Find the best open-source alternatives

A command-line tool and framework for sampling-based performance profiling of iOS apps, generating flamecharts without Xcode.

Advanced Java date/time library with extensive calendar support, astronomy features, and superior internationalization.

A high-performance Java bean mapper offering elegance, robustness, and performance comparable to hand-written code.

A Swagger/OpenAPI toolchain for .NET, ASP.NET Core, and TypeScript that generates specifications and client code.

A library for iOS developers to adjust app constants like colors, animations, and layouts in real-time without recompiling.

An open-source implementation of Microsoft's .NET Framework for building cross-platform applications.

A Common Lisp serialization format offering rich data types, compact encoding, circular reference support, and security features.

A simple and powerful R package to create documentation websites for R packages, supporting multiple documentation frameworks.

A lightweight Python GUI toolkit for building web applications without JavaScript, web servers, or deployment hassles.

Grunt plugin to optimize PNG and JPG images using the reSmush.it web service.

Python library for multilinear algebra operations and tensor factorizations with support for dense and sparse tensors.

A Delphi VCL control for embedding and manipulating PDF documents using the PDFium library.

An open-source macOS app for elegant window management with a customizable radial menu and keyboard shortcuts.

A libre file transfer client for macOS and Windows supporting FTP, SFTP, WebDAV, Amazon S3, Azure, OneDrive, and more.

An open-source music notation software for creating, editing, and printing sheet music with WYSIWYG design.

A free, privacy-respecting, self-hostable pictionary game with no ads or accounts required.

A cross-browser screenshot and interaction testing tool for Storybook with a visual UI runner.

A modern open-source Dependency Walker rewrite for Windows developers to troubleshoot DLL load dependencies.

A proof-of-concept P2P file transfer service for Mac-to-iOS devices with zero setup during transfers.

A fast, easy-to-use macOS application for managing MySQL and MariaDB databases.

Auto-administration package for Elixir and Phoenix Framework, inspired by ActiveAdmin, to create CRUD admin interfaces with minimal code.

An open-source, self-hosted emailing platform for sending newsletters and transactional emails with enterprise-grade features.

A macOS app that captures your screen and saves it as a layered PSD file for easy editing.

A responsive layout framework for Ember.js focused on performance and maintainability with minimal runtime overhead.

An efficient and lightweight WebAssembly interpreter designed for embedded and constrained systems.

A lightweight, fast, full-text search engine for static websites, written in Rust and compiled to WebAssembly.

A fast, configurable, extensible, and beautiful drop-in replacement for golint with custom rules and strict presets.

A JavaScript parser, mangler, and compressor toolkit for ES6+ that minifies code to reduce file size.

An open-source desktop app for creating beautiful product demos and walkthroughs with screen recording, annotations, and effects.

A free, open-source, cross-platform archive manager and file utility supporting 200+ archive formats.

A free marketplace for CC0-licensed 3D assets, models, textures, and HDRI files ready for use in Three.js and React Three Fiber projects.

A lightweight and extensible infrastructure for building high-quality web applications based on ASP.NET Core.

A JavaScript library for managing tournament brackets (round-robin, single/double elimination) with full logic and storage abstraction.

An open-source authentication and user management solution with passkeys, MFA, OAuth SSO, and SAML support.

An open-source ticket selling and event management platform built on Laravel, enabling organizers to avoid third-party fees.

A scalable, distributed MQTT broker written in Rust, designed for high-concurrency IoT and M2M applications.