Think first about what you want to build. Deeply engage with the domain. If you want to appeal to windsurfing geeks, become a windsurfing geek, and build an app that is useful to them... then, figure out what kinds of technological wizardry will help you accomplish that vision. Domain first, content first, product first... never technical exploration for technical exploration or learning sake.
This is a schematic for process that can be used with Agile development, or any other methodology, and details some of the basic "artifacts" (meaning essentially shared work products, things saved to disk, things emailed, posted in slack, uploaded to basecamp/jira/confluence ...etc) that are pre-requisites (or co-requisites) for successful front end engineering.
...A problem arises though, when those services are adapted by the providers (usually in some sort of pivot from a more general non-medical service) to provide a HIPAA compliant service. Among it's many requirements, HIPAA states, paraphrasing 'though shalt not share Personally Identifying Health Information' without proper and very controlled, logged access.
OSMI's twitter feed has had a little bit of activity around the subject of burnout in the tech community this week. I did some of my own reading, and found a fascinating article titled "Mining Valence, Arousal, and Dominance -- Possibilities for Detecting Burnout and Productivity?" by Mika Mäntylä et. al.
In "feature-driven" agile development, who is champion-ing for things like security, performance, and maintainability?
I highly recommend the book "Doing Math With Python" by No Starch Press, particularly chapter 7 on Calculus. I hadn't looked at derivatives or integration in a while, and this was a useful review.