citadeldb-vector vs veks-io vs nidus

VECTOR(N) type and filtered ANN index for Citadel encrypted database

Standalone vector data I/O — read and write fvec, ivec, mvec, dvec, bvec, svec, npy, parquet, and slab formats

A small, pure-Rust embeddable vector store: brute-force cosine search over a single append-only file. No FFI, no C, no SQL; anyhow its only dependency.