Ask HN: Software developers, what is your side income?

I'm a software developer with nine years of experience. I'm forced to look for extra money because one of my family members requires expensive surgery.

I tried soccer betting in desperation, but I lost a few hundred bucks and decided to close my account.

I started working on creating a programming course that I will post to udemy when I finish.

Could you share tips on how to make a side income as a software developer?