This is an anonymous message posting app called driftbottle. You can find it deployed at https://driftbottle.app
Before starting, you need to install mongodb. On MacOS, this is just:
brew install mongodb-community
In one terminal, start the backend:
cd backend
npm install
npx nodemon .
Now switch to another terminal, and start the frontend dev server:
cd frontend
npm start
This is deployed to heroku automatically whenever a commit is pushed to github at https://github.com/XueYingLin/driftbottle