diff --git a/.circleci/config.yml b/.circleci/config.yml
index 6229170..a3a8ba2 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -2,30 +2,41 @@
 # See: https://circleci.com/docs/configuration-reference
 version: 2.1
 
-# Define a job to be invoked later in a workflow.
-# See: https://circleci.com/docs/jobs-steps/#jobs-overview & https://circleci.com/docs/configuration-reference/#jobs
+orbs:
+  node: circleci/node@6
+
 jobs:
-  say-hello:
-    # Specify the execution environment. You can specify an image from Docker Hub or use one of our convenience images from CircleCI's Developer Hub.
-    # See: https://circleci.com/docs/executor-intro/ & https://circleci.com/docs/configuration-reference/#executor-job
+  validate-config:
     docker:
-      # Specify the version you desire here
-      # See: https://circleci.com/developer/images/image/cimg/base
-      - image: cimg/base:current
+      - image: cimg/base:stable
+    steps:
+      - checkout
+      - run:
+          name: Validate CircleCI configuration syntax
+          command: |
+            curl -fLSs https://raw.githubusercontent.com/CircleCI-Public/circleci-cli/main/install.sh | bash -s -- --no-sudo --install-dir /tmp/circleci-cli
+            /tmp/circleci-cli/circleci config validate .circleci/config.yml
 
-    # Add steps to the job
-    # See: https://circleci.com/docs/jobs-steps/#steps-overview & https://circleci.com/docs/configuration-reference/#steps
+  build:
+    docker:
+      - image: cimg/node:22.19
     steps:
-      # Checkout the code as the first step.
       - checkout
       - run:
-          name: "Say hello"
-          command: "echo Hello, World!"
+          name: Install dependencies
+          command: npm ci --legacy-peer-deps
+          working_directory: aq-dashboard
+      - run:
+          name: Build
+          command: npm run build
+          working_directory: aq-dashboard
+      - run:
+          name: Test
+          command: npm test -- --watchAll=false --passWithNoTests
+          working_directory: aq-dashboard
 
-# Orchestrate jobs using workflows
-# See: https://circleci.com/docs/workflows/ & https://circleci.com/docs/configuration-reference/#workflows
 workflows:
-  say-hello-workflow: # This is the name of the workflow, feel free to change it to better match your workflow.
-    # Inside the workflow, you define the jobs you want to run.
+  build-workflow:
     jobs:
-      - say-hello
\ No newline at end of file
+      - validate-config
+      - build
diff --git a/aq-dashboard/src/App.test.tsx b/aq-dashboard/src/App.test.tsx
new file mode 100644
index 0000000..582a875
--- /dev/null
+++ b/aq-dashboard/src/App.test.tsx
@@ -0,0 +1,41 @@
+import React from 'react';
+import { render, screen } from '@testing-library/react';
+import App from './App';
+
+// Stub geolocation so Dashboard does not throw in jsdom
+beforeEach(() => {
+  Object.defineProperty(global.navigator, 'geolocation', {
+    configurable: true,
+    value: {
+      getCurrentPosition: jest.fn(),
+    },
+  });
+});
+
+// Stub leaflet, which relies on a browser DOM unavailable in jsdom
+jest.mock('react-leaflet', () => ({
+  MapContainer: ({ children }: { children: React.ReactNode }) => (
+    <div data-testid="map-container">{children}</div>
+  ),
+  TileLayer: () => <div data-testid="tile-layer" />,
+}));
+
+jest.mock('axios');
+
+describe('App', () => {
+  it('renders without crashing', () => {
+    render(<App />);
+  });
+
+  it('shows the waiting-for-location prompt while geolocation is pending', () => {
+    render(<App />);
+    expect(screen.getByText(/waiting for location/i)).toBeInTheDocument();
+  });
+
+  it('shows a button to enter location manually', () => {
+    render(<App />);
+    expect(
+      screen.getByRole('button', { name: /enter location manually/i })
+    ).toBeInTheDocument();
+  });
+});
diff --git a/aq-dashboard/src/index.tsx b/aq-dashboard/src/index.tsx
index 0ee8b59..8724060 100644
--- a/aq-dashboard/src/index.tsx
+++ b/aq-dashboard/src/index.tsx
@@ -1,6 +1,5 @@
 import { createRoot } from 'react-dom/client';
 import React from 'react';
-import ReactDOM from 'react-dom/client';
 import './index.css';
 import App from './App';
 import reportWebVitals from './reportWebVitals';