Directory

Distributed event streaming platform with durable, partitioned, replayable logs, Kafka Connect connectors and Kafka Streams processing

Open-source password manager with hosted and self-hosted server options, passkey support, organization sharing and a separate Secrets Manager for developers

Open-source columnar OLAP database server for fast aggregations over billions of rows, with MergeTree storage, SQL and a managed ClickHouse Cloud

In-process analytical SQL database that queries Parquet, CSV and Arrow data directly from Python, R, Node or the CLI

Distributed search and analytics engine on Apache Lucene with full-text, aggregations, vector search and ES|QL; triple-licensed AGPL, SSPL and Elastic License

Secrets, certificate and privileged-access management platform with an MIT-licensed core, available as a hosted service or self-hosted deployment

Open-source LLM observability and evaluation platform: tracing, LLM-as-judge and human evals, prompt management, datasets and cost dashboards, self-hostable or as Langfuse Cloud

Open-source vector-tile map renderers for web (GL JS) and native platforms, forked from Mapbox GL and governed by a community organisation

Rust search engine for application search-as-you-type with typo tolerance, faceting and hybrid semantic search; MIT core plus BSL enterprise parts

Open-source vector database from Zilliz with Lite, Standalone and Distributed deployments, many index types and GPU acceleration

Open JSON-RPC standard for connecting AI applications to tools, data and prompts through servers, now stewarded under the Linux Foundation with SDKs in many languages

Open-source runtime and model manager for running open-weight LLMs locally on macOS, Windows and Linux, with a REST API, OpenAI- and Anthropic-compatible endpoints and optional cloud models

Apache-2.0 search and analytics suite forked from Elasticsearch and Kibana, governed by the OpenSearch Software Foundation

Microsoft's browser automation and end-to-end testing framework driving Chromium, Firefox and WebKit from one API in TypeScript, Python, Java and .NET

Open-source vector search engine written in Rust with filterable HNSW indexes, sparse and multi-vector support, REST/gRPC APIs and a managed cloud

Open-source backend platform built around a dedicated PostgreSQL database with auto-generated APIs, authentication, file storage, realtime subscriptions and edge functions

GPL-licensed in-memory search engine in C++ offering typo-tolerant instant search, faceting, vector and hybrid search, with Typesense Cloud hosting

Open-source vector database in Go with pluggable vectorizer modules, hybrid BM25 and vector search, multi-tenancy and a managed cloud