| name | sounio-typeck-effects |
| description | Work on Sounio type checking and effect system (bidirectional inference, effect inference/enforcement, and type rules); use when editing `compiler/src/typeck/`, `compiler/src/types/`, `compiler/src/check/`, or `compiler/src/effects/`. |
Sounio Typeck + Effects
Overview
Make changes to the type system and effect checker without drifting toward Rust or weakening Sounio’s explicit-effects contract.
Workflow
1) Anchor to language identity and current reality
- Read
CLAUDE.md for Sounio-native syntax constraints.
- Check
compiler/docs/KNOWN_LIMITATIONS.md before implementing surface syntax the compiler doesn’t support yet.
- Treat
docs/spec/LANGUAGE_SPECIFICATION.md as aspirational when it disagrees with the compiler.
2) Identify what layer you’re changing
- Parser/AST shape:
compiler/src/parser/, compiler/src/ast/
- Type rules / inference:
compiler/src/check/, compiler/src/typeck/, compiler/src/types/
- Effects enforcement + inference:
compiler/src/effects/ and compiler/src/types/effects.rs
3) Protect effect soundness
- If an operation performs IO/mutation/allocation/etc, ensure the effect set includes it.
- If an operation changes epistemic confidence/provenance, decide whether it must be effectful and enforce it consistently.
4) Add high-signal tests
- Rust integration:
compiler/tests/ (e.g. semantic types and effects)
- Diagnostics expectations:
tests/ui/
- Language harness:
tests/run-pass/, tests/compile-fail/
References
- Typeck map:
references/typeck-navigation.md
- Effects map:
references/effects-navigation.md
- Claude command reference:
.claude/commands/sounio-effects.md
