Didn’t say this in the video, but double and triple check your solder joints! Use a multimeter to test continuity if you are unsure, and use magnification if you can.
Here's a condensed text version if you don't want to sit through the whole video: https://docs.google.com/document/d/1LyNhuZHmpUGp02B4Ra5rUPMFA_zJnd788om9KQ7HWcM/edit?usp=drivesdk
Here are the relevant resources mentioned in the video:
Modular Addict for PCB, etc: https://modularaddict.com/
Mouser Cart: https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=af61ab383e
Thonk for Knobs, etc: https://www.thonk.co.uk/
Building Vagrant development environment: https://github.com/pichenettes/mutable-dev-environment
Muff Wiggler thread: https://www.muffwiggler.com/forum/viewtopic.php?t=143166&highlight=
Drag Soldering: https://www.youtube.com/watch?v=wUyetZ5RtPs
TS-100 soldering iron: https://www.amazon.com/UY-CHAN-Programmable-Pocket-size-Acceleration/dp/B01MDTO6X7
STM32F0 Discovery: https://www.mouser.com/ProductDetail/STMicroelectronics/STM32F0DISCOVERY?qs=y%252bFWVGuMvwZK8miFvhZefg%3D%3D
More Mutable Instruments DIY info: https://www.amazingsynth.com/pcb-info/
One day I might have a charismatic camera presence, but today is not that day. Hopefully this was a useful video anyways.