Inigo Quilez releases poster-sized prints with the accompanying shader code on his patreon, very similar to this! Ray-march shaders aren't necessarily obfuscated, although it can sometimes it can appear that way :)

https://www.patreon.com/inigoquilez

(disclaimer: not affiliated, just a fan of his work)

me too me too ! here is another pointer to his articles: http://www.iquilezles.org/www/index.htm

I bet similarly shaped C code of similar size could render the same image in less than a second :)

Probably, I wonder what code they use for this: https://www.youtube.com/watch?v=hS9nj1vvbTg because deeper zoom requires much higher precision math which takes a lot more computation.

PS: Not as far but much better video: https://www.youtube.com/watch?v=0jGaio87u3A

Such cynicism in the video description update, and comments disabled. Sad to see that happen to such awesome hobby of deep zooming fractals :(

About the code: I don't know about the specific techniques they use, but in general some type of arbitrary precision math is likely used, where you represent numbers with a variable amount of bytes with more bits for higher precision, and using optimized multiplication algorithms that use less than O(n^2) time with n the amount of bits of the numbers

Someone in the comments posted a C version that's 16 times faster, but it's 27 lines long instead of 21.