The speaker at the FOSDEM conference in 2023 gave a talk about LNX, a search engine built on top of Tantave, a schema-based search engine library written in Rust. The talk covered the basics of LNX, its features, and its use cases, specifically for user-facing search in e-commerce websites and streaming platforms. The speaker also discussed the challenges of implementing high availability in a distributed system and the importance of eventual consistency. They mentioned the creation of a library called DataCake to simplify the development of distributed systems, including the replication of key-value stores and the use of extensions for additional functionality. The talk concluded with a demo and the suggestion that data sharding is not necessary for most user-facing search applications.