pgBackRest aims to be a simple, reliable backup and restore system that can seamlessly scale up to the largest databases and workloads.

migra is a schema comparison tool for PostgreSQL.

It's a command line tool, and Python library. Find differences in database schemas as easily as running a diff on two text files.

Migra makes schema changes almost automatic. Management of database migration deployments becomes much easier, faster, and more reliable.

PostgreSQL schema documentation tool

Prisma turns your database into a powerful GraphQL API which you can either use to build your own GraphQL server or connect to it directly from the frontend.

repmgr is an open-source tool suite for managing replication and failover in a cluster of PostgreSQL servers. It enhances PostgreSQL's built-in hot-standby capabilities with tools to set up standby servers, monitor replication, and perform administrative tasks such as failover or manual switchover operations.

Metabase is the easy, open source way for everyone in your company to ask questions and learn from data.

Client-Side Database for Browsers, NodeJS, electron, cordova, react-native and every other javascript-runtime

Scuttlebot is an open source peer-to-peer log store used as a database, identity provider, and messaging system. It has:

Global replication
File-synchronization
End-to-end encryption

The Postgresql object model manager for PHP

Pomm is an open source database access framework coupled with an Object Model Manager dedicated to the Postgresql™ database. It offers an alternative approach than ORM to using database in web developments.

A fast, in-memory document-oriented datastore for node.js, browser and cordova

RethinkDB is the first open-source, scalable JSON database built from the ground up for the realtime web. It inverts the traditional database architecture by exposing an exciting new access model – instead of polling for changes, the developer can tell RethinkDB to continuously push updated query results to applications in realtime. RethinkDB’s realtime push architecture dramatically reduces the time and effort necessary to build scalable realtime apps.

VersionPress is a free and open source version control plugin for WordPress built on Git. You can:

Undo changes
Create staging sites
Merge databases  ← yes, really!

Simply update your sites with confidence.

Kinto is a lightweight JSON storage service with synchronisation and sharing abilities.

ZeroDB enables clients to run queries over encrypted databases without exposing decrypted data to the server and without a proxy gateway.

PouchDB is an open-source JavaScript database inspired by Apache CouchDB that is designed to run well within the browser.

PouchDB was created to help web developers build applications that work as well offline as they do online.

It enables applications to store data locally while offline, then synchronize it with CouchDB and compatible servers when the application is back online, keeping the user's data in sync no matter where they next login.

Query Editor: think of JS Fiddle for SQL queries. It's your way to share data in the organization in an open way, by sharing both the dataset and the query that generated it.
Visualizations: once you have a dataset, you can create different visualizations out of it.
Dashboards: combine several visualizations into a single dashboard.

WordNet® is a large lexical database of English. Nouns, verbs, adjectives and adverbs are grouped into sets of cognitive synonyms (synsets), each expressing a distinct concept. Synsets are interlinked by means of conceptual-semantic and lexical relations. The resulting network of meaningfully related words and concepts can be navigated with the browser. WordNet is also freely and publicly available for download. WordNet's structure makes it a useful tool for computational linguistics and natural language processing.

ConceptNet is a semantic network containing lots of things computers should know about the world, especially when understanding text written by people.

It is built from nodes representing words or short phrases of natural language, and labeled relationships between them. (We call the nodes "concepts" for tradition, but they'd be better known as "terms".) These are the kinds of relationships computers need to know to search for information better, answer questions, and understand people's goals.

3T MongoChef, the GUI for MongoDB, lets you edit any MongoDB data type directly in a tree-view, table-view or as free JSON text. Visually add documents, fields and values of any MongoDB type with just a stroke of a key – anywhere in your document!

Apache CouchDB™ is a database
that uses JSON for documents,
JavaScript for MapReduce indexes,
and regular HTTP for its API