diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f313d03..8ececc2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,6 +44,21 @@ jobs:
       - name: Ruff format check
         run: uv run ruff format --check .
 
+  ui:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@d23441a48e516b6c34aea4fa41551a30e30af803 # v6.1.0
+
+      - uses: actions/setup-node@249970729cb0ef3589644e2896645e5dc5ba9c38 # v6.5.0
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: ui/package-lock.json
+
+      # tsc -b && vite build, same as the release workflow bundles.
+      - name: Build UI
+        run: make build-ui
+
   test:
     runs-on: ubuntu-latest
     strategy: