He push and work on the implementation of Rust [1] and WebAssembly [2] to the tool.

[1] https://medium.com/figma-design/rust-in-production-at-figma-...

[2] https://medium.com/figma-design/webassembly-cut-figmas-load-...

As well as esbuild. I wonder what he's doing these days since he stepped out of Figma.

My Rust CAD library is based on his CSG.js: https://github.com/timschmidt/csgrs