APIs and backends

Workflow automation platform with a self-hostable server and an embeddable builder that a SaaS product can place inside its own app.

Open-source API gateway for routing, securing and managing traffic to APIs, microservices and LLM providers, built on NGINX and etcd.

Java-native API gateway for HTTP, Dubbo, gRPC and WebSocket services, with plugins for authentication, traffic control and observability.

Open-source GraphQL server for Node.js that runs as an add-on to new or existing Node.js apps, including Express, Fastify and AWS Lambda.

Open-source backend platform with authentication, databases, storage, functions and messaging, available as Appwrite Cloud or self-hosted with Docker.

Library of data structures for building collaborative applications, with a JavaScript package and a Rust core.

Dashboard UI for Bull and BullMQ job queues, mounted into an existing Node server or run as a standalone CLI or Docker image.

TypeScript implementation of Connect, a family of libraries for building type-safe APIs from Protocol Buffers schemas.

Open-source platform for building data-driven web applications, with a GraphQL API, PostgreSQL and a React administration interface.

Open-source reactive database and backend for web apps, with server functions written in TypeScript and a cloud platform run by the maker.

Minimalist web framework for Node.js for building web applications and APIs.

TypeScript framework for building server-side Node.js applications, with dependency injection and an Express adapter.

Framework for composing REST, OpenAPI, gRPC, SOAP, database and GraphQL sources into a GraphQL federation supergraph.

A collection of npm packages for building, mocking and stitching GraphQL schemas and resolvers in JavaScript.

Fully-featured GraphQL server library for JavaScript that runs on the WHATWG Fetch API across Node.js and other JavaScript runtimes.

Zero-dependency GraphQL over WebSocket server and client library for JavaScript, with adapters for common WebSocket servers.

JavaScript implementation of the GraphQL specification, providing the parser, validator, executor and type system used to build GraphQL servers, clients and tools.

Open-source GraphQL server that generates a GraphQL API over existing databases and other data sources, with a hosted Hasura Cloud edition.

WebSocket backend for Yjs documents that syncs changes between clients in real time, from the team behind Tiptap.

Self-hosted system for building agents that watch the web and incoming events and take automated actions on the user's behalf.

Workflow orchestration platform for durable functions with step retries, scheduling and flow control, run by applications through language SDKs and self-hostable as a single server.

Open-source backend for web and mobile apps with a client-side, real-time database, auth, permissions, storage and streams.

Open-source orchestration platform for data, AI and infrastructure workflows, defined in YAML and run on a server with a web UI.

Open source API gateway, built on NGINX, that routes, secures and transforms traffic to APIs through plugins, with a Kong Konnect SaaS option.

Go framework for building HTTP and gRPC microservices, with application lifecycle, generated transports, middleware and configuration.

Open-source backend server with a pre-built API, realtime notifications and data storage for web, mobile and IoT applications.

Self-hosted ecommerce platform whose Go backend, GoCommerce, serves the API and an admin panel for a separate SvelteKit storefront.

Workflow automation platform for building AI agents and workflows on a visual canvas, self-hosted or in the cloud.

Messaging server that routes messages between applications and services by subject, with optional persistence through JetStream.

Progressive Node.js framework for building efficient, scalable server-side applications with TypeScript.

TypeScript server toolkit for full-stack servers with filesystem routing, storage, caching and a Vite plugin, deployable to Node.js, Bun, Deno and serverless hosts.

Browser-based flow editor and Node.js runtime for building event-driven applications that connect devices, services and data.

Self-hostable HTTP publish-subscribe server that delivers published messages as push notifications to phones, desktops and browsers.

Open source backend for web and mobile apps that runs on Node.js, stores data in MongoDB or PostgreSQL, and can be mounted on an Express app.

Open-source Go backend shipped as a single executable, with an embedded SQLite database, realtime subscriptions, authentication and a dashboard.

Standalone web server that serves a RESTful API directly from a PostgreSQL database schema.

Python workflow orchestration framework that runs flows on schedules, events or API calls, with a self-hostable server.

Library that enables low-latency, bidirectional and event-based communication between a client and a server.

Self-hosted realtime server written in Rust that serves Pusher-compatible WebSocket and HTTP APIs.

Open source webhook service that sends webhooks with retries, signatures and a customer-facing portal, self-hosted or as a hosted service.

Open-source durable execution platform whose server runs workflows and retries failed steps, self-hosted or as Temporal Cloud.

Open-source platform for building durable AI agents and background tasks in TypeScript, offered as a cloud service and for self-hosting.

Sync engine that keeps a client-side datastore of a web app in step with a Postgres database.