Introducing GLSL Captcha.
Pass the test by guessing the correct output for the GLSL shader code:
glsl-captcha.vercel.app

Beginner Tuts:
Common Mistakes: mini.gmshaders.com/p/mistakes
Texels and Pixels: mini.gmshaders.com/p/gm-shaders...
Texture Pages: mini.gmshaders.com/p/gm-shaders...
Shader Limits: mini.gmshaders.com/p/limits
Scaling/Ratios: mini.gmshaders.com/p/gm-shaders...
Visual Dev: mini.gmshaders.com/p/visdev

Here are some interesting tricks I've picked up through code golfing:
Using sine waves for rounded cubes in raymarchers

length(sin(p)-.7)-.5

every day I log on and people try their best to get me to lose my faith in humanity. but I am resilient and have a bad memory

Using Play Integrity API is an incredibly anti-privacy and anti-security practice despite being wrongly portrayed as a security feature. The notification will include a link for leaving a rating and review for the app via sandboxed Play Store to make it very convenient for people to send complaints.

absolutnie nie obchodzi mnie to że rafał trz*skowski i donald t*sk sobie założyli konto

re-upping this, my most favourite of the public feeds:

bsky.app/profile/did:...

basically, it just gives you random posts from the people you follow in the last 24 or so hours, because you're bound to miss some of it.
It's my most used feed aside from the main one