I am a full-time senior dev in an HFT shop. Work is interetsing but fairly intensive.
I have been playing around with a deep learning side project. It is very interesting and rewarding, but will never monetize in a serious way (>US$1M).
A good friend wants me to help him on a less rewarding, but much more monetizatble side project (he already has revenue, users, etc).
Mentally - i have already decided it will be correct life decision to join him. But it is hard to let go of my first "interesting but pointless" project.
I have a nice intersting job and salary. This is just the icing on the cake.
Any hints or suggestions ?