Professionally active as a developer for a year now after graduating from engineer school, I can offer you app development. I'm mostly a back-end developer. My stack is Ruby On Rails, node.JS(express,...). But I'm quite good at front-end too. I can use javascript framework as angular and react. I always follow good practices while coding so my code is readable and maintenable. For testing purpose, I code unit tests , integration tests and functional tests in order to avoid at max regression. I have basic skills in devops so deploying ain't a problem at all, I can even make a functional CI/CD for you to ease delivery and testing.