go-covertree is a cover tree implementation in Go for nearest-neighbour search and clustering. It uses an extensible backing store interface (suitable to adapting to key-value stores, RDBMSes, etc) to support very large data sets.

For further horizontal scaling, a partitioned store implementation supports sharding across multiple underlying stores using a partitioning function.

See the API documentation for more details.

This software is made available under an MIT license.

Tree instances are thread-safe for readonly access.

Insertions into the tree (using Insert) are purely append-only operations, and safe to make concurrently, allowing tree construction to be parallelised.

Searching the tree (using FindNearest) is purely a read-only operation and safe to do concurrently, including with insertions.

Removals from the tree (using Remove) are not thread-safe and should be externally synchronised if concurrent read-write access is required.

Store implementations should observe their own thread-safety considerations.