Writing assistant for your second language(s). Right now it’s a web/mobile app but we’re getting ready to launch our browser extension so hopefully that will be more convenient for our users.
Also since the backend is in rust I’ve been contributing to a bunch of the libraries I’m using. There’s definitely been a cost to using rust since a lot of the web dev packages are on the younger side, but the reliability has been huge for a side project. Other than one time I set the wrong send grid API key I don’t think we’ve had a single 500.