Finna is my own product: a managed search engine for teams that need their data to stay in the EU, with the language handling German actually requires. German compounds its words: a user searching “Straßenbau” needs to find documents about “Straßenbauarbeiten”, and a search engine that does not decompound German misses results a native speaker considers obvious. Finna treats that as a first-class engineering problem, not a plugin.

The engine is written in Rust on Tantivy: full-text search with BM25 ranking, typo tolerance, prefix search, and highlighting, plus bring-your-own vectors for semantic search alongside the keyword index. Architecturally, Finna splits control plane, data plane, and durable storage so each system has one job, fails in its own way, and recovers independently. Load tests put the engine at roughly 290 search requests per second per vCPU, and a design partner is evaluating it on 25 million German-language documents.