Espresso

What is it?
Espresso is a tool that lets you use crypto in places where there is no internet, no Wi-Fi, and no cell signal. It allows a user with a inexpensive radio chip (ESP32) to send a "command" (like "Swap my tokens") into space via satellite. That command is then saved on the Bitcoin network and finished on a modern blockchain like Polygon or Sepolia.
How does it work?

1. The Command: You use a small handheld device to sign a trade. Since you have no internet, the device sends this as a Radio Signal (LoRa) to a satellite.
2. The Satellite Relay: The satellite sends your radio signal down to a "Ground Station" that is connected to the internet.
3. The Bitcoin Message Board: The ground station takes your command and "hides" it inside a Bitcoin transaction (using a field called OP_RETURN). Now, your trade command is permanently written on the world's most secure network Bitcoin.
4. The Chainlink Watchman (CRE): Chainlink Runtime (CRE) is the "brain." It constantly watches the Bitcoin network. As soon as it sees your command on Bitcoin, it reads it and uses Chainlink CCIP to go to another blockchain (like Polygon) and actually perform your trade.
   What problem does it solve?

• The Internet Problem: Most crypto apps only work if you have 5G or Wi-Fi. If the power goes out or you are in a remote area, you can't move your money. Espresso fixes this with radio waves.
• The Bitcoin Problem: Bitcoin is very safe, but it can't "talk" to smart contracts or apps like Uniswap. Espresso uses Bitcoin as a secure "bulletin board" where commands can be posted and then read by Chainlink to trigger actions on other chains.

• Handheld Hardware: We used ESP32-LoRa32 microchips. These are low-cost devices that can send data over long distances via radio.
• The Message Hub: We used the Bitcoin Testnet4 network to store the trade commands immutably.
• The "Brain" (Chainlink CRE): We used Chainlink Runtime (CRE) to monitor the Bitcoin blockchain. It acts as the bridge that sees a "dumb" Bitcoin message and turns it into a "smart" cross-chain action.
• The Delivery (Chainlink CCIP): We used CCIP to securely send the final trade instructions to EVM blockchains like Sepolia.