So I was recently very attracted to some no-code platforms because I have a simple cloud based application that interacts with some APIs, authenticating with OA

So I was recently very attracted to some no-code platforms because I have a simple cloud based application that interacts with some APIs, authenticating with OAuth2. I know what I want to do, but as a primarily systems developer with very limited web development, I have no interest or desire to start creating websites to perform user authentication (not least when I only have one user), along with storing credentials securely, running a server etc etc. It feels to me that some service should exist that provides the API plumbing I need so I can just write the code that processes data and writes to APIs. Things like zapier can probably do it, but then it becomes a hassle to add arbitrary code to the mix. Does anyone know of anything that can help here?