June 2026 monthly summary for YosysHQ/yosys: Strengthened build reliability and macOS compatibility by enhancing the CMake build system and integrating Homebrew tooling. These changes reduce build-time failures due to outdated Bison and misaligned tool availability, streamline developer onboarding, and improve CI consistency across environments.

May 2026: Delivered a foundational modernization of the Yosys build and Windows portability improvements, establishing a more reliable, cross-platform foundation for future releases and packaging. The work focused on modernizing the build pipeline to enable easier maintenance, packaging, and compliance with modern C++ standards, while also hardening Windows/MSVC portability to reduce platform-specific failures.

Month: 2025-07 — Focus on cross-platform portability for fmtlib/fmt. Key features delivered: WASI Compatibility Fix enabling broader WASI deployments by excluding unsupported system calls via conditional compilation, reducing runtime errors. Major bugs fixed: Stabilized behavior in WASI environments, preventing deployment-time failures. Overall impact: Expanded deployment options for fmt, reduced integration risk and support burden, improved portability and reliability across WASI-enabled platforms. Technologies/skills demonstrated: Cross-platform C++ library maintenance, conditional compilation, WASI environment awareness, and disciplined change management.

January 2025 — YosysHQ/yosys: Strengthened correctness and UX through CI sanitization and a backend text fix. Implemented UBSAN-based undefined behavior detection in CI by updating the test-build workflow to set SANITIZER=undefined and configuring UBSAN_OPTIONS=halt_on_error=1 for clang builds. Fixed a user-facing bug in the write_json backend by adding the missing newline to help text, improving display. These changes were driven by commit f5c53a99e76cef918b01e8b1b773c6be7b18e1e0 and 3076803c9e3742859e42a00c62af9441fb8b9339. Impact: earlier defect detection, more stable builds, and a clearer UX for developers and users.

December 2024 (Month: 2024-12) – YosysHQ/yosys: Delivered a user-facing UX improvement for the Smtbmc backend by updating the help text to include cvc5 as a supported SMT solver. The change is non-functional and does not alter runtime behavior; it aligns help messages with current capabilities and documentation, reducing user confusion and supporting smoother adoption of cvc5. The work was implemented via commit 1ef4c7f56553e1042f1878a021f37f60b0fc4acb.

Month 2024-11: Delivered a robust fix in the Cxxrtl backend to correct scope information for parameterized modules by stripping the $paramod suffix from module names derived from the hdlname attribute. This resolves module identification issues and improves accuracy for parameterized designs, reducing downstream debugging and integration risk. The change is implemented as a single commit and strengthens backend reliability for Yosys's Cxxrtl flow.