HORUS v0.1.9-alpha

[neos-builder]

HORUS 0.1.9 Release Notes

Release Date: February 2026

Highlights

This release is a major cleanup and performance release — 77,000 lines of dead code removed, 43 bug/security fixes, and a redesigned Scheduler API with explicit opt-in for RT features.

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Breaking Changes

1. Scheduler: Lightweight new() + Opt-in RT

Scheduler::new() no longer auto-applies real-time features. It's now zero-cost (no syscalls).

// Before (0.1.8) — auto-applied RT priority, memory lock, CPU pin
let scheduler = Scheduler::new();

// After (0.1.9) — lightweight by default, opt-in to features
let scheduler = Scheduler::new()
    .realtime()        // RT priority + memory lock + CPU pin
    .with_blackbox(16) // 16MB flight recorder
    .tick_hz(1000.0);  // 1kHz tick rate

// Or use a preset:
let scheduler = Scheduler::deploy();           // Production: RT + BlackBox
let scheduler = Scheduler::safety_critical();  // WCET + watchdog + sequential
let scheduler = Scheduler::deterministic();    // Reproducible execution

New presets: deploy(), safety_critical(), high_performance(), hard_realtime(), deterministic()

Removed: prototype(), enable_determinism() (stub), name() (use with_name()), node() (use add_dyn())

2. Topic: 10 Dead APIs Removed

Removed unused network abstraction methods that had zero callers:

from_endpoint(), from_endpoint_with_capacity(), from_config_named(), from_config_file(), with_slot_size(), send_to_network(), recv_from_network(), network_has_messages(), network_backend_type(), migration_stats()

Core send()/recv() API is unchanged.

3. Message Types: Pod Suffix Removed

All message types are now zero-copy POD by default. The Pod suffix has been dropped:

Old	New
DetectionPod	Detection
Detection3DPod	Detection3D
BoundingBox2DPod	BoundingBox2D
BoundingBox3DPod	BoundingBox3D
SegmentationMaskPod	SegmentationMask
PathPlanPod	PathPlan

Duplicate non-Pod types have been deleted.

4. Error Handling

• Removed: HorusError::Other(String) catch-all
• Added: HorusError::Internal { message, file, line } and HorusError::Contextual { message, source }

5. Crate Reorganization

Module	Moved To
ML types	horus_ai (new crate)
IO types	horus-industrial (new crate)
Perception types	Merged into horus_library
ROS2/Zenoh bridge	Extracted to horus-ros2 registry package

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Performance

Optimization	Impact
Function pointer dispatch for send()/recv()	~15-20% faster hot path
DirectChannel inlined fast path	~3ns same-thread latency
Co-located SHM slot layout	Better cache locality
Batched header updates (every 32 msgs)	Less atomic contention
Parallel scheduler execution mode	Multi-core node execution
Per-node rate limiting	Independent tick rates per node

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Security & Bug Fixes (43 fixes)

Critical:

• Fix ABA bug in lock-free free list (tensor/CUDA pools)
• Fix alignment UB in PyTensorHandle::from_descriptor
• Fix soundness: Cell<u32> → AtomicU32 in ShmTopic
• Fix race condition in cross-process topic initialization
• Fix multi-producer race conditions in Topic
• Fix SIGSEGV from stale shared memory
• Fix socket fd leak in io_uring backend

Security hardening:

• Path traversal fixes in package install/uninstall and recording handlers
• Integer overflow fixes in 8+ locations
• UTF-8 safety for FixedString and string operations
• Unbounded allocation and fragment reassembly limits
• SAFETY comments added to all 338 unsafe blocks
• Updated vulnerable dependencies (RUSTSEC-2026-0002 and others)

Stability:

• Fix read_latest() returning None on ring buffer wrap
• Fix SPSC→MPSC migration header corruption
• Replace 4 production panics with proper error returns
• Fix heartbeat using hardcoded port instead of peer's actual port
• Fix TCP stream desync and division-by-zero issues

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New CLI Commands

• horus driver install/remove — Hardware driver management
• horus plugin install/remove — Plugin management
• horus env show/list — Environment info

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Python Bindings

• All new Scheduler presets and builder methods available in Python
• Node.tick() rate control now handled natively by horus_core
• Dead APIs removed to match Rust cleanup

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Code Quality

• -77,605 net lines removed across 298 files
• Cranelift JIT system removed (speculative, unused)
• CLI main.rs refactored: 6,442 → 2,084 lines
• Public API surface tightened — internal types no longer exposed
• get_ prefix removed from public API methods

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Migration Guide

// Scheduler: add .realtime() if you need RT features
Scheduler::new()                    // was auto-RT, now lightweight
Scheduler::new().realtime()         // explicit RT opt-in
Scheduler::deploy()                 // production preset

// Scheduler: use replacements for removed methods
Scheduler::deterministic()          // replaces enable_determinism()
Scheduler::new()                    // replaces prototype()
scheduler.with_name("MyBot")       // replaces name("MyBot")
scheduler.add_dyn(node)            // replaces node(node)

// Topic: use standard constructors
Topic::new("name", None)           // replaces from_endpoint()
Topic::with_capacity("name", 64, None) // replaces from_endpoint_with_capacity()

// Message types: remove Pod suffix
use horus::library::messages::detection::Detection;  // was DetectionPod

// Errors: use specific variants
HorusError::Communication(msg)     // replaces Other(msg)

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Coming Next

The HORUS registry will begin exposing external packages next week — including simulation environments, hardware drivers, and sensor integrations as installable packages via horus pkg install.

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For questions or issues: https://github.com/softmata/horus/issues

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This discussion was created from the release HORUS v0.1.9-alpha.