[v1rtl]

Summary

• Replace ESLint with Biome 2 (recommended rules + import sorting; formatter matches existing style: single quotes, no semicolons, 2-space, 80 cols). Adds lint, format, typecheck scripts.
• Bump all devDeps: TypeScript 5.2 → 7.0, c8 8 → 12, @types/node 20 → 26.
• Drop tsup: pnpm build is now plain tsc -p tsconfig.build.json, emitting dist/index.js + dist/index.d.ts. The JS is no longer whitespace-minified.
• tsconfig: NodeNext (old Node resolution is deprecated) and strict.
• Source: import type, includes() instead of indexOf() !== -1, a Set for seen values, every() validation, template literals, slice, no assignment-in-condition, explicit return types. No behaviour change. Runtime output still needs only ES2016, so engines: >=12.20 holds.
• Tests: replace uvu + tsm with the built-in node:test runner (node --test), running the .ts files directly via Node's native type stripping (Node ≥22.18). Also node:assert, plus 4 new tests for vary(), which had none. 31/31 pass, 100% coverage via c8.
• CI: pnpm/setup@v3 installs pnpm and Node 24 in one step (and runs a frozen install with store caching), replacing actions/setup-node + pnpm/action-setup. checkout v7, coveralls v2. Lint and typecheck now run in CI.
• pnpm 10 → 12.15 (packageManager), lockfile regenerated; pnpm/setup requires pnpm ≥11.

https://claude.ai/code/session_01Cr1XmtnqJWfHjhrXu3mnPa

---

Generated by Claude Code

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	@​types/​node@​20.7.1 ⏵ 26.6.5			-1	-1
	c8@​8.0.1 ⏵ 12.0.0	+1		+1	+1
	typescript@​5.2.2 ⏵ 7.0.2			-1		+10
	@​biomejs/​biome@​2.6.3

View full report