Compiler Roadmap

This roadmap records implementation order. It does not define language semantics or move the v0 finish line. Source-language rules live in ../../spec, and the fixed v0 completion gates live in v0-closure.md.

Current Priority

The current priority is to make the standard-library-driven v0 subset reliable end to end:

1. 1. keep docs, spec, implementation status, and tests consistent
2. close accepted-but-not-buildable frontend/backend gaps with source-backed rejection diagnostics
3. continue aggregate ABI, ownership, and drop cleanup work
4. promote only stable std APIs into runtime support
5. keep LSP behavior tied to compiler facts

Recommended Work Order

1. 1. Frontend closure audit: enumerate parser-accepted forms and ensure each has resolver/typechecker facts or a stable rejection diagnostic.
2. Buildability boundary: stop unsupported runtime forms before IR/backend emission with diagnostics written in source-language terms.
3. Aggregate ABI and ownership: continue direct/indirect aggregate edges, field-level state, enum payload facts, aggregate cleanup, and drop glue.
4. Std runtime: keep development/std/ aligned with spec/11; promote env, richer Vec, file, path, or allocator APIs only when their runtime contract is stable.
5. Control-flow and collection promotion: broaden loops, match payloads, arrays, view iteration, and generic methods only with closure-matrix and test updates.
6. Release hardening: run the full closure suite, remove stale docs, and make diagnostics and LSP presentation coherent.

Constraints To Preserve

• Keep the compiler self-contained. Do not switch the current compiler line to LLVM or an external linker.
• Keep safety checks always enabled. Optimizers may remove checks only when they prove the trap condition impossible.
• Keep Nocter home deterministic: use NOCTER_HOME or the resolved compiler executable's parent, including normal PATH symlinks to .nocter/nocter; do not silently search unrelated directories.
• Keep target-dependent std declarations inside stable std files behind #target(...).
• Keep interface contract-only in v0. Do not introduce interface dispatch, bounds, or code reuse as a convenience for implementation.
• Keep literal definitions and generalized ... spread/capture out of v0. Treat them as post-v0 language design, not as std or LSP shortcuts.
• Keep bare string interpolation rejected by buildability until an explicit allocator source is designed.
• Keep LSP semantic tokens, hovers, definitions, references, symbols, and completions backed by resolver/typechecker facts.

Near-Term Open Work

• Update stale references whenever syntax changes remove old spellings.
• Broaden copy-aggregate and aggregate-slice runtime support only when ABI, ownership, and std tests agree.
• Promote non-copy Vec<T> storage only after per-element drop behavior is designed and tested.
• Promote payload enum runtime only after match/if-is payload binding facts and drop cleanup are stable.
• Promote std/process.env only after nested fallible/optional return lowering and process-context storage are ready.