Typesense seems like a good fully-featured alternative to Elasticsearch. I.e. it's basically a database with fuzzy-search features (schemas, fields, facets, ordering, scoring profiles, etc), and its speed is enabled by holding everything in RAM.
If you just want the fuzzy-search part (query string -> list of matching document ids) and don't want to pay for GBs of RAM, sonic [1] seems to be an interesting project. It's very fast (μs) and uses very little RAM but doesn't offer DB-like features such as sorting, schemas/fields, scoring etc. It's more of a low-level primitive for building your own search feature than an integrated search db that's ready to use out of the box.
If you just want the fuzzy-search part (query string -> list of matching document ids) and don't want to pay for GBs of RAM, sonic [1] seems to be an interesting project. It's very fast (μs) and uses very little RAM but doesn't offer DB-like features such as sorting, schemas/fields, scoring etc. It's more of a low-level primitive for building your own search feature than an integrated search db that's ready to use out of the box.
[1]: https://github.com/valeriansaliou/sonic