Getting Started with App Available Scripts In the project directory, you can run: yarn start Runs the app in the development mode. Environment Variables REACT_APP_SPONSOR_API_KEY= REACT_APP_SPONSOR_API_KEY_MAINNET= REACT_APP_GNOSIS_RPC_URL= REACT_APP_MUMBAI_RPC_URL= REACT_APP_BASEGOERLI_RPC_URL=