diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..3a43b1c
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
+jobs:
+  build:
+    name: Build & test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '21'
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Build & test
+        run: ./gradlew build --no-daemon
diff --git a/README.md b/README.md
index e0f1e5d..ced1577 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,7 @@
 # Program analysis for your coding agents.
 
+[![CI](https://github.com/blindhacker99/code-reason/actions/workflows/ci.yml/badge.svg)](https://github.com/blindhacker99/code-reason/actions/workflows/ci.yml)
+
 **code-reason** is an MCP server that gives coding agents real program-analysis reasoning — so they verify data flow, trace evidence chains, and navigate call graphs from ground truth, not guesswork.
 
 Coding agents are good at reading code, but they struggle with whole-program questions: