Kit Updated: 2026.6.22

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Kit 2026.6.22 is a correctness-heavy compiler and package release. It fixes function application semantics, Hindley-Milner substitution soundness, import qualification diagnostics, capability and active-pattern diagnostics, selective imports, exported type imports, and logger inference. It also resolves Git dependency version constraints and adds smaller ergonomics around Char literals and standalone checked type signatures.

What Changed

The compiler gets several targeted correctness fixes. Function application semantics are repaired, the HM substitution path is tightened for soundness, and logger inference now works with exported type imports. Import qualification and missing requested exports also produce better diagnostics, with selective imports loaded by the names a module actually asked for.

Diagnostics are sharper around capabilities and active patterns, and selective import checks are now stable in CI. The release also moves transient docs into notes and renames root examples into parity fixtures so executable examples and regression fixtures are less likely to drift.

Package development gets another cleanup pass. Git dependency version constraints are resolved during installs, and the package development sweep has been stabilized for the current first-party package set. The website package docs were regenerated from those package sources for this release.

Thanks to Greg ( prosumma) and Alvydas ( avitkauskas) for the issues they reported. Those reports helped narrow the diagnostics and package behavior fixed in this release.

The release also cleans the selfhost CI build cache and fixes an env substitution swap during selfhost. The site playground binary has been rebuilt from this release so kit version reports 2026.6.22 in WASM.

Release Highlights

• Fix function application semantics and HM substitution soundness.
• Improve import qualification, missing export, capability, and active-pattern diagnostics.
• Load selective imports by requested names and stabilize selective import CI checks.
• Resolve Git dependency version constraints during package installs.
• Fix exported type imports, logger inference, and selfhost env substitution.
• Add Char literal ergonomics and standalone checked type signatures.
• Regenerate package docs for the updated first-party package set.

Release Commits

The list below uses the v2026.6.19..v2026.6.22 changelog range, with each short SHA linked to the corresponding GitLab commit in kit-lang.

• Fix function application semantics (ca53bc2)
• Fix import qualification diagnostics (36d7265)
• Fix HM substitution soundness (96731b9)
• Fix capability and active-pattern diagnostics (144605e)
• Document stdlib pipe conventions (99642a1)
• Add Char literal ergonomics (6f1cdfa)
• Add standalone checked type signatures (969ee43)
• Resolve git dependency version constraints (effb4f2)
• Fix exported type imports and logger inference (a661c3e)
• Fix env substitution swap during selfhost (4112261)
• Clean selfhost CI build cache (8c4ba5d)
• Reload import cache for missing requested exports (95deb73)
• Load selective imports by requested names (1d88a97)
• Stabilize selective import CI checks (594827f)
• Move transient docs to notes (e30cbc0)
• Rename root examples to parity fixtures (f045db3)
• chore(release): bump version to 2026.6.21 (66b6fae)
• Stabilize package dev sweep (d4803cb)
• chore(release): bump version to 2026.6.22 (d0cc626)