I had Opus 5.5 (Extra) build a Mandelbrot explorer + Conways Game of Life that dives to 10^300 in the browser, and it's one HTML file [2-min demo]

The 2-minute demo is attached. It starts at the whole set, dives to 10^300 on a spiral, zooms in on various fractals, then turns the fractal into Conway's Game of Life. How it came together It started with research, not code. I dug through how the best open-source deep-zoom explorers solve the core problem: normal floating point falls apart around 10^15 zoom. Most of the strongest projects land on the same answer. Compute one reference orbit in arbitrary precision, then have the GPU track each pixel's tiny offset from it. I built on that, plus a couple of newer techniques from the fractal community for avoiding glitches and skipping thousands of iterations at a time. The build is a single file with no libraries, running on WebGL2. The high-precision math runs in a background worker so the UI never freezes. Everything else happens on the GPU. Color is computed separately from the math, so palettes, lighting and color cycling change instantly without re-rendering. Then came verification, which was the part I cared most about. I compared the output against independent high-precision renders at 10^11, 10^31 and 10^300. Agreement on what's inside versus outside the set came in at 99.7–100%, and side-by-side images were indistinguishable. Fun finding: the few "wrong" pixels weren't bugs. In those regions the true answer changes by dozens of iterations if you move a hundred-thousandth of a pixel. Optimization came next, profile first and then fix. The changes that made the biggest difference: skipping regions provably inside the set sizing GPU work to real measured timings snapping the reference point onto nearby mini-Mandelbrots, so its orbit only needs one cycle a progressive half-res pass that never computes a pixel twice Overall it's about 2.4× faster than the first working version, and up to 5.5× on interior-heavy views, with no loss in image quality. One of my "optimizations" actually made things 3× slower. Benchmarking caught it before it shipped. The last stretch was polish: autopilot that steers itself toward detail, hand-tuned palettes, relief lighting, and the Game of Life mode. What's next: getting this to scale. A website so you can try this yourself (I could use some help on this)! More on that soon. Try with the Claude link: https://claude.ai/artifact/65DhaH5Kice4D2A6EMeCoC