Freemium
Insomnia
Open SourceAPI Clients · API Tools
Open-source API client for REST, GraphQL and gRPC by Kong.
apirestgraphqlgrpc
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API Clients · API Tools
Open-source API client for REST, GraphQL and gRPC by Kong.
Cross-Platform · Mobile Development
Cross-platform SDK using web technologies for hybrid apps.
Orchestration · DevOps
The leading service mesh for traffic, security and observability.
Terminals & Shells · Development Environment
Feature-rich macOS terminal emulator with split panes and search.
APM & Tracing · Monitoring & Observability
Open-source distributed tracing platform, CNCF graduated.
Models & LLM APIs · AI for Developers
Open-source ChatGPT alternative that runs LLMs fully offline on your machine, with an OpenAI-compatible API.
References · Documentation & Learning
The Modern JavaScript Tutorial — the deepest free JS reference from basics to advanced browser APIs.
CI/CD · DevOps
The classic open-source automation server for CI/CD.
Unit & Component · Testing
Delightful JavaScript testing framework with snapshots and mocks.
State & Forms · Frontend
Primitive and flexible atomic state management for React.
CLI Tools · Development Environment
Lightweight command-line JSON processor.
JSON · Data Formats
Open-source JSON visualizer that turns data into interactive graphs.
JSON · Data Formats
Advanced JSON editor with tree view, query, transform and diff.
JSON · Data Formats
Beautiful, shareable JSON viewer with previews for many data types.
Programming Languages
High-performance language for technical and scientific computing.
Unit & Component · Testing
The standard testing framework for the JVM: annotation-driven unit tests for Java and Kotlin.
Notebooks & Data Science · Data & Analytics
The standard interactive notebooks for data science and ML.
Load & Performance · Testing
Open-source load testing tool using JavaScript test scripts.
Orchestration · DevOps
Terminal UI to interact with and manage Kubernetes clusters.
Screenshots · Image & Media
Beautiful open-source screen recorder for macOS — captures, trims and exports GIFs/MP4s with plugins.
Authentication · API Tools
Open-source identity and access management with SSO and SAML.
Terminals & Shells · Development Environment
Fast, GPU-based terminal with graphics support and layouts.
Web Servers & Proxies · DevOps
Popular open-source API gateway and microservices management.
Programming Languages
Official Kotlin language site: docs, playground and standard library reference.