GraphQL Code Generator
Generates typed clients, resolvers and SDKs from a GraphQL schema
155 tools in our directory are marked as best for Backend teams, from 22 sections: Databases (25), APIs (21), Frameworks (16), Testing & QA (15) and 18 more sections.

Generates typed clients, resolvers and SDKs from a GraphQL schema

Open source high performance RPC framework using Protocol Buffers

Instant GraphQL API for your databases, with built-in access rules

Open source engine for background tasks, workflows and AI agents

Event-based tracing and debugging for production systems

Reliable receiving, routing and sending of webhooks and events

Library for getting structured, validated data from LLM output

Java and Kotlin IDE with code intelligence and built-in tools

Open source service mesh for traffic, security and observability

Open source distributed tracing for microservice performance issues

Open source automation server for building, testing and deploying

Schema description and validation library for JavaScript objects


Programmer-friendly testing framework for Java and the JVM

Open source serverless platform for containers on Kubernetes

SQL query builder for JavaScript with many database dialects

Open source API gateway for securing and managing API traffic

Kotlin test framework with assertions and property testing


Open source API gateway that aggregates, transforms and secures APIs

Type-safe SQL query builder for TypeScript with zero dependencies

Frameworks and a platform for building and monitoring AI agents

Low-level framework for stateful, long-running agents as graphs


Local SMTP server and web inbox for testing outgoing email


Self-hosted team chat for private, secure workplace messaging



Open source mock, proxy and recording server for HTTP and gRPC

Widely used open source SQL database for web and business apps


Open source game backend for multiplayer and social games

TypeScript framework for structured, scalable Node.js server apps


Open source JavaScript runtime for servers and command line tools

Platform for running containers, jobs, databases and sandboxes


Isolated test environments on Kubernetes for AI coding agents

General-purpose policy engine that decouples policy from code

Lightweight Python SDK for agents, handoffs and guardrails

Serverless functions that run on any Kubernetes cluster

Open standard and tools for collecting traces, metrics and logs


Go-based open source web application firewall with CRS support

Fast, scalable build system for large multi-language codebases


Lightweight connection pooler for PostgreSQL databases
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