Start here.
Ship with evidence.
New to Kofun? Follow the contributor path below to run the compiler, understand the repository, and make a checked change without guessing which source or test owns the behavior. The tracker snapshot observes main commit 54d4cef. Its full CI verification is success. “Active” means an executable gate exists; design documents and open issues never become implementation claims by implication.
Your first day, in order
Four short guides take you from checkout to a reviewable contribution.
Set up and run Kofun
Install the small toolchain, use the repository launcher, and get a checked program running.
Learn where work belongs
Trace commands through compiler stages, specifications, tests, libraries, tooling, and the site.
Make a verified change
Follow the recipe for your subsystem, select the right gate, and prepare a reviewable patch.
Check the real boundary
Separate active compiler evidence from focused checkpoints, design direction, and planned work.
The frozen compiler profile has reached its three-generation semantic fixed point. Full-language self-hosting, a general parser and type checker, and general ownership and law checking remain open.
Read the capability matrix →Curated guides
Authoritative Markdown from the language and site repositories, rendered with source ownership, status qualifiers, and local links preserved.
Getting started
From a clean machine to a checked compiler run and local documentation site.
Read document →Start hereRepository guide
A task-oriented map of every top-level area, compiler path, test family, and generated boundary.
Read document →Start hereImplemented status
The concise capability matrix. Active claims require an executable gate.
Read document →GuidesOne-day tutorial
An eight-hour learning path, with current compiler boundaries called out explicitly.
Read document →GuidesScientific computing
Long-range array, numerical computing, interoperability, and tooling design.
Read document →LanguageLanguage vision
The intended audience, product direction, values, and explicit non-goals.
Read document →LanguageSyntax guide
Current syntax direction and the boundary between accepted Core and planned language.
Read document →LanguageType system
Static typing direction, generics, ownership interaction, and current limits.
Read document →LanguageDecimal design
Exact base-10 representation, literals, rounding, fixed point, and law evidence.
Read document →LanguageMemory model
The read/edit/take ownership model and the distinction between design and active checks.
Read document →CompilerNative backends
Direct x86-64 and AArch64 ELF checkpoints, debug metadata, and bounded profiles.
Read document →CompilerCompiler architecture
Bootstrap layers, frontend artifacts, backends, and the trust boundary.
Read document →CompilerDeveloper discovery
One compiler-backed contract for inferred types, callable operations, and safe explanations.
Read document →CompilerSelf-hosting
The frozen profile, three-generation semantic fixed point, diverse double compilation, and independent-reproduction boundary.
Read document →ContributeContributing
Change recipes, test selection, repository conventions, review expectations, and definition of done.
Read document →ContributeIssue readiness
What the ready label means: one bounded artifact, a stamped current-behavior measurement, checkable criteria, and a named gate.
Read document →ProjectSpecification
Normative contracts, roadmap documents, and executable conformance evidence.
Read document →ProjectRoadmap
Milestone outcomes and the evidence required to advance project status.
Read document →ProjectSecurity
Threat boundaries, unsupported production claims, and hardening work.
Read document →ProjectRFC process
How public semantic decisions are proposed, reviewed, amended, and kept separate from whether anything was implemented.
Read document →ProjectRelease evidence
The machine-checked join between published capability claims and the gates, boundaries, and reproduction commands that bound them.
Read document →Evidence tracks
Tracker states observed on 2026-10-06; issue state may change between site versions.
GitHub Pages documentation site: publish a curated, honest docs site from docs/
Publish an honest, navigable documentation surface from repository sources.
Issue #666 · closedConformance: declare backend capabilities and execute numeric corpus on x86-64
Make backend conformance coverage explicit and execute numeric cases on direct x86-64 and AArch64.
Issue #667 · closedDiagnostics: add a compiler-wide registry and executable coverage gate
Connect every stable active diagnostic code to executable evidence and deterministic policy.
Issue #668 · closedSemantic fuzzing: define an oracle protocol and compare every declared backend
Compare declared backends through normalized observations and an independent family oracle.