Search platforms (non-memory)

Search-as-a-service API for instant search experiences — NeuralSearch (vector) + lexical. Adopted by 12000+ companies including LVMH, Stripe.

Elastic's managed Elasticsearch cloud — vector search (ELSER reranker, dense vectors), full-text, observability, security. Public (NYSE: ESTC).

AWS-led fork of Elasticsearch 7 — Apache-licensed; k-NN plugin, OpenSearch ML, neural-search. Substrate beneath AWS OpenSearch Service.

Open-source Postgres extension for vector similarity — HNSW and IVFFlat indexes; widely deployed (Supabase, Neon, AWS RDS, Crunchy, Azure).

Hosted managed Qdrant cloud — multi-cloud single-tenant clusters; hybrid cloud private deployment; widely used as a memory backend (Mem0 default).

Supabase's managed pgvector — combined Postgres + vector store; popular default for OSS LLM apps. Supabase $80M Series C 2024.

Hosted Vespa.ai (originally Yahoo internal). Hybrid search + ML inference at billions-of-documents scale. Used by Spotify, OkCupid, Wix.

Managed cloud SaaS for Weaviate — serverless or dedicated; multi-cloud (AWS/GCP/Azure); enterprise hybrid deployment.

Commercial managed cloud for Milvus — multi-cloud (AWS/GCP/Azure); enterprise tier with private deployment.

French open-source search engine — fast, typo-tolerant, vector search beta. Meilisearch Cloud commercial.

Open-source distributed search engine for logs/traces — cloud-native (object storage as primary tier). Acquired by Datadog 2024.

Rust port of Lucene — embedded full-text search engine. Underlies Quickwit, Lnx, Bayard. Used in Meilisearch and many in-process search engines.

Open-source search engine focused on typo-tolerance and ease of use — Typesense Cloud commercial; rising Algolia alternative.

Site-search platform (formerly Sajari) — vector and lexical search for e-commerce / content sites. Smaller player vs Algolia/Coveo.

Yahoo Japan's open-source distributed vector search engine — built on NGT; Kubernetes-native; horizontal scaling.