Config

Signet's house Biome preset and TypeScript bases, so an app extends one config instead of carrying a hand-copied one that drifts.

bun add -d @dapplelight/signet-config @biomejs/biome typescript

Biome

{
  "$schema": "https://biomejs.dev/schemas/2.5.14/schema.json",
  "extends": ["@dapplelight/signet-config/biome"],
  "files": { "includes": ["**", "!**/dist"] }
}

Needs Biome 2. The preset is the same config create-signet-app scaffolds and Signet lints itself with: 2-space indent, 100 columns, double quotes, no semicolons (asNeeded), organize imports on, useHookAtTopLevel as an error, noExplicitAny as a warning, Tailwind directives parsed in CSS. It turns on vcs.useIgnoreFile, so the repo needs a .gitignore.

Keep files, overrides and anything product-specific in your own biome.json; your settings win over the preset's.

The preset carries "root": false. That is for Signet's own repo, where the file sits in a subdirectory and would otherwise be rejected as a second root config. Biome does not inherit root through extends, so your config stays a root config (the test checks this).

TypeScript

{
  "extends": "@dapplelight/signet-config/tsconfig/react.json",
  "compilerOptions": {
    "paths": { "@/*": ["./src/*"] },
    "types": ["vite/client"]
  },
  "include": ["src"]
}

File	For	Adds to base
tsconfig/base.json	scripts, shared packages	—
tsconfig/react.json	Vite + React SPA	DOM libs, jsx: react-jsx
tsconfig/worker.json	Cloudflare Workers	no DOM (a Worker has no document)

base.json: strict, moduleResolution: "bundler", module: "ESNext", target and lib ES2022, isolatedModules, moduleDetection: "force", resolveJsonModule, noFallthroughCasesInSwitch, skipLibCheck, noEmit, and types: [].

• No baseUrl. TypeScript 7 removed it. paths resolve relative to the tsconfig that declares them, so declare paths in your own file.
• types is empty. List what you use: ["vite/client"], ["bun"], ["node"]. A types you set replaces the base's; it does not add to it.
• Workers need runtime types. worker.json deliberately has no DOM lib. Add "types": ["@cloudflare/workers-types"], or run wrangler types and add the generated worker-configuration.d.ts to include.
• Emitting? The bases set noEmit. A build config sets noEmit: false and its own outDir, declaration, and so on.

Reusable CI

Signet also ships .github/workflows/ci-bun.yml, a workflow_call workflow: checkout, setup-bun, install, lint, typecheck, test, and an optional build.

jobs:
  ci:
    uses: dapplelight/signet/.github/workflows/ci-bun.yml@main
    with:
      bun-version: 1.3.11 # default: latest
      working-directory: . # default
      fetch-depth: 0 # default 1; 0 for scripts that diff against the base branch
      build: true # default false; runs build-command
      test: bun test # every command is overridable; "" skips the step

The Signet repo is private, so this needs a one-off setting. On GitHub, open dapplelight/signet → Settings → Actions → General → Access, and choose "Accessible from repositories owned by the user 'dapplelight'". Until then a caller fails with "workflow was not found". The calling repos must be owned by the same account.

It covers what every repo repeats. Repo-specific jobs stay in the repo: app-a's e2e, type-ramp and app-a-rules checks, app-b's slop:ci, dup, Neon integration and PR risk label. (For app-b, slop:ci and dup can ride along: lint: bun run lint && bun run slop:ci && bun run dup.)

There is no shared deploy workflow: app-a deploys from deploy.yml (wrangler for the API Worker, Pages for four frontends), and app-b has no deploy workflow at all; it deploys with bun run api:deploy / web:deploy.

How app-a and app-b differ today

Surveyed 2026-09-24, read-only. Adopting the preset means deciding each row.

Biome

	Preset (house)	app-a	app-b
Biome schema	2.5.14	2.4.10	2.5.14
Semicolons	asNeeded	asNeeded	always
Quotes, indent, width	double, 2 spaces, 100	same	same
Trailing commas	default (all)	all (explicit)	all (explicit)
Recommended rules	default (on)	recommended: true	preset: "recommended"
Unused imports	default	warn	error, unused variables error too
useHookAtTopLevel	error	default	default
Organize imports	on	not set	on
CSS	Tailwind directives parsed	CSS lint + format off, *.css excluded	Tailwind directives parsed, noImportantStyles off
Extras	—	noArrayIndexKey, noNonNullAssertion, noAutofocus, useButtonType warn; four a11y rules off; useNodejsImportProtocol off; globals: ["process"]	noConsole off, but error in apps/api

app-b on semicolons: extending the preset reformats every file. Either run biome check --write once in its own commit, or keep "javascript": { "formatter": { "semicolons": "always" } } in its biome.json.

TypeScript

	Preset	app-a	app-b
Shape	base + react + worker	root base for packages; web and admin standalone; Astro apps extend astro/tsconfigs/strict	one root config; web extends it for Next
module	ESNext	ESNext	Preserve
jsx	react-jsx (react.json)	react-jsx	preserve (Next)
Emit	noEmit	root emits declarations, source maps, incremental	noEmit
types	[]	per app (vite/client, node, bun)	["bun"] at the root
Other	moduleDetection: force, noFallthroughCasesInSwitch	esModuleInterop, forceConsistentCasingInFileNames	—

Both are strict with moduleResolution: "bundler" and no baseUrl. A Next app extends react.json and sets "jsx": "preserve" plus the next plugin.

CI

	app-a	app-b
Trigger	pull requests to main	push to main and every PR
Bun	pinned 1.3.11	latest
Shape	parallel jobs: lint (full history), typecheck, web test, API test, build, e2e	one job: typecheck, lint, slop:ci, dup, test
Also	deploy.yml	neon-integration.yml, pr-risk.yml