Add UPX file compression

Author: 4q4r

Dockerfile

@@ -18,6 +18,7 @@ RUN --mount=type=cache,target=/var/cache/apk \
       build-base musl-dev pkgconf \
       openssl-dev openssl-libs-static \
       zlib-dev zlib-static \
+      upx \
     && update-ca-certificates
 
 RUN set -eux; \
@@ -65,6 +66,12 @@ RUN --mount=type=cache,target=/usr/local/cargo/registry \
       exit 1; \
     fi
 
+RUN set -eux; \
+    echo "=== Before UPX ===" && ls -lh /out/telemt; \
+    upx --ultra-brute --preserve-build-id /out/telemt; \
+    echo "=== After UPX ===" && ls -lh /out/telemt; \
+    echo "=== Integrity check ===" && upx -t /out/telemt
+
 FROM gcr.io/distroless/static:nonroot AS runtime
 
 STOPSIGNAL SIGINT