GitHub - creationix/rx: RX encoder, decoder, and CLI data tool

REXC is a binary data encoding format and library for JavaScript/TypeScript that serves as a drop-in replacement for JSON.stringify/JSON.parse. It claims 18x smaller output through binary-encoded numbers, de-duplicated strings, and shared schemas, plus 23,000x faster single-key lookup via O(log n) binary search directly on encoded bytes. The library returns a Proxy over a flat byte buffer, enabling near-zero heap allocations. It includes a full CLI tool for converting between JSON and REXC, pretty-printing, and inspecting encoding structure. A low-level cursor API enables zero-allocation traversal for performance-critical paths, and an Inspect API exposes a lazy AST mapping 1:1 to the byte encoding.