RediSearch supports an extension mechanism, much like Redis supports modules. The API is very minimal at the moment, and it does not yet support dynamic loading of extensions in run-time. Instead, extensions must be written in C and compiled into the engine when building it.
There are two kinds of extension APIs at the moment:
- Query Expanders, whose role is to expand query tokens (i.e. stemmers).
- Scoring Funtions, whose role is to rank search results in query time.