SYSTEM Cited by 3 sources
OpenSearch¶
OpenSearch is the Apache-2.0-licensed fork of Elasticsearch + Kibana maintained by the OpenSearch community (originally forked by AWS after Elastic's 2021 license change to SSPL/Elastic License v2). It is a distributed search and analytics engine with a REST API, Lucene-backed indexing, and a Kibana-compatible dashboards component (OpenSearch Dashboards).
How Fly.io uses it¶
Fly.io runs OpenSearch as the permanent-retention
audit trail for token
operations from tkdb — "since virtually all
the operations that happen on our platform are mediated by
Macaroons, this audit trail is itself pretty powerful."
(Source: sources/2025-03-27-flyio-operationalizing-macaroons.)
Distinct from Fly's metrics stack (Prometheus) and tracing stack (Honeycomb + OpenTelemetry) — OpenSearch here serves the forensic-audit use case specifically, where arbitrary ad-hoc queries over history are the primary requirement.
Seen in¶
- sources/2025-03-27-flyio-operationalizing-macaroons — Fly.io's permanent-retention audit trail for token operations.
- sources/2026-01-06-lyft-feature-store-architecture-optimization-and-evolution
— OpenSearch as the embedding-feature store inside Lyft's
dsfeatures. Embedding features require specialised kNN / vector-similarity indexing that DynamoDB doesn't natively provide, so they are split off to OpenSearch while scalar / metadata features stay in DynamoDB + ValKey. Second OpenSearch use-case shape on the wiki: the Fly.io entry above is audit-log / full-text search; Lyft is vector-similarity serving. - sources/2026-03-06-pinterest-unified-context-intent-embeddings-for-scalable-text-to-sql
— OpenSearch as the substrate for Pinterest's internal
Vector Database as a Service.
Multiple teams across Pinterest (Analytics Agent table + query
search, AI Table Documentation, assorted LLM features) run on
one shared OpenSearch-backed platform with Hive as source-of-
truth + Airflow for index creation / ingestion DAGs. Supports
hybrid queries combining vector similarity with metadata filters
("Tier-1 tables semantically similar to
user_actionscontaining impression data"). Third OpenSearch use-case shape on the wiki: multi-tenant internal vector-DB-as-a-service platform — Fly.io = audit log; Lyft = single-team vector feature store; Pinterest = company-wide vector platform.
Related¶
- systems/elasticsearch — the upstream Elasticsearch fork.
- systems/pinterest-vector-db-service
- concepts/audit-trail-in-opensearch
- systems/honeycomb
- systems/opentelemetry