Library / SDK
Retrieval & Memory
Annoy
1Memory-mapped 2approximate 3nearest 4neighbors 5from 6Spotify
the six Ws · specification
W1
Who
Maintained by Spotify.
W2
What
Memory-mapped approximate nearest-neighbor search for vectors.
W3
Where
An embedded library in C++ and Python.
W4
When
When you need lightweight, read-only vector indexes.
W5
Why
Tiny, fast indexes that share memory across processes.
W6
With
Your vectors and a supported binding.
W7
Watch
Company-maintained (Spotify); open-source (Apache-2.0), library only. Runs embedded; data stays on your machine.