bijou64 is a variable-length integer (varint) encoding developed for a CRDT sync protocol, designed to be canonical by construction — meaning each integer has exactly one valid byte representation, eliminating a class of signature-verification bugs without runtime canonicality checks. Unlike LEB128, which uses continuation bits and allows multiple encodings for the same value, bijou64 uses a first-byte tag to signal total length and applies offsets to guarantee uniqueness. Benchmarks on ARM (M2 Pro) and x86 (Zen 5) show bijou64 decodes 2–10x faster than LEB128, largely because the decoder knows the byte count immediately from the first byte, avoids continuation-bit scanning, and works with contiguous big-endian payloads that map well to CPU byte-swap instructions. The library is published on crates.io (dual MIT/Apache-2.0) with a Wasm/JS wrapper available.
