FAWK: LLMs can write a language interpreter

A developer used Claude Sonnet 4.5 to create FAWK, a functional programming-inspired variant of AWK with first-class arrays, lambdas, lexical scope, and immutability. The LLM successfully generated a working interpreter in Python within a day, including comprehensive tests and backwards compatibility with GAWK. The project demonstrates how modern LLMs can handle complex programming language implementation tasks, though it raises questions about code ownership and maintainability when developers don't write the code themselves.