1. This is a project for ww programming language
2. ww is a programming language aiming for Hare + CSP, no GC
3. cmd/ is the C bootstrap toolchain (wcc frontend lib, w6c/w6a/w6l per-arch, ww driver); selfhost/ is the ww reimplementation
4. All C code must strictly align with plan 9 coding style
5. lib/ is the standard library; follow Hare APIs (signatures, layout, error idioms) — consult ref/hare/ before designing new modules. Package declaration form is Go-style explicit `package foo;` and imports use `import foo;` (executables declare `package main;`) per language design (rob-pike + plan-9 sensibility); lib/ API surface still mirrors Hare.
6. ref/hare and ref/plan9front are read-only references — consult before inventing data shapes or syntax
7. No workarounds. If a bug forces a workaround, STOP and report with a precise repro. Document any retained divergence at the site with a pointer to the filed task. Never silent.
8. Comments are WHY-only. Never narrate WHAT the code does — names carry the WHAT. Comment only non-obvious WHY: a constraint, a divergence from a reference, a citation to a filed task.
9. Hare-fidelity over convenience. No ad-hoc extensions, renames, or convenience wrappers in lib/. Cite ref/hare/<module>/<file> for every signature ported. Carve-out: the Hare `_unsafe` suffix convention is dropped wholesale (ww is C/Plan-9-lineage, an unmanaged systems language — no GC, no "safe" baseline to be unsafe relative to). bytes→str is a pure reinterpret (`strings.frombytes`, renamed from Hare's `fromutf8_unsafe`); validation is opt-in via `utf8.validate(b)?` at the IO source, never wrapped per-construction. Rationale: ref/hare/strings/utf8.ha:10,22 — the suffix flags Hare's managed-bytes-safety axis, which ww doesn't have. The honest name (`frombytes`) reserves `fromutf8` for a future true validating helper.
10. Symmetric stages. cstage and wwstage MUST emit byte-identical asm for the same input. When inference power differs, align the richer side DOWN to the leaner side, not the other way.
11. Split commits when they bundle unrelated concerns. Bisect-cleanliness is the default. Multi-fix commits need a body paragraph explaining why they couldn't split.
12. Simple data, simple algorithms. Sea-of-stars style. Mirror Hare's structural choices over clever alternatives.
13. No hardcoded size literals in size-computation contexts. Always route through the type table (tinfo.size / Type.size / ty_*->size / size(T) / primtypesize / tyslicesize). Per Drew's framing of Hare's discipline. `make sizelint` enforces and runs as a dep of `make test`. Exemptions documented inline with `// sizelint-ok: <reason>` (ww) or `/* sizelint-ok: <reason> */` (C). Optional local enforcement: `ln -s ../../tools/sizelint .git/hooks/pre-commit`.