# Handoff — 2026-09-16 — the sixth editor, Turbo JS

## State

Five files and one comment edited to count six editors; see the history entry of the same date. Uncommitted, on `main`, on top of the also-uncommitted ACP trace work of 2026-09-16 (see `2026-09-15-acp-commands-mentions.md`).

## Next steps

1. Commit alongside turbo-js's first commit. No tag needed — the editor pins `v0.8.0`, which exists.
2. Two library cycles turbo-js exposed, when wanted: (a) `lsp.Client.DidOpen`'s `languageId` should come from the profile rather than be `"go"`; (b) pull diagnostics — `textDocument/diagnostic`, advertised by a server's `diagnosticProvider` capability — which would let a JavaScript editor run on TypeScript 7's own server from a single `npm install -g typescript`. turbo-js's `internal/jslang/editor_test.go` is a ready-made harness for (b): point its profile at `/path/to/node_modules/.bin/tsc` with `--lsp --stdio` and the diagnostics test is the one that fails today.

## Watch out for

- `Register` replacing a built-in is now exercised by a shipping editor. A change to the built-in JavaScript scanner's *name* would silently stop turbo-js's override; its `Language` constant is `syntax.LanguageJavaScript` on purpose.