Isaac Breen

Software · research · writing

I like making difficult machinery disappear.

I build software around parsing, structured generation, and machine learning—usually with an eye on the part of the system that becomes expensive, awkward, or hard to reason about.

GLRMask

Grammar-constrained decoding, with most of the hard work moved out of generation.

A Rust and Python library for JSON Schema and general context-free grammars. GLRMask compiles lexer, parser, and tokenizer interactions into weighted automata so the runtime can produce the next-token mask from the current parse state.

Active project
Rust · Python · parsing
GLRMask Open project site →