chore(deps): upgrade typescript to 7, drop the tsgo preview#110

typescript 5.9.3 -> 7.0.2, the native Go compiler. tsc and tsgo are now the same binary.

depends on #109 — eslint was the only thing in the tree reading the removed JS compiler API.

speed, measured on this repo

390 project files, cold (tsconfig.tsbuildinfo deleted between every run, 3 runs each):

~6x faster. note incremental: true is on, so a warm run was already ~1.1s under 5.9 — the 6x is the cold/CI number, which is the one that matters for the CI typecheck job.

redundancy removed

TS 7 is tsgo, so the parallel preview setup no longer has a reason to exist:

• dropped @typescript/native-preview devDep (was pinned to a 7.0.0-dev nightly)
• dropped the typecheck:fast script and its mise task/alias tcf
• dropped the "Typecheck (tsgo, informational)" CI job — the authoritative job now runs the same compiler
• dropped .tsgo-cache/ from .gitignore and the oxfmt ignore list
• AGENTS.md (and CLAUDE.md, its symlink) no longer mention typecheck:fast

the archived plan at .agents/plans/archive/tooling-tsgo-local-typecheck.md called this shot — it listed eslint's <6.1.0 pin as the reason tsgo had to ship as a separate package, and said to revisit when tsgo stabilised. this is that revisit.

verification

• tsc --noEmit — clean, and tsc --version reports 7.0.2
• 203/203 tests pass
• bun run build succeeds
• convex codegen --typecheck enable passes and leaves no _generated churn — worth calling out because the archived plan flagged convex's ts-morph codegen as a TS-API consumer. it isn't affected
• oxfmt --check clean

what to watch

typescript is now ^7.0.2 — a major with no JS compiler API. if any future dependency needs require("typescript") to return a real compiler, it won't work. nothing in the tree does today, verified after a clean rm -rf node_modules && bun install: no eslint, no @typescript-eslint, no typescript-eslint anywhere in node_modules or bun.lock.

one near-miss worth recording: convex-helpers@0.1.120 declares typescript: "^5.5 || ^6.0.0", which 7.0.2 falls outside. it's a non-issue — that peer is marked optional (peerDependenciesMeta.typescript.optional), it's transitive via @convex-dev/resend rather than a direct dep, and it contains no TypeScript API usage at all. bun emits no warning. flagging it only so the next person who greps peer ranges doesn't think it's a problem.

RNGO-48 · part of RNGO-40 (dependency upgrade sweep) https://linear.app/mihaicrisan/issue/rngo-48/upgrade-to-typescript-7-native-compiler-drop-tsgo-preview-pr