Convert from npm to bun

.github/workflows/pr.yaml

@@ -15,26 +15,22 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Check formatting with Prettier
         working-directory: ./app
-        run: npm run prettier
+        run: bun run prettier
 
       - name: Run ESLint
         working-directory: ./app
-        run: npm run eslint
+        run: bun run eslint
 
   typecheck:
     name: Type checking
@@ -44,22 +40,18 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Run TypeScript type checks
         working-directory: ./app
-        run: npm run typecheck
+        run: bun run typecheck
 
   test:
     name: Tests
@@ -69,25 +61,21 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Run design system tests
-        run: npm test --workspace=@policyengine/design-system
+        run: bun run test --filter=@policyengine/design-system
 
       - name: Run app tests
         working-directory: ./app
-        run: npm test
+        run: bun run test
 
   build:
     name: Build
@@ -97,19 +85,15 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Build application
         working-directory: ./app
-        run: npm run build
+        run: bun run build

.github/workflows/publish-design-system.yaml

@@ -43,19 +43,22 @@ jobs:
           fetch-depth: 0
           persist-credentials: false
 
-      - name: Setup Node.js
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
+
+      - name: Setup Node.js for npm publish
         uses: actions/setup-node@v4
         with:
           node-version: "22"
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run build --workspace=@policyengine/design-system
+        run: bun run build --filter=@policyengine/design-system
 
       - name: Run tests
-        run: npm run test --workspace=@policyengine/design-system
+        run: bun run test --filter=@policyengine/design-system
 
       - name: Release
         run: npx semantic-release

.github/workflows/push.yaml

@@ -14,26 +14,22 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Check formatting with Prettier
         working-directory: ./app
-        run: npm run prettier
+        run: bun run prettier
 
       - name: Run ESLint
         working-directory: ./app
-        run: npm run eslint
+        run: bun run eslint
 
   typecheck:
     name: Type checking
@@ -43,22 +39,18 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Run TypeScript type checks
         working-directory: ./app
-        run: npm run typecheck
+        run: bun run typecheck
 
   test:
     name: Tests
@@ -68,25 +60,21 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Run design system tests
-        run: npm test --workspace=@policyengine/design-system
+        run: bun run test --filter=@policyengine/design-system
 
       - name: Run app tests
         working-directory: ./app
-        run: npm test
+        run: bun run test
 
   build:
     name: Build
@@ -96,19 +84,15 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-          cache: 'npm'
-          cache-dependency-path: package-lock.json
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
 
       - name: Install dependencies
-        run: npm ci
+        run: bun install --frozen-lockfile
 
       - name: Build design system
-        run: npm run design-system:build
+        run: bun run design-system:build
 
       - name: Build application
         working-directory: ./app
-        run: npm run build
+        run: bun run build

.gitignore

@@ -21,6 +21,7 @@ yarn-debug.log*
 yarn-error.log*
 lerna-debug.log*
 .pnpm-debug.log*
+bun-debug.log*
 
 # Editor directories and files
 .vscode/*

CLAUDE.md

@@ -77,6 +77,6 @@ const PolicyEngineLogo = '/assets/logos/policyengine/white.svg';
 
 ## Before Committing
 
-1. Run `cd app && npm run prettier -- --write .` to format
-2. Run `npm run lint` to check for errors
+1. Run `cd app && bun run prettier -- --write .` to format
+2. Run `bun run lint` to check for errors
 3. CI uses `--max-warnings 0` so fix all warnings

Makefile

@@ -13,31 +13,31 @@ help:
 	@echo "  make deploy     - Build and deploy to GitHub Pages"
 
 install:
-	npm install
+	bun install
 
 dev:
-	npm run dev
+	bun run dev
 
 build:
-	cd app && npm run build-with-types
+	cd app && bun run build-with-types
 
 typecheck:
-	cd app && npm run typecheck
+	cd app && bun run typecheck
 
 test-all:
-	cd app && npm run test-all
+	cd app && bun run test-all
 
 test:
-	cd app && npm run test
+	cd app && bun run test
 
 lint:
-	cd app && npm run lint
+	cd app && bun run lint
 
 format:
-	cd app && npm run prettier:write
+	cd app && bun run prettier:write
 
 clean:
 	rm -rf app/dist app/node_modules node_modules packages/*/node_modules
 
 deploy: build
-	@echo "Build complete. GitHub Actions will handle deployment"
+	@echo "Build complete. GitHub Actions will handle deployment"

README.md

@@ -6,8 +6,7 @@ A modern web application for policy analysis and simulation, built with React, T
 
 ### Prerequisites
 
-- Node.js 20 or higher
-- npm
+- Bun 1.0 or higher (https://bun.sh)
 
 ### Installation
 

app/package.json

@@ -7,22 +7,22 @@
     "dev": "node scripts/dev-server.mjs",
     "dev:website": "VITE_APP_MODE=website vite",
     "dev:calculator": "VITE_APP_MODE=calculator vite",
-    "build": "npm run build:website && npm run build:calculator",
+    "build": "bun run build:website && bun run build:calculator",
     "build:calculator": "VITE_APP_MODE=calculator vite build",
     "build:website": "VITE_APP_MODE=website vite build",
     "build-with-types": "tsc --noEmit && vite build",
     "preview": "vite preview",
     "typecheck": "tsc --noEmit",
-    "lint": "npm run eslint && npm run stylelint",
+    "lint": "bun run eslint && bun run stylelint",
     "eslint": "eslint . --cache",
     "stylelint": "stylelint '**/*.css' --cache",
     "prettier": "prettier --check \"**/*.{ts,tsx}\"",
     "prettier:write": "prettier --write \"**/*.{ts,tsx}\"",
     "vitest": "vitest run",
     "vitest:watch": "vitest",
-    "test-all": "npm run prettier && npm run eslint && npm run typecheck && npm run vitest && npm run build",
-    "test": "npm run vitest",
-    "test:quick": "npm run vitest",
+    "test-all": "bun run prettier && bun run eslint && bun run typecheck && bun run vitest && bun run build",
+    "test": "bun run vitest",
+    "test:quick": "bun run vitest",
     "storybook": "storybook dev -p 6006",
     "storybook:build": "storybook build"
   },

app/src/tests/unit/hooks/useCreateHousehold.test.tsx

@@ -89,8 +89,9 @@ describe('useCreateHousehold', () => {
         expect(result.current.isPending).toBe(false);
       });
 
-      // Verify API calls
-      expect(mockCreateHousehold).toHaveBeenCalledWith(mockHouseholdCreationPayload);
+      // Verify API calls (check only first argument, as React Query may pass additional context)
+      expect(mockCreateHousehold).toHaveBeenCalled();
+      expect(mockCreateHousehold.mock.calls[0][0]).toEqual(mockHouseholdCreationPayload);
       expect(mockCreateHouseholdAssociationMutateAsync).toHaveBeenCalledWith({
         userId: TEST_IDS.USER_ID,
         householdId: TEST_IDS.HOUSEHOLD_ID,
@@ -177,8 +178,9 @@ describe('useCreateHousehold', () => {
         associationError
       );
 
-      // Household creation should succeed
-      expect(mockCreateHousehold).toHaveBeenCalledWith(mockHouseholdCreationPayload);
+      // Household creation should succeed (check only first argument)
+      expect(mockCreateHousehold).toHaveBeenCalled();
+      expect(mockCreateHousehold.mock.calls[0][0]).toEqual(mockHouseholdCreationPayload);
     });
   });