Open source. Open possibilities.

POCO is a collection of cross-platform C++ class libraries for building network- and internet-based applications across desktop, server, mobile, IoT, and embedded systems.

A popular single-header C++11 JSON library for parsing, serializing, and manipulating JSON with an intuitive STL-like API. Supports JSON Pointer/Patch, arbitrary type conversions, and binary formats (CBOR, MessagePack, UBJSON, BSON, BJData).

Redis is an open-source in-memory data structure server used as a cache, NoSQL database, message broker, search and vector query engine. The README covers key use cases, data types, client libraries, quick start, and source build instructions.

testssl.sh is a free, open-source command-line tool that scans servers for TLS/SSL cipher, protocol, and cryptographic flaw support on any port. It requires no installation, works across Linux, macOS, BSD, and Windows environments, and outputs results in human-readable, CSV, JSON, or HTML formats.

JSON Server is a Node.js CLI tool that turns a JSON or JSON5 file into a full fake REST API in seconds, supporting CRUD, filtering, sorting, pagination, embedding, and static file serving for prototyping and testing.

A privacy-first JSON formatter and validator that runs entirely in the browser, offering one-click formatting, invalid-JSON error messages, clipboard paste and copy, in-editor search, file upload, and light and dark themes.

Prettier is an opinionated code formatter that parses code and reprints it with consistent rules, taking maximum line length into account and wrapping when needed. It can run in editors on save, pre-commit hooks, or CI.

FastAPI is a modern Python web framework for building APIs with standard type hints, featuring automatic OpenAPI documentation, data validation via Pydantic, high performance via Starlette, and interactive Swagger UI and ReDoc interfaces.

VisiData is a terminal-based multitool for exploring and arranging tabular data, supporting formats like tsv, csv, sqlite, json, xlsx and hdf5. It runs on Linux, macOS or Windows with WSL and requires Python 3.8+.

yq is a portable command-line processor for YAML, JSON, XML, CSV, TOML, HCL, and properties files, using a jq-like syntax.

jqweb is a CLI tool that renders JSON as an interactive web page, offering jq-style queries, path navigation, and offline HTML export.

Baidu's open-source front-end low-code framework that generates admin pages from JSON config, reducing front-end development costs. It provides a visual editor, full documentation, testing workflow, TypeScript support, and community contribution channels.

A modern flat-file CMS for PHP — no database required. Stores content as JSON on disk with Twig templating, 33 built-in collection types, REST API, and a built-in MCP server for AI agents. Designed for web designers and agencies seeking structured content management without the complexity of a database backend.

A React component that declaratively builds and customizes web forms from JSON Schema, with support for multiple UI theme libraries and validators.

UE5 asset workbench plugin enables scripts and AI agents to read, edit, import, migrate, and audit Unreal Engine 5 uasset files by exporting structured JSON and applying changes via commandlets, supporting Blueprints, animations, widgets, materials, Niagara, levels, etc.

JSON Crack is an open-source tool that turns JSON, YAML, XML and CSV into interactive graphs and trees. It formats and validates data, converts between formats, generates code and JSON Schema, runs jq and JSON path queries, and exports images, with all processing done locally.

HTTPie CLI is a modern, user-friendly command-line HTTP client designed for testing, debugging, and interacting with APIs and HTTP servers.

Biome is a web project toolchain offering a formatter and linter for JavaScript, TypeScript, JSX, JSON, CSS and GraphQL. It runs via CLI or as an LSP server in editors, needs no configuration by default, and is installable from npm.

Refit is a type-safe REST client library for .NET that turns REST APIs into live interfaces, inspired by Square's Retrofit. It supports source generation, HttpClientFactory integration, and testing.

Stash is a self-hosted media organizer and server written in Go that helps you manage, tag, and stream your video and image collections, with support for community scrapers and metadata integration.