- Share frontend loading, package selection, contracts, and FFI parsing between Node and native clients.
- Preserve collection layouts and optional method returns while lowering long nullish chains without recursive stack growth.
- Rebuild the frontend from TypeScript through native lowering and C emission with matching output.
- Carry BigInts, Sets, and regular expressions through checked native storage without a JavaScript engine.
- Preserve dictionary aliases, spreads, frozen metadata, and fluent initialization helpers.
- Collect checked object and closure cycles while preserving live references.
- Store checked values in native collections while preserving supported object identities and JavaScript key equality.
- Support collection iteration and reject reference conversions that would copy or adapt stored objects.
Represent ordinary JavaScript arrays with hole, value, and explicit-undefined states; add sparse side storage and carry missing values through the frontend, native backends, runtime, and Node-facing consumers.
- Shard portable coverage across 16 sandboxes while retaining focused Darwin contracts.
- Run invariant suites once and keep differential and sanitizer-sensitive coverage in both lanes.
- Harden sandbox transport, exit-status parsing, and Linux runtime test portability.
Chris Tate