You know, I wanted to do something very similar with my university's installation of PeopleSoft - but my intent was more focus on improving the UI and frontend than backend. But I have to ask: how did you get a copy of PeopleSoft?
Actually, what I'm working on involves both front-end and back-end. I've got a UI that trades data back and forth with a web service endpoint called Integration Broker within PeopleSoft. I'm focused on enrollment right now, and currently I've got a system that allows me to enroll in classes using the new UI on a live PeopleSoft install - all without touching/modifying the business logic in the delivered vanilla PeopleSoft implementation.
Re. the PeopleSoft copy - Oracle provides all of their software (and master license codes) for download for evaluation purposes through a portal called eDelivery. I had to read a few hundred pages of documentation, but after a month I was able to get all the components to talk together. I'm trying to convince Oracle to give me a non-support license so I can cover myself legally, but I'm getting the silent treatment since it's just me and I don't have the budget of a CTO lol.
