# Setup Welcome to your Mailtrain project on Nitrous. ## Running the development server: In the [Nitrous IDE](https://community.nitrous.io/docs/ide-overview), start Mailtrain via "Run > Start Mailtrain". Now you've got a development server running and can see the output in the Nitrous terminal window. You can open up a new shell or utilize [tmux](https://community.nitrous.io/docs/tmux) to open new shells to run other commands. ## Preview the app In the Nitrous IDE, open the "Preview" menu and click "Port 3000".