> For the complete documentation index, see [llms.txt](https://docs.vea.ninja/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vea.ninja/build-xchain-dapps/lightbulb-demo.md).

# Lightbulb Demo

The lightbulb [demo](https://lightbulb-vea.vercel.app/) demonstrates a simple dapp integrated with Vea. The switch lives on Arbitrum Sepolia and the Lightbulb lives on a different chain, either Chiado or Sepolia, and they communicate with Vea.

[Try it out](https://lightbulb-vea.vercel.app/)!

## User flow

### 1. Hit The Switch (Arbitrum Sepolia)

<figure><img src="/files/1jaCBSs76BMsXrGZro9q" alt=""><figcaption></figcaption></figure>

### 2. Wait for Vea

<figure><img src="/files/DXWFCqRvrqqYDpULLxNm" alt=""><figcaption></figcaption></figure>

The status of the Vea bridging process and whether your messages have been bridged can be tracked in [VeaScan](https://veascan.io/). You can find the messageId associated with the switch transaction in the event log.

<figure><img src="/files/Xz1Gg6G5QlvGjvM47djN" alt="" width="563"><figcaption><p>Switch Transaction event log</p></figcaption></figure>

When the Vea testnet has bridged your message, you can find your message in a recently bridged 'snapshot'.

<figure><img src="/files/4dz8EmfBLj9tdoSWNR7o" alt="" width="563"><figcaption><p>VeaScan successfully bridged message.</p></figcaption></figure>

### 3. Wait For Relayers

Now that the message to turn on the lightbulb is ready, we can relay it manually, or we can wait for relayers.

## The Final Result

<figure><img src="/files/enUAFweMlXa1AFN7Ms9q" alt=""><figcaption></figcaption></figure>