diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..6f429b1
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,9 @@
+# Build mobile — environment variables
+# Copy to .env.local for local overrides (never commit .env.local)
+
+# API endpoints (defaults to production; override for local dev)
+EXPO_PUBLIC_API_URL=https://build.interactor.com
+EXPO_PUBLIC_ACCOUNT_SERVER_URL=https://auth.interactor.com
+
+# EAS CI token — set in GitHub Actions secrets, never commit
+# EXPO_ACCESS_TOKEN=eas_...
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..e185550
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,40 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  lint-typecheck:
+    name: Lint & Typecheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm ci
+      - run: npm run lint
+      - run: npm run typecheck
+
+  eas-build-preview:
+    name: EAS Build (preview)
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request'
+    needs: lint-typecheck
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm ci
+      - uses: expo/expo-github-action@v8
+        with:
+          eas-version: latest
+          token: ${{ secrets.EXPO_ACCESS_TOKEN }}
+      - name: Build preview (iOS + Android)
+        run: eas build --platform all --profile preview --non-interactive --no-wait
diff --git a/.gitignore b/.gitignore
index 626da2d..f434da6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,6 +35,10 @@ yarn-error.*
 .env.local
 .env*.local
 
+# EAS credentials (never commit)
+.eas/service-account.json
+EXPO_ACCESS_TOKEN
+
 # typescript
 *.tsbuildinfo
 
diff --git a/app.json b/app.json
index 7809a78..6d7b472 100644
--- a/app.json
+++ b/app.json
@@ -2,6 +2,7 @@
   "expo": {
     "name": "Build",
     "slug": "product-manager-mobile",
+    "owner": "interactor",
     "version": "1.0.0",
     "orientation": "portrait",
     "icon": "./assets/icon.png",
@@ -43,6 +44,12 @@
     ],
     "experiments": {
       "typedRoutes": true
+    },
+    "extra": {
+      "router": {},
+      "eas": {
+        "projectId": "88a146cc-a2b2-48f2-aeea-314c745d4e5a"
+      }
     }
   }
 }
diff --git a/eas.json b/eas.json
new file mode 100644
index 0000000..2f4c679
--- /dev/null
+++ b/eas.json
@@ -0,0 +1,46 @@
+{
+  "cli": {
+    "version": ">= 16.0.0",
+    "appVersionSource": "local"
+  },
+  "build": {
+    "development": {
+      "developmentClient": true,
+      "distribution": "internal",
+      "ios": {
+        "simulator": false
+      },
+      "env": {
+        "EXPO_PUBLIC_API_URL": "https://build.interactor.com",
+        "EXPO_PUBLIC_ACCOUNT_SERVER_URL": "https://auth.interactor.com"
+      }
+    },
+    "preview": {
+      "distribution": "internal",
+      "env": {
+        "EXPO_PUBLIC_API_URL": "https://build.interactor.com",
+        "EXPO_PUBLIC_ACCOUNT_SERVER_URL": "https://auth.interactor.com"
+      }
+    },
+    "production": {
+      "autoIncrement": true,
+      "env": {
+        "EXPO_PUBLIC_API_URL": "https://build.interactor.com",
+        "EXPO_PUBLIC_ACCOUNT_SERVER_URL": "https://auth.interactor.com"
+      }
+    }
+  },
+  "submit": {
+    "production": {
+      "ios": {
+        "appleId": "peter@interactor.com",
+        "ascAppId": "",
+        "appleTeamId": ""
+      },
+      "android": {
+        "serviceAccountKeyPath": ".eas/service-account.json",
+        "track": "internal"
+      }
+    }
+  }
+}