stack

Stack & library preferences

The defaults I reach for. Not dogma — pick the right tool per project — but this is the starting point unless there's a reason to deviate.

Core stack

Concern	Default	Notes
Runtime & package manager	Bun	bunfig.toml with isolated linker. bun i, bun test, bun run.
Language	TypeScript, strict, ESM	"type": "module", nodenext, verbatimModuleSyntax, .ts extension imports.
Type checker	TypeScript 7 (native tsc)	TS7 ships the native (Go) compiler as tsc — no separate tsgo binary. typecheck script is tsc. In the editor: TypeScriptTeam.native-preview + js/ts.experimental.useTsgo (see ide/).
Lint + format	Biome v2	One tool, replaces ESLint and Prettier. Never add Prettier.
Testing	bun test	Config in bunfig.toml (onlyFailures = true). Vitest only for non-Bun libs.
E2E	Playwright	Its own e2e/ workspace + a CI job.
Build	match the artifact, ESM-only	tsdown or bun build --compile for Bun libs/CLIs; Vite/esbuild for extensions. Ship ESM only — no CJS/dual publishing. Typecheck (noEmit) is separate from build.
Release	Tegami	Successor to Changesets. npm trusted publishing via OIDC.
Git hooks	husky + lint-staged	biome check --write on staged files.

Monorepo layout

Bun workspaces: packages/*, examples/*, plus docs/website when there are docs. Root package.json is "private": true, named @<project>/root. Scoped packages @<project>/<pkg>.

Dev/prod dual resolution — the signature trick. Publishable packages export a custom <pkg>@dev condition that points at raw .ts source, so dev and tests run source directly while consumers get built dist:

// package.json exports
"exports": {
  ".": {
    "<pkg>@dev": "./src/index.ts",
    "import": { "types": "./dist/index.d.mts", "default": "./dist/index.mjs" },
    "source": "./src/index.ts"
  }
}

Paired with tsconfig.json "customConditions": ["<pkg>@dev"] and bun test --conditions=<pkg>@dev. This flag is critical — without it tests resolve to stale dist.

Script vocabulary

Keep script names consistent across repos: start, dev, typecheck (tsc), lint / format / check / fix (Biome), test, and the composite gate checks = bun check && bun typecheck && bun run test. prepare: husky, tegami: bun scripts/tegami.mts.

Libraries by need

• Schema / validation: Zod v4 — always import * as z from 'zod/v4' (Biome-enforced). Use @standard-schema/spec for schema-agnostic public APIs.
• Web / sites: Astro (v6) + MDX/RSS/sitemap, deployed to GitHub Pages. React 19 (react-jsx runtime).
• Styling / UI: Tailwind CSS v4 (@tailwindcss/vite), shadcn, clsx + tailwind-merge, class-variance-authority / tailwind-variants, tw-animate-css. @base-ui/react for primitives. Icons via react-icons or lucide-react. Fonts via @fontsource-variable/geist.
• Utilities: es-toolkit (not lodash), immer.
• AI: Vercel ai SDK.
• Desktop / native: Tauri 2 (Rust); Zig for native bits.
• Testing libs: @testing-library/react + happy-dom; Remotion for video examples.

Setup instructions per archetype

• Bun library / CLI monorepo — the dominant style. Everything above applies. Start from config/package.template.json, add packages/<pkg> with the dev/prod-condition exports.
• Standalone ESM library — single package, ESM-only ("type": "module", exports with an import condition only, no main/CJS). Build dist with tsdown. Don't dual-publish CJS — consumers on modern Node/Bun don't need it.
• VS Code extension — Vite lib mode or esbuild, vscode externalized. ESLint is tolerated here (the one place Biome doesn't fully fit).
• Astro site — extends: astro/tsconfigs/strict, Tailwind v4, shadcn, deploy to Pages.