An Online School System
Instead of going with a separate repo for each frontend apps, this repo with different branches for the build artifacts at the root level approach is followed as anyway at a time single frontend app will remain deployed. For instance Angular app branch is ghpage with it's own gitignore file for local only files to be ignored.
The backend-spring app is configured with heroku-maven-plugin for uploading the JAR file directly to Heroku and specifying the command for Heroku to run the JAR file. Reference: https://devcenter.heroku.com/articles/deploying-java-applications-with-the-heroku-maven-plugin for details. However this is not a scalable approach as it uploads 70MB+ JAR file everytime. So the Spring backend app in this repo is not maintained anymore, kept here only for reference to heroku-maven-plugin. It is now in https://github.com/coderperfect/prodemics-backend-spring for deployment with the code directly to Heroku taking advantage of the Heroku detection of Spring boot app and doing both creation of JAR file and running it by passing the port in the java -jar command which needs to be passed in the JAR deployment heroku-maven-plugin approach.