Highlights

• Snapshots become a content-addressed history rather than a single blob. commit/checkout store a session as deduplicated objects, so a fork or an incremental save costs only what changed. Adds SnapshotGraph for ancestry, diffs, reachability, and lazy fetch planning, plus a CheckoutPolicy capability gate that refuses to restore a session into an environment missing builtins or features it needs. Available from Rust, Python, and JavaScript (#2223).
• Bashkit now ships a native C API. Five platform archives expose a versioned libbashkit ABI with opaque handles, binary-safe VFS access, explicit ownership, runnable C examples, and SHA-256 checksums (#2238).
• One-shot CLI execution now behaves like a real shell invocation. Script arguments populate $0 and positional parameters, piped stdin reaches the script, and stdout/stderr stream before completion or resource-limit failure (#2234).
• Path expansion and malformed substitutions are safer and more compatible. Globs expand every path component, while invalid $(...) syntax now fails closed instead of inventing a command name for permission analysis (#2232, #2231).
• Arithmetic side effects no longer panic at 64-bit integer boundaries. Compound assignment and prefix/postfix increment and decrement now wrap with Bash-compatible integer semantics in both evaluator paths.
• Static analysis rejects malformed literal boundaries. Source bytes reserved as internal lexer/expansion sentinels and unterminated quote segments now fail analysis instead of being normalized into a command name that was not present in the script. Analysis also rejects malformed heredoc reinjection that inserts command-name characters. Script execution retains its existing control-byte behavior.

Breaking Changes

• Bash::snapshot() now writes the v2 content-addressed container. Existing snapshots still restore, but snapshots written by 0.15.0 require Bashkit 0.14.5 or newer. Upgrade rollback targets to 0.14.5 before producing v2 snapshots; re-snapshot before rolling back further. Future readers get the typed SnapshotTooNew { required, supported } error when an upgrade is required.
• Snapshot restore now checks runtime capabilities. restore_snapshot defaults to CheckoutPolicy::Superset; a runtime missing a builtin, feature, or filesystem capability recorded by the snapshot rejects it. Use restore_snapshot_with_policy(..., CheckoutPolicy::Force) only when the host deliberately accepts that mismatch. Removing or renaming a builtin can make older snapshots fail this check.
• Two typed snapshot errors were added to the exhaustive bashkit::Error enum. Rust callers that exhaustively match Error must handle SnapshotTooNew and SnapshotCapabilityMismatch.

What's Changed

• feat(c-api): add native C ABI (#2238) by @chaliy
• fix(deps): resolve Dependabot vulnerabilities (#2235) by @chaliy
• feat(cli): script arguments, stdin forwarding, and streaming output for one-shot mode (#2234) by @chaliy
• fix(glob): expand every path component, not just the trailing one (#2232) by @chaliy
• fix(parser): reject a malformed $(...) instead of splicing its literals (#2231) by @chaliy
• feat(snapshot): write v2 and expose the history API (#2223) by @chaliy

Full Changelog: https://github.com/everruns/bashkit/compare/v0.14.5...v0.15.0