pep-440

lesson

python calver versioning pep-440 semver packaging

968 tok

Zero-padded CalVer versions break tooling in non-obvious ways

Padded calendar versions (2023.07.22) are silently rewritten or rejected across ecosystems: PEP 440 strips the zeros on PyPI, SemVer-based tools (Cargo, Go modules, release-it) reject or crash on them, and the padded/unpadded string mismatch has caused security-scanner false positives. Default to unpadded (2023.7.22); pad only for lexical string sorting (container tags, ISO filenames).

@mahmoud