Databases for Coordination

The original coordination service: hierarchical znodes, watches and ephemeral nodes for clusters.

The key-value store built into HashiCorp Consul for service config, locks and discovery.

Raft-based, strongly consistent key-value store that holds Kubernetes' cluster state.

Fast pure-Java SQL engine for embedded, in-memory and test databases, with compatibility modes.

Pure-Python document store that keeps every table in one human-readable JSON file.

Cheap, schemaless key-attribute store inside an Azure Storage account.

Tiny type-safe local JSON database for Node, Electron and the browser using plain JavaScript.

MySQL-compatible SQL database you can branch, diff, merge and clone like a Git repository.

AWS's original 2007 schemaless attribute store; still running but frozen in time.

Lightweight distributed database that replicates SQLite over Raft behind a simple HTTP API.

Version-controlled SQL database with PostgreSQL compatibility: branch, diff and merge your tables.

Vercel's globally replicated read-optimized config store (renamed Global Config in 2026).

etcd's maintained fork of BoltDB: a simple, pure-Go B+tree store in a single file.

Serverless single-file NoSQL document database for .NET, in the spirit of SQLite.

Canonical's embeddable C library that makes SQLite highly available with Raft replication.

Tencent's mmap-backed key-value store for mobile apps, built as a faster SharedPreferences/NSUserDefaults.

Globally cached, eventually consistent key-value store for read-heavy data at Cloudflare's edge.

Embedded, transactional key-value and JSON document engine in a single C file, with Jx9 scripting.

D. J. Bernstein's constant database: immutable on-disk hash tables with two-read lookups and atomic swaps.

Embedded BSON document database for Rust with a MongoDB-like API and optional wire-protocol server.

Embedded NoSQL document store for Java and Android with pluggable MVStore or RocksDB storage.

Structured static database for game data: spreadsheet-style editor, typed sheets and diff-friendly JSON.

Tiny embeddable C string key-value database from the radare2 project, built on djb's cdb format.

Hosted key-value store driven by plain HTTP calls, with scoped access tokens, TTLs and Lua bucket scripts.

Single-file encrypted key-value store for secrets, with GPG or AES-256 and S3/SSH/gist sync.

Memory-mapped constant database: a faster, thread-safe, >4 GB rewrite of D. J. Bernstein's cdb.

The in-process SQL engine that ships in every phone, browser and OS: one file, zero servers.

Lightweight pure-Dart key-value store for Flutter; development continues in the Hive CE fork.

Serverless SQLite for Cloudflare Workers, priced per row read and written, with read replicas and time travel.

Embeddable JSON document database in C, with a JQL query language and optional HTTP/WebSocket server.