Kit Updated: 2026.7.12

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Kit 2026.7.12 strengthens native package delivery, makes FFI failures much easier to diagnose, expands package and cache maintenance commands, and moves the self-hosted compiler from a prototype toward a measurable release gate. It also closes a concentrated set of parser, trait, bytecode, arithmetic, and lint correctness gaps while continuing the runtime's work on faster lists, monomorphic tail calls, and escape-aware value representation.

What Changed

Native package manifests can now describe platform-specific native sections, and the installer carries prebuilt FFI artifacts through the full install flow instead of dropping or mis-linking them. Wrapper libraries receive a proper soname, Linux native linking now closes both direct and transitive gaps, and macOS framework flags are emitted only on macOS. Cached interpreter wrappers are checked for the symbols a package actually needs, generated C shims coerce integer arguments to their @cImport parameter types, and concurrent FFI compilations use unique temporary directories. When any of those steps fails, kit test and kit install surface the native failure rather than collapsing it into a bare panic.

Package and cache maintenance are more direct. kit list now folds source-package and orphan views into the main command, the codegen cache automatically prunes stale entries, and cache inspection and cleanup commands have been re-landed. Standard-library synchronization also refuses to downgrade an installed copy when an older compiler is used. The compiler repository itself adopted a Jujutsu-only workflow with verified land and hygiene helpers, making local release state easier to audit.

A focused correctness pass resolves eight findings reported by Greg. Thank you, Greg, for taking the time to exercise the 2026.7.8 release and write up the failures. Brace-form extend T with Trait { ... } bodies now register their implementations, bare trait method calls dispatch from the first argument's type, overlapping implementations are rejected, and binding bodies may begin on the next indented line. Integer overflow is consistently reported as E003 by the interpreter, bytecode VM, and compiled backend; bytecode programs now invoke their entry closure with Env when required; and linting correctly handles builtin-member shadowing, qualified-binding uses, and bare imports shadowed by top-level bindings.

The self-hosted compiler gained an opt-in kit selfhost command, a parity matrix, a corpus runner covering examples, the standard library, and packages, source-positioned diagnostics, performance budgets, and a tag-pipeline release preflight. Its frontend and code generator now understand substantially more of Kit: closure capture through lambda lifting, import-aware constructors and re-exports, record spread and destructuring, traits and derives, macros, patterns, heredocs and characters, list comprehensions, short-circuit operators, numeric widening, extern declarations, and self-recursive tail-call optimization. These are readiness milestones, not a claim that the production compiler has switched over; the release keeps the bootstrap gated by explicit parity and performance evidence.

Runtime and codegen work continues alongside self-hosting. Compiled lists now use thread-local headroom buffers for O(1) cons, self-host parser phases use linear-memory accumulation strategies, allocation failures abort with labeled out-of-memory diagnostics, and float zero has one canonical display form with valid generated Zig literals. Monomorphic scalar self-recursion gets tail-call optimization, while the new value-representation classifier and escape analysis establish the first phase of carrying proven scalar values without unnecessary boxing.

The website package docs were regenerated from all 123 first-party packages, and the playground WASM interpreter was rebuilt so kit version reports 2026.7.12.

Release Highlights

• Add platform-specific native manifest sections and preserve prebuilt FFI artifacts through installation.
• Surface native build/link failures from kit test and kit install with actionable diagnostics.
• Close Linux and macOS native-linking gaps, validate cached wrappers, and isolate concurrent FFI builds.
• Fold source and orphan package views into kit list; restore cache pruning and maintenance commands.
• Add the opt-in kit selfhost command, parity/corpus harnesses, performance budgets, and release preflight.
• Fix trait registration and bare-method dispatch, reject overlapping implementations, and allow next-line binding bodies.
• Report integer overflow as E003 consistently across all three execution backends.
• Auto-invoke bytecode entry closures with Env and correct three lint-analysis edge cases.
• Make compiled list cons O(1), add monomorphic scalar TCO, and introduce escape-aware value representation.
• Regenerate 123 package documents and rebuild the playground WASM binary for 2026.7.12.

Selected Release Commits

The full v2026.7.8..v2026.7.12 range contains 83 changelog entries. These commits mark the release's main user-visible changes; the complete ordered list remains in the project changelog.

• f493159 — platform-specific native manifest sections
• c7578cc — surface native FFI failures from tests and installs
• 4327cc8 — emit framework flags only on macOS
• d65761e — preserve native FFI artifacts during installation
• 7002635 — restore cache auto-pruning and maintenance commands
• 5d97371 — integrate source and orphan views into kit list
• 35bea33 — close Linux native-linking gaps
• af7a462 — validate cached Zig FFI wrapper exports
• e8db4f4 — coerce extern-C integer arguments correctly
• b45b262 — canonical float-zero display and valid Zig literals
• 998aad2 — add the opt-in kit selfhost command
• 2f2245a — add the self-host parity matrix
• f346761 — add the self-host corpus runner
• 8d8feaa — gate release docs with self-host preflight
• 1e9c2a6 — O(1) compiled list cons
• fd443fe — resolve all eight 2026.7.8 findings reported by Greg
• 595de94 — self-host macro declarations and substitution expansion
• 71d939b — self-recursive tail-call optimization in self-host codegen
• 16c0093 — labeled out-of-memory failures
• 3a5a8a5 — prevent standard-library downgrades during sync
• 414bf56 — monomorphic scalar TCO and value-representation groundwork
• a65a619 — escape-aware value-representation classifier