These are the steps that happen when you deploy the application.
1. Push to `master` branch, or merge in a pull request to the `master` branch.
2. This triggers a build on [Travis CI](https://travis-ci.org/processing/p5.js-web-editor).
3. Travis CI builds a (development) Docker image of the whole application.
4. Travis CI runs some tests, which in this case, is just `npm run lint`. This could be updated in the future to include more extensive tests. If the tests fail, the build stops here.
5. If the tests pass, then Travis CI builds a (production) Docker image of the whole application.
6. This image is pushed to [Docker Hub](https://hub.docker.com/r/catarak/p5.js-web-editor/) with a unique tag name (the Travis commit) and also to the `latest` tag.
8. Since production assumes your environment variables are in the shell environment, and not in a `.env` file, you will have to run `export $(grep -v '^#' .env | xargs)` or a similar command, see this [Stack Overflow answer](https://stackoverflow.com/a/20909045/4086967).
If you are interested in hosting and deploying your own p5.js Web Editor instance, you can! It would be the same as the official editor instance at editor.p5js.org, except with a different domain, and you would be in charge of the maintenance. We recommend using Heroku as you can host it for free.