Various search databases and backends as alternatives to Elasticsearch.
- Sonic - github.com/valeriansaliou/sonic - lightweight & schema-less search backend
 - Tantivy - github.com/quickwit-oss/tantivy - full-text search engine library inspired by Apache Lucene
 - Toshi - github.com/toshi-search/Toshi - search engine built on top of Tantivy
 - Bayard - github.com/mosuka/bayard - search engine built on top of Tantivy
 - Meilisearch - github.com/meilisearch/meilisearch - fast and full-featured search engine