matrix.extra_spec }}
       - name: Run tests
         shell: spack-bash {0}
         run: |

From c4f35074ba3b5bd78f7644d1fbcd585d8ddbdf91 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 11:00:09 +0100
Subject: [PATCH 75/90] Fix.

---
 .github/workflows/spack-matrix.yml | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index ce780421..ff136ba0 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,10 +62,7 @@ jobs:
       matrix:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
         version: ["main", "0.10", "0.9", "0.8"]
-        extra_spec: ["py-fenics-basix py-fenics-ffcx catch2"]
-        include:
-          - main_spec: "build_type=Developer %clang@18 ^openmpi"
-          - main_spec: "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"
+        main_spec: ["build_type=Developer %clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -78,7 +75,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} ${{ matrix.extra_spec }}
+          spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} py-fenics-ffcx catch2 cmake
       - name: Run tests
         shell: spack-bash {0}
         run: |

From 02b76ac10b820c64cd0213851779a344479a584a Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 11:01:57 +0100
Subject: [PATCH 76/90] Composite seems undesirable for debugging

---
 .github/actions/test-package/action.yml | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index a243fac0..519212af 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -6,7 +6,6 @@ inputs:
     required: true
     type: string
 runs:
-  using: "composite"
   steps:
     - name: Install dependencies
       shell: sh
@@ -33,7 +32,7 @@ runs:
         spack config get repos
         spack repo list
 
-    - name: add cache
+    - name: Add cache
       shell: spack-bash {0}
       run: |
          spack mirror add develop https://binaries.spack.io/develop

From 2e2bea78801fd4a802a25c7fa8cab25e048a3a78 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 11:05:10 +0100
Subject: [PATCH 77/90] OK, fine.

---
 .github/actions/test-package/action.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 519212af..911b27d7 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -6,6 +6,7 @@ inputs:
     required: true
     type: string
 runs:
+  using: "composite"
   steps:
     - name: Install dependencies
       shell: sh
@@ -46,7 +47,7 @@ runs:
       shell: spack-bash {0}
       run: spack env create -d ./env
 
-    - name: Add spec
+    - name: Add specs
       shell: spack-bash {0}
       run: spack -e ./env add ${{ inputs.spec }}
 

From d72bda4ff527616f8daadc62a675809b1a6d7f25 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 11:28:19 +0100
Subject: [PATCH 78/90] Explicitly load fenics-dolfinx

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index ff136ba0..da619ff4 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -80,7 +80,7 @@ jobs:
         shell: spack-bash {0}
         run: |
           spack env activate ./env
-          spack load --first catch2 cmake py-fenics-ffcx
+          spack load --first catch2 cmake fenics-dolfinx py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer

From 4db65d748803edb61b9c00965ce08300a5497505 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 12:15:17 +0100
Subject: [PATCH 79/90] Constrain to Ubuntu 24.04 cache packages

---
 .github/actions/test-package/action.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 911b27d7..fc1a9bce 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -37,6 +37,7 @@ runs:
       shell: spack-bash {0}
       run: |
          spack mirror add develop https://binaries.spack.io/develop
+         spack config add "packages:all:require:os=ubuntu24.04"
          spack buildcache keys --install --trust
 
     - name: Compiler find

From f4cb54ee086baa9802900b0b0c51ac1c5afcf311 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 12:16:45 +0100
Subject: [PATCH 80/90] Fix ubuntu for cache

---
 .github/actions/test-package/action.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index fc1a9bce..bf9395a9 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -37,7 +37,7 @@ runs:
       shell: spack-bash {0}
       run: |
          spack mirror add develop https://binaries.spack.io/develop
-         spack config add "packages:all:require:os=ubuntu24.04"
+         spack config add "packages:all:require:[os=ubuntu24.04]"
          spack buildcache keys --install --trust
 
     - name: Compiler find

From c3640456285a35469238448b4cd51deac496b8b9 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 12:44:17 +0100
Subject: [PATCH 81/90] Propogate compilers down DAG

---
 .github/actions/test-package/action.yml | 8 +++-----
 .github/workflows/spack-matrix.yml      | 2 +-
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index bf9395a9..3d972668 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -15,11 +15,9 @@ runs:
         apt-get install -y file bzip2 ca-certificates g++ gcc gfortran git gzip lsb-release patch python3 tar unzip xz-utils zstd
 
     - name: Set up spack
-      uses: spack/setup-spack@v2
+      uses: spack/setup-spack@v3
       with:
-        ref: develop
-        color: true
-        path: spack
+        spack_ref: develop
 
     - name: Install clang-18
       shell: sh
@@ -37,7 +35,7 @@ runs:
       shell: spack-bash {0}
       run: |
          spack mirror add develop https://binaries.spack.io/develop
-         spack config add "packages:all:require:[os=ubuntu24.04]"
+         spack config add "packages:all:require:['os=ubuntu24.04','target=x86_64_v3']"
          spack buildcache keys --install --trust
 
     - name: Compiler find
diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index da619ff4..a1d4bfee 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,7 +62,7 @@ jobs:
       matrix:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
         version: ["main", "0.10", "0.9", "0.8"]
-        main_spec: ["build_type=Developer %clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %gcc@13 ^mpich"]
+        main_spec: ["build_type=Developer %%c,cxx=clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%c,cxx=gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From edf31369f9a6388b4af73585a48ff940c0c4971d Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 12:52:28 +0100
Subject: [PATCH 82/90] Fix

---
 .github/actions/test-package/action.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/actions/test-package/action.yml b/.github/actions/test-package/action.yml
index 3d972668..ef0dbc62 100644
--- a/.github/actions/test-package/action.yml
+++ b/.github/actions/test-package/action.yml
@@ -21,7 +21,7 @@ runs:
 
     - name: Install clang-18
       shell: sh
-      if: contains(inputs.spec, '%clang')
+      if: contains(inputs.spec, 'clang@18')
       run: apt-get install -y clang-18
 
     - name: Add repos

From d3bbf587b18b2fa445fb0585ec8b10d4f600a329 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 15:09:31 +0100
Subject: [PATCH 83/90] Fix.

---
 .github/workflows/spack-matrix.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index a1d4bfee..bd1c8bc8 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,7 +62,7 @@ jobs:
       matrix:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
         version: ["main", "0.10", "0.9", "0.8"]
-        main_spec: ["build_type=Developer %%c,cxx=clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%c,cxx=gcc@13 ^mpich"]
+        main_spec: ["build_type=Developer %%c,cxx=clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%gcc@13 ^mpich"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
@@ -83,8 +83,8 @@ jobs:
           spack load --first catch2 cmake fenics-dolfinx py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
-          cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
-          cmake --build build/test
+          spack build-env fenics-dolfinx -- cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
+          spack build-env fenics-dolfinx -- cmake --build build/test
           cd build/test
           ctest -V --output-on-failure -R unittests_np_1
           ctest -V --output-on-failure -R unittests_np_3

From a87645398d67511b634458dbc23f6a05cbcd370e Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 16:24:52 +0100
Subject: [PATCH 84/90] Doesn't work as ffcx is not in build-env

---
 .github/workflows/spack-matrix.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index bd1c8bc8..34f8c300 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -83,8 +83,9 @@ jobs:
           spack load --first catch2 cmake fenics-dolfinx py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
-          spack build-env fenics-dolfinx -- cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
-          spack build-env fenics-dolfinx -- cmake --build build/test
+          source <(spack build-env --dump /dev/stdout fenics-dolfinx)
+          cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
+          cmake --build build/test
           cd build/test
           ctest -V --output-on-failure -R unittests_np_1
           ctest -V --output-on-failure -R unittests_np_3

From 22c034303d7bf7cef4f88c9769c64e16dc6c5575 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sat, 14 Feb 2026 16:43:53 +0100
Subject: [PATCH 85/90] openmpi cache looks fuller

---
 .github/workflows/spack-matrix.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 34f8c300..7c5a9e2c 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -62,7 +62,7 @@ jobs:
       matrix:
         # NOTE: clang sometimes likes stub or Intel MPI. Force MPI implementations.
         version: ["main", "0.10", "0.9", "0.8"]
-        main_spec: ["build_type=Developer %%c,cxx=clang@18 ^openmpi", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%gcc@13 ^mpich"]
+        main_spec: ["build_type=Developer %%c,cxx=clang@18 ^mpich", "build_type=Developer partitioners=kahip,parmetis,scotch +petsc +slepc +adios2 %%gcc@13 ^openmpi"]
     env:
       OMPI_ALLOW_RUN_AS_ROOT: 1
       OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1

From 8aec60a9c455f045f2e074203a7fcbd461a9f7d4 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sun, 15 Feb 2026 10:55:43 +0100
Subject: [PATCH 86/90] Trick doesn't work, split into file and source

---
 .github/workflows/spack-matrix.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 7c5a9e2c..4a91991b 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -83,7 +83,8 @@ jobs:
           spack load --first catch2 cmake fenics-dolfinx py-fenics-ffcx
           spack stage fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
           spack cd fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }}
-          source <(spack build-env --dump /dev/stdout fenics-dolfinx)
+          spack build-env --dump fenics-dolfinx-build-env.sh fenics-dolfinx
+          source fenics-dolfinx-build-env.sh
           cmake -B build/test/ -S cpp/test/ -DCMAKE_BUILD_TYPE=Developer
           cmake --build build/test
           cd build/test

From c52e0e9a84a57af006c146ad9d98b5a84ef8d5cf Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Sun, 15 Feb 2026 20:07:40 +0100
Subject: [PATCH 87/90] Reenable

---
 .github/workflows/spack-matrix.yml | 359 +++++++++++++++--------------
 1 file changed, 180 insertions(+), 179 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 4a91991b..bbbd5558 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -35,23 +35,23 @@ jobs:
       - run: chmod +x style_check.sh
       - run: ./style_check.sh HEAD^
 
-#  fenics-basix:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "0.10", "0.9", "0.8"]
-#        spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+  fenics-basix:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "0.10", "0.9", "0.8"]
+        spec: ["build_type=Developer %gcc@13", "build_type=Developer %clang@18"]
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
 
   fenics-dolfinx:
     needs: style-check
@@ -76,8 +76,10 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: fenics-dolfinx@${{ matrix.version }} ${{ matrix.main_spec }} py-fenics-ffcx catch2 cmake
-      - name: Run tests
+      # FFCx compilation of poisson.py fails in ffcx/codegeneration/C/finite_element.py
+      - name: Run tests (skip 0.8)
         shell: spack-bash {0}
+        if: ${{ matrix.version != '0.8' }}
         run: |
           spack env activate ./env
           spack load --first catch2 cmake fenics-dolfinx py-fenics-ffcx
@@ -92,164 +94,163 @@ jobs:
           ctest -V --output-on-failure -R unittests_np_3
 
 
-#  fenics-ufcx:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "0.10", "0.9", "0.8"]
-#        spec: ["%gcc@13"]
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: fenics-ufcx@${{ matrix.version }} ${{ matrix.spec }}
-#
-#  py-fenics-basix:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "0.10", "0.9", "0.8"]
-#        # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
-#        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %%clang@18 ^fenics-basix%clang@18"]
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-#      - name: Run tests
-#        if: ${{ matrix.version != '0.8' }}
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest py-sympy py-pytest-xdist
-#          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-#          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-#          python -m pytest -n auto test/
-#      # NOTE: 0.8 has test_all_elements_included broken
-#      - name: Run tests
-#        if: ${{ matrix.version == '0.8' }}
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest py-sympy py-pytest-xdist
-#          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-#          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
-#          python -m pytest -n auto -k "not test_all_elements_included" test/
-#
-#  py-fenics-dolfinx:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "0.10", "0.9", "0.8"]
-#        python-version: ["3.10", "3.13"]
-#        # Issue: Overspecification of %%clang@18 to fix ABI issues (std::string related?).
-#        # Issue: clang sometimes likes stub or Intel MPI.
-#        # Issue: mpich tries to build fortran without installing python3.
-#        spec: ["build_type=Developer +petsc4py +slepc4py %gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2",
-#               "build_type=Developer %%clang@18 ^openmpi"]
-#        # Test new superlu-dist variant
-#        include:
-#          - version: "main"
-#            spec: "build_type=Developer %%clang@18 ^mpich ^fenics-dolfinx+superlu-dist"
-#            python-version: "3.12"
-#    env:
-#      OMPI_ALLOW_RUN_AS_ROOT: 1
-#      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
-#      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
-#      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-#      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
-#      - name: Run tests
-#        if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-#          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-#          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-#          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-#          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-#      - name: Run tests
-#        if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
-#          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-#          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
-#          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
-#          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
-#
-#  py-fenics-ffcx:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "0.10", "0.9", "0.8"]
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: py-fenics-ffcx@${{ matrix.version }}
-#      # NOTE: ffcx version 0.8 currently broken
-#      - name: Run tests
-#        if: ${{ matrix.version != '0.8' }}
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest py-sympy py-pytest-xdist
-#          spack stage py-fenics-ffcx@${{ matrix.version }}
-#          spack cd py-fenics-ffcx@${{ matrix.version }}
-#          python -m pytest -n auto test/
-#
-#  py-fenics-ufl:
-#    needs: style-check
-#    runs-on: ubuntu-latest
-#    container: ubuntu:24.04
-#    strategy:
-#      fail-fast: false
-#      matrix:
-#        version: ["main", "2025.2", "2025.1", "2024.2", "2024.1"]
-#
-#    steps:
-#      - uses: actions/checkout@v5
-#        with:
-#          path: spack-fenics
-#      - uses: ./spack-fenics/.github/actions/test-package
-#        with:
-#          spec: py-fenics-ufl@${{ matrix.version }}
-#      - name: Run tests
-#        shell: spack-bash {0}
-#        run: |
-#          spack env activate ./env
-#          spack install --add py-pytest py-pytest-xdist
-#          spack stage py-fenics-ufl@${{ matrix.version }}
-#          spack cd py-fenics-ufl@${{ matrix.version }}
-#          python -m pytest -n auto test/
+  fenics-ufcx:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "0.10", "0.9", "0.8"]
+        spec: ["%gcc@13"]
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: fenics-ufcx@${{ matrix.version }} ${{ matrix.spec }}
+
+  py-fenics-basix:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "0.10", "0.9", "0.8"]
+        # Make sure fenics-basix and py-fenics-basix build with same compiler/ABI.
+        spec: ["+ufl %gcc@13 ^fenics-basix%gcc@13", "+ufl %clang@18 ^fenics-basix%clang@18"]
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+      - name: Run tests
+        if: ${{ matrix.version != '0.8' }}
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest py-sympy py-pytest-xdist
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          python -m pytest -n auto test/
+      # NOTE: 0.8 has test_all_elements_included broken
+      - name: Run tests
+        if: ${{ matrix.version == '0.8' }}
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest py-sympy py-pytest-xdist
+          spack stage py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          spack cd py-fenics-basix@${{ matrix.version }} ${{ matrix.spec }}
+          python -m pytest -n auto -k "not test_all_elements_included" test/
+
+  py-fenics-dolfinx:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "0.10", "0.9", "0.8"]
+        python-version: ["3.10", "3.13"]
+        # NOTE: Overspecification of %%clang@18 to fix ABI issues (std::string related?).
+        # NOTE: clang sometimes likes stub or Intel MPI.
+        spec: ["build_type=Developer +petsc4py +slepc4py %%gcc@13 ^petsc+mumps ^fenics-dolfinx+adios2 ^mpich",
+               "build_type=Developer %%clang@18 ^openmpi"]
+        # Test new superlu-dist variant
+        include:
+          - version: "main"
+            spec: "build_type=Developer %%clang@18 ^mpich ^fenics-dolfinx+superlu-dist"
+            python-version: "3.12"
+    env:
+      OMPI_ALLOW_RUN_AS_ROOT: 1
+      OMPI_ALLOW_RUN_AS_ROOT_CONFIRM: 1
+      PRTE_MCA_rmaps_default_mapping_policy: :oversubscribe   # Newer OpenMPI
+      OMPI_MCA_rmaps_base_oversubscribe: true                 # Older OpenMPI
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+      # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
+      - name: Run tests
+        if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest@8.4 py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
+      - name: Run tests
+        if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest py-scipy py-pytest-xdist ^python@${{ matrix.python-version }}
+          spack stage py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
+          python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
+          mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_symmetry_interior_facet_assembly[mesh1]" python/test/unit
+
+  py-fenics-ffcx:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "0.10", "0.9", "0.8"]
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: py-fenics-ffcx@${{ matrix.version }}
+      # NOTE: ffcx version 0.8 currently broken
+      - name: Run tests
+        if: ${{ matrix.version != '0.8' }}
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest py-sympy py-pytest-xdist
+          spack stage py-fenics-ffcx@${{ matrix.version }}
+          spack cd py-fenics-ffcx@${{ matrix.version }}
+          python -m pytest -n auto test/
+
+  py-fenics-ufl:
+    needs: style-check
+    runs-on: ubuntu-latest
+    container: ubuntu:24.04
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ["main", "2025.2", "2025.1", "2024.2", "2024.1"]
+
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: spack-fenics
+      - uses: ./spack-fenics/.github/actions/test-package
+        with:
+          spec: py-fenics-ufl@${{ matrix.version }}
+      - name: Run tests
+        shell: spack-bash {0}
+        run: |
+          spack env activate ./env
+          spack install --add py-pytest py-pytest-xdist
+          spack stage py-fenics-ufl@${{ matrix.version }}
+          spack cd py-fenics-ufl@${{ matrix.version }}
+          python -m pytest -n auto test/

From 7dd248667677abec0177a557c9bdfee8e5521314 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 16 Feb 2026 08:27:25 +0100
Subject: [PATCH 88/90] Use gcc for FFCx tests, skip ref count UFL test

---
 .github/workflows/spack-matrix.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index bbbd5558..237a55df 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -218,7 +218,7 @@ jobs:
           path: spack-fenics
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-ffcx@${{ matrix.version }}
+          spec: py-fenics-ffcx@${{ matrix.version }} %%gcc@13
       # NOTE: ffcx version 0.8 currently broken
       - name: Run tests
         if: ${{ matrix.version != '0.8' }}
@@ -246,6 +246,7 @@ jobs:
       - uses: ./spack-fenics/.github/actions/test-package
         with:
           spec: py-fenics-ufl@${{ matrix.version }}
+      # NOTE: Reference counting changed in Python 3.14, leading to test failure.
       - name: Run tests
         shell: spack-bash {0}
         run: |
@@ -253,4 +254,4 @@ jobs:
           spack install --add py-pytest py-pytest-xdist
           spack stage py-fenics-ufl@${{ matrix.version }}
           spack cd py-fenics-ufl@${{ matrix.version }}
-          python -m pytest -n auto test/
+          python -m pytest -n auto -k "not test_strip_form_arguments_strips_data_refs" test/

From ecfd057a52fccab895ad44376f58cf19cd2bcfc6 Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 16 Feb 2026 09:08:44 +0100
Subject: [PATCH 89/90] Try forcing Python to be built with GCC.

---
 .github/workflows/spack-matrix.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 237a55df..3fd29946 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -216,9 +216,10 @@ jobs:
       - uses: actions/checkout@v5
         with:
           path: spack-fenics
+      # NOTE: Python built with GCC, otherwise cffi can try for an odd compiler.
       - uses: ./spack-fenics/.github/actions/test-package
         with:
-          spec: py-fenics-ffcx@${{ matrix.version }} %%gcc@13
+          spec: py-fenics-ffcx@${{ matrix.version }} ^python %%gcc@13
       # NOTE: ffcx version 0.8 currently broken
       - name: Run tests
         if: ${{ matrix.version != '0.8' }}

From d768cc53a41a5d7aa5fa828a14f578e029316bda Mon Sep 17 00:00:00 2001
From: "Jack S. Hale" <mail@jackhale.co.uk>
Date: Mon, 16 Feb 2026 13:00:52 +0100
Subject: [PATCH 90/90] 0.8 tests ok but very very slow

---
 .github/workflows/spack-matrix.yml | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/spack-matrix.yml b/.github/workflows/spack-matrix.yml
index 3fd29946..1fbbb7b6 100644
--- a/.github/workflows/spack-matrix.yml
+++ b/.github/workflows/spack-matrix.yml
@@ -182,8 +182,8 @@ jobs:
         with:
           spec: py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
       # pytest@8.4 required for collision of [tool.pytest] and [tool.pytest.ini_options] since @9.0
-      - name: Run tests
-        if: ${{ matrix.version == '0.8' || matrix.version == '0.9'}}
+      - name: Run tests (0.9)
+        if: ${{ matrix.version == '0.9'}}
         shell: spack-bash {0}
         run: |
           spack env activate ./env
@@ -192,7 +192,8 @@ jobs:
           spack cd py-fenics-dolfinx@${{ matrix.version }} ${{ matrix.spec }} ^python@${{ matrix.python-version }}
           python -m pytest -n auto -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
           mpiexec -n 3 python -m pytest -m "not petsc4py and not adios2" -k "not test_cffi_expression and not test_cube_distance" python/test/unit
-      - name: Run tests
+      # NOTE: 0.8 tests run very slow - skip?
+      - name: Run tests (not 0.8 and not 0.9)
         if: ${{ matrix.version != '0.8' && matrix.version != '0.9'}}
         shell: spack-bash {0}
         run: |