diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..9e57955
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,48 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    name: Build and Test
+    runs-on: ubuntu-latest
+
+    env:
+      MIX_ENV: test
+      ELIXIR_VERSION: "1.17.3"
+      OTP_VERSION: "27.2"
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Elixir
+        uses: erlef/setup-beam@v1
+        with:
+          elixir-version: ${{ env.ELIXIR_VERSION }}
+          otp-version: ${{ env.OTP_VERSION }}
+
+      - name: Cache deps
+        uses: actions/cache@v4
+        with:
+          path: |
+            deps
+            _build
+          key: ${{ runner.os }}-mix-${{ env.ELIXIR_VERSION }}-${{ env.OTP_VERSION }}-${{ hashFiles('mix.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-mix-${{ env.ELIXIR_VERSION }}-${{ env.OTP_VERSION }}-
+
+      - name: Install dependencies
+        run: mix deps.get
+
+      - name: Compile
+        run: mix compile --warnings-as-errors
+
+      - name: Run tests
+        run: mix test
diff --git a/test/items_api/migration_test.exs b/test/items_api/migration_test.exs
new file mode 100644
index 0000000..6ea8721
--- /dev/null
+++ b/test/items_api/migration_test.exs
@@ -0,0 +1,38 @@
+defmodule ItemsApi.MigrationTest do
+  use ExUnit.Case, async: false
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(ItemsApi.Repo)
+    :ok
+  end
+
+  describe "auto-migration on startup" do
+    test "items table exists after application start" do
+      # The application has already started (mix test starts it via mod:),
+      # so migrations should have run. Verify the items table exists.
+      {:ok, %{rows: tables}} =
+        Ecto.Adapters.SQL.query(ItemsApi.Repo, "SELECT name FROM sqlite_master WHERE type='table' AND name='items'")
+
+      assert tables == [["items"]]
+    end
+
+    test "items table has expected columns" do
+      {:ok, %{rows: columns}} =
+        Ecto.Adapters.SQL.query(ItemsApi.Repo, "PRAGMA table_info(items)")
+
+      column_names = Enum.map(columns, fn [_cid, name | _rest] -> name end)
+      assert "id" in column_names
+      assert "name" in column_names
+      assert "description" in column_names
+      assert "inserted_at" in column_names
+    end
+
+    test "re-running migrations is idempotent" do
+      migrations_path = Application.app_dir(:items_api, "priv/repo/migrations")
+      # Running migrations again should not crash
+      result = Ecto.Migrator.run(ItemsApi.Repo, migrations_path, :up, all: true)
+      # Returns empty list when all migrations already applied
+      assert result == []
+    end
+  end
+end