A developer built Puppy Scheme, a Scheme compiler targeting WebAssembly, in just four days using AI assistance. The project supports 73% of R5RS and R7RS standards and includes features like WASM garbage collection, dead-code elimination, and self-hosting capabilities. The compiler reduced compilation time from 3½ minutes to 11 seconds after AI optimization.

Built as a side project, Puppy Scheme demonstrates how AI tools can accelerate development of complex systems that traditionally took months or years. The compiler generates small binaries through effective dead-code elimination and includes a wasmtime wrapper for creating native executables. A companion website runs Puppy Scheme wasm code on Cloudflare Workers.

The developer created a component model for building interactive web applications using Scheme, with HTML-like syntax and event handling. While still alpha quality with frequent bugs, Puppy Scheme represents a significant achievement in rapid compiler development. The project showcases how AI assistance can help developers explore deep technical challenges in compressed timeframes.