Crate docbert_plaid 

PLAID-style multi-vector index for docbert.

This crate implements the ColBERT late-interaction indexing pipeline originally described in “PLAID: An Efficient Engine for Late Interaction Retrieval” (Santhanam et al., 2022), modelled on the fast-plaid reference implementation but written directly against plain Rust primitives so that it drops into docbert’s candle-based stack without a libtorch dependency.

The pipeline is built bottom-up over several modules:

• distance — vector distance primitives.
• k-means clustering of token embeddings (next).
• residual codec (coarse centroid + quantized residual).
• inverted file (centroid → documents).
• search path (query tokens → candidate docs → MaxSim).

At the moment the crate only exposes the lowest-level primitives; more layers will be added as subsequent TDD cycles come in.

Re-exports

pub use error::PlaidError;

pub use error::Result;

Modules

codec

Residual quantization codec for PLAID.

device

Device selection for the candle-backed inner loops.

distance

Vector distance primitives used throughout the index.

error

Error type for the PLAID pipeline.

index

Index construction: turn a corpus of token embeddings into a searchable PLAID index.

kmeans

K-means clustering over token embeddings.

persistence

Save and load a built Index to/from disk.

search

Query-time search over a built Index.

update

Incremental updates: mutate an existing Index without retraining.