Online coding (hackerrank style) with many simple problems. Non-technical phone screen with SWE. Got homework ~3-4+ hours, not programming competition hard but lots of smaller pieces (e.g. build project to this spec). *Horrible* experience with radio silence after that, no feedback, no rejection letter, nothing. If you make people donate 6 hours (including all rounds) of your time for free, have the dignity to send at least one sentence e-mail. I warned people I know at EPFL to avoid Pix4D.