Monthly summary for 2025-05 (Leonidas-from-XIV/dune) focusing on Dune subst version-handling work: Key features delivered: - Robust version handling for dune subst in opam files and non-versioned projects, including safe handling when version information is missing or version control metadata is unavailable. Major bugs fixed: - Dune subst no longer fails when adding the version field in opam files; added fallback behavior to cope with missing version data. - Expanded test coverage to reproduce and verify the behavior, reducing regression risk (related to issue #11045). Overall impact and accomplishments: - Improves reliability of packaging and reproducible builds by ensuring consistent version resolution across varied project states, including environments without VCS data. - Strengthens version propagation by preferring the dune-project version when there is no VCS, ensuring stable release builds. - Demonstrated strong test-driven development and robust edge-case handling in version resolution. Technologies/skills demonstrated: - OCaml tooling, dune/subst internals, opam project handling, version resolution logic, and test coverage expansion.