Interview process was excessively long, but not particularly challenging (if you like math and have experience coding). From what I can recall, there was a quick interview over the phone with a current TSE worker at Epic to determine your interest, a personality test to complete, two set of tests to complete (the second including a 3 hr max time limit programming test that can be written in psuedocode (Google that and practice it if you don't know -- not weighted really heavily at all for the interview process, it seems, so just try your best and don't underestimate the time it will take you to complete), a long day of interviews (beginning with a virtual tour/presentation on epic in a small group setting with other interviewees, meeting with a current TSE also with multiple other interviewees (where they describe their current role), proceeding to a one-on-one with a current TSE who asked behavioral-based questions, and finally a one-on-one with an HR hiring manager.
I declined their offer because a question they asked me during the interview pointed towards a problematic company culture... and personally grossed me out. I was not deeply in need of taking this job. I have included it below.
As a person of a non-[white, cisgendered, male] background, it felt like saying to me: tell me what prejudices people, including me, have against you just by looking at you. Now convince me otherwise.