Windows ARM64 build support: defense-in-depth atomic file ops and Python install error handling

flavorpack 2026-03-24

17 files · 3,034+ · 1,191-

5 files changed

builder_windows.go Defense-in-depth atomicReplace() with 4 fallback strategies for ARM64 file locking: MoveFileEx+retry, GC+handle cleanup, delete-then-move, verify replacement
builder_windows_test.go 328-line Windows ARM64 test suite for atomic file operations
builder.go Updated builder for ARM64 platform detection
03-flavor-pipeline.yml Added windows_arm64 to build matrix
release-pipeline.yml Added windows_arm64 to release pipeline

atomicReplace() on Windows now uses a four-strategy defense-in-depth approach: (1) MoveFileEx with progressive retry delays handles most cases; (2) explicit GC + extended delay handles ARM64’s stricter file handle lifecycle; (3) delete-then-move fallback for persistent locks; (4) final verify step asserts the replacement succeeded. Failing all four logs an error with source/dest paths. instantiate behavioral
2 files
- builder_windows.go
- builder_windows_test.go

1 file changed

environment_builder.py Strategy 1 (uv python install --install-dir) now wrapped in try/except; failures fall through to strategy 2 (default managed location) rather than crashing

Python installation strategy 1 wrapped in try/except Exception so failures (e.g. uv version incompatibilities or network issues) fall through to strategy 2 gracefully, with a diagnostic print, rather than raising and aborting the build. harden behavioral
1 file
- environment_builder.py

8 files changed

WINDOWS_ARM64_COMPLETION_REPORT.md 363-line completion report for Windows ARM64 implementation
WINDOWS_ARM64_BUILD.md 495-line Windows ARM64 build guide
LOCAL_TESTING_WINDOWS_ARM64.md 559-line local testing guide for Windows 11 ARM64
DEFENSE_IN_DEPTH_FILE_OPS.md 269-line defense-in-depth file operations documentation
CODE_COVERAGE_REGRESSION.md 365-line code coverage and regression testing guide
COVERAGE_ASSESSMENT.md 347-line honest coverage assessment
01-helper-prep.yml Minor CI prep updates
build_wheel.py Minor wheel build tool update

Added comprehensive docs: Windows ARM64 build guide, local testing guide, defense-in-depth file operations rationale, code coverage guide, and completion report. Coverage assessment documents known gaps honestly. specify internal
3 files
- WINDOWS_ARM64_BUILD.md
- LOCAL_TESTING_WINDOWS_ARM64.md
- DEFENSE_IN_DEPTH_FILE_OPS.md