#molt version

Consume every pending changeset in one batch: bump versions, propagate to dependents, rewrite internal pins and changelogs, and update the lockfile.

#Synopsis

molt version [OPTIONS]

#Description

molt version drains the .changeset/ buffer. It reads all pending changesets, builds the release plan, and applies it:

• Bumps each package to its computed version, taking the highest bump among the changesets that touch it.
• Propagates through the dependency graph -- a dependent whose constraint no longer accepts the new version gets released too, and its pin is rewritten. See Dependency propagation.
• Rewrites internal dependency pins in every manifest section where a bumped package appears.
• Writes changelogs from the changeset summaries, correct Markdown emitted directly.
• Updates the lockfile (for uv, one uv lock call) so uv.lock never goes stale -- a Python-specific step changesets does not perform.
• Deletes the consumed changesets.

Running molt version with no pending changesets exits 1 with No unreleased changesets found. This is v3 semantics (v2 exited 0); CI pipelines must tolerate that code. See Versioning.

#Atomicity

All mutations are buffered and flushed together. Changelog generation runs first and acts as the transactional guard: if it fails, nothing is written to disk. A mid-run failure therefore never leaves you half-bumped with changesets still on disk, so re-running cannot double-bump. This fixes a known changesets footgun.

#Prereleases and snapshots

• --pre {a,b,rc,dev} produces a PEP 440 prerelease (1.1.0rc0, 1.1.0a1, 1.1.0.dev3). It is stateless -- there is no pre-mode and no pre.json. Run it again and the counter increments (rc0 to rc1); run plain molt version to finalize to the stable version. See Prerelease control and Prerelease mode.
• --snapshot produces a throwaway snapshot version for a branch or PR build, defaulting to a separate index rather than PyPI. See Snapshot releases.

#Options

#The --snapshot optional value

Because the parser cannot bind a space-separated optional value, molt accepts three forms:

molt version --snapshot              # unnamed snapshot
molt version --snapshot=pr-123       # named snapshot
molt version --snapshot-name pr-123  # named snapshot

The space form molt version --snapshot pr-123 is rejected with a message suggesting --snapshot=pr-123 or --snapshot-name pr-123.

--snapshot forces commit: false for the run and skips prerelease bookkeeping. Snapshot and --pre cannot be combined.

#Validation

molt version fails before writing when:

• --ignore is passed and ignore is set in the config (you can only use one of them at a time).
• An --ignore name is not in the project.
• A published dependent of a skipped package is not itself skipped -- molt names the dependent and asks you to add it to --ignore. Dev-dependency-only dependents and unversioned private packages are exempt.

#Exit codes

#Examples

Cut a normal release from all pending changesets:

molt version

Preview the plan without touching disk:

molt version --dry-run

Cut a release candidate, then iterate:

molt version --pre rc        # 1.1.0rc0
molt version --pre rc        # 1.1.0rc1
molt version                 # 1.1.0  (finalizes)

Cut a snapshot for a PR build:

molt version --snapshot=pr-123

Skip a package for this run only:

molt version --ignore internal-scratch

#See also

• Versioning -- the release-time guide.
• The release plan and Dependency propagation.
• Versioning and PEP 440, Prerelease mode, Snapshot releases.
• molt publish -- ship what version bumped.