Open-source alternatives to CatServer

Pumpkin is a high-performance Minecraft game server implementation designed to host shared virtual worlds. It is specifically built to support multiple client editions, allowing different game versions to interact within a single world. The project distinguishes itself through a flexible plugin architecture that supports extensions written in Go and Python. These extensions are loaded as portable binary modules, enabling developers to implement custom game logic and modify server behavior without altering the core codebase. The server covers a broad range of operational capabilities, includi

Cuberite is a high-performance multiplayer game server for Java Edition clients, designed to provide a low-memory and low-CPU environment for hosting shared virtual spaces. The server is built for cross-platform deployment across various operating systems and hardware types. It allows for the extension of game mechanics and server logic through a Lua scripting interface, enabling functionality changes without recompiling the core engine. The project includes tools for server administration via a remote console and world data management for analyzing statistics and optimizing save file storag

This project is a Java runtime diagnostic tool and bytecode instrumentation framework. It provides a remote troubleshooting interface for inspecting live Java systems, analyzing execution traces, and monitoring method performance without requiring application restarts. The system distinguishes itself through its ability to modify Java classes at runtime to capture parameters and return values, combined with a JavaScript-based scripting engine for custom diagnostic logic. It further supports collaborative live debugging, allowing multiple users to connect to a single remote process simultaneou

core-js is a comprehensive compatibility layer and standard library polyfill that implements ECMAScript proposals and stable language features across diverse JavaScript runtimes. It serves as a runtime environment shim to ensure consistent execution of global objects, iteration protocols, and standard library methods in older browsers or non-browser environments. The project is distinguished by its delivery models, offering both prototype-based global polyfilling and a pure-module implementation. This allows for the integration of modern functionality without modifying global prototypes to pr

photoshopCClinux is an automated software deployer and Linux compatibility wrapper designed to install and configure Adobe Photoshop CC on GNU/Linux systems. It functions as a specialized installer that utilizes the Wine compatibility layer to execute Windows-based imaging software. The project automates the setup of the necessary Wine environment, including the configuration of environment variables and prefix-isolated environments. This process ensures that the software and its registry settings remain separate from other Windows applications. The toolset covers the automated deployment of

JaCoCo is a Java code coverage tool and bytecode instrumenter that measures which parts of source code are executed during tests. It functions as a runtime agent to monitor application execution on the fly or as a library for offline bytecode instrumentation, allowing it to capture execution data in environments where runtime agents are restricted. The project distinguishes itself by providing both dynamic and static instrumentation paths to track execution. It includes a runtime agent for on-the-fly monitoring and the ability to modify compiled class files before execution. It further enable

Arnis is a web-based world builder and geographic data converter that translates open mapping and topographic data into three-dimensional digital maps. It functions as an OpenStreetMap terrain generator, converting real-world elevation and geographic data into playable 3D worlds. The project distinguishes itself by providing a browser-based interface for world generation, allowing users to select geographic areas and generate terrain without installing local software. It includes a cross-platform map exporter capable of producing world files compatible with various software versions and opera

817 structured cybersecurity skills for AI agents · Mapped to 6 frameworks: MITRE ATT&CK, NIST CSF 2.0, MITRE ATLAS, D3FEND, NIST AI RMF & MITRE F3 (Fight Fraud) · agentskills.io standard · Works with Claude Code, GitHub Copilot, Codex CLI, Cursor, Gemini CLI & 20+ platforms · 29 security domains · Apache 2.0

Bareiron is a minimalist environment for hosting multiplayer game servers on low-power, memory-constrained devices. It functions as a Minecraft server optimizer designed to provide basic connectivity for remote players while operating on embedded hardware with limited system resources. The software includes a hardware performance tuner that allows for the disabling of intensive game mechanics and resource-heavy features to prevent system crashes. It also incorporates a network traffic controller to adjust broadcast frequencies and tick rates, reducing bandwidth consumption and lag. The syste

This project is a PHP application server and process manager designed to reduce request latency by keeping applications resident in memory. It functions as a load balancer that distributes incoming network requests across a pool of worker processes, eliminating the overhead of repetitive bootstrapping. The server routes network requests directly into application framework kernels, bypassing traditional web server layers. It includes a built-in mechanism for delivering static assets directly to clients and supports hot reloading by monitoring source files for changes and automatically restarti

Bistoury is a production diagnostics tool for Java applications that provides a distributed debugging console, a performance profiler, and a runtime bytecode manipulator. It enables real-time application debugging and production diagnostics by analyzing running Java applications through dynamic instrumentation and state inspection. The system distinguishes itself through a remote agent manager that coordinates diagnostic connections and a runtime bytecode manipulator capable of redefining classes in memory without requiring process restarts. It features a web interface for capturing heap dump

Yabridge is a compatibility bridge that allows Windows audio plugins to run within Linux digital audio workstations. It utilizes a Wine-based wrapper to translate audio processing and plugin calls from Windows plugins to Linux hosts, supporting both VST2 and VST3 standards. The system manages the execution of both 32-bit and 64-bit Windows plugins on Linux. It includes specialized mechanisms to handle window scaling, input focus, and the transfer of data through cross-environment drag-and-drop between native Linux applications and Windows plugins. The project provides tools for environment i

XposedBridge is an Android Java hooking framework and bytecode instrumentation engine. It functions as a runtime system for intercepting and modifying Java method calls within the Android operating system and installed applications. The project provides a mechanism for zygote process injection, ensuring that all spawned applications inherit the instrumentation logic. It enables the modification of internal Android system behaviors through method proxying and Java reflection to access private internal system members. The framework supports dynamic Android instrumentation and runtime analysis,

Awesome-qr.js is a JavaScript library designed for the generation and rendering of customizable QR codes. It provides a framework for encoding data into structured bit arrays while allowing for extensive visual styling, enabling the creation of branded graphics that remain compatible with standard scanning software. The library distinguishes itself through its support for layered graphical composition, which allows users to integrate background images, animated GIFs, and center logos directly into the QR code structure. To maintain scan reliability, it employs automated image binarization, en

Task is a YAML-based task runner and build tool used to define and automate development workflows. It functions as a dependency-based build system and cross-platform task automator, allowing users to execute shell commands across different operating systems using a declarative configuration file. The project operates as an incremental build tool, utilizing file fingerprints and checksums to track state and avoid redundant work by determining if tasks are up to date. It manages execution via a dependency graph to ensure prerequisites are completed before target commands run. The system includ

01 is a voice-to-code agent and language model voice interface framework that enables natural language control of computers and devices. It functions as a real-time audio streaming server and a cross-platform voice client, translating spoken instructions into executable code to automate software, manage files, and browse the web. The system supports both local and cloud-based language models, alongside local or hosted speech-to-text and text-to-speech engines. It is designed for custom hardware integration, providing the means to build embedded AI voice controllers using microcontrollers like

qd is a server-side execution engine and request scheduler designed to automate recurring network tasks. It functions as a task automator that converts HTTP Archive files into reusable request templates for scheduled execution. The system is powered by a non-blocking server that manages a timer-driven execution engine. This allows the project to orchestrate API tasks by replaying captured network traffic and triggering network requests based on defined recurring intervals. The tool covers a broad range of automation capabilities, including schema-driven task configuration and stateless reque

Luma3DS is a custom firmware for the Nintendo 3DS that removes factory restrictions to enable the execution of unsigned homebrew and game modifications. It functions as a kernel-level system extension that hooks system calls to bypass hardware limitations and introduce new operating system capabilities. The project serves as a homebrew payload loader, using boot-time mechanisms to launch third-party software and custom firmware versions. It also provides a game modding framework capable of patching executable code and intercepting file requests to load custom assets and modified data. The en

x-cmd is an AI agent orchestrator, cloud infrastructure CLI, and cross-platform package manager that provides an enhanced POSIX shell toolkit. It integrates large language models directly into the terminal for chatting, code generation, and the execution of agentic workflows, while offering a framework for building interactive terminal user interface components. The project distinguishes itself by deploying containerized AI agents within isolated sandboxes, provisioning them with specialized skills and headless browser automation capabilities. It further streamlines development through a unif

Javassist is a bytecode engineering toolkit for analyzing, modifying, and generating Java bytecode and class files. It functions as a bytecode manipulation library that allows for the editing of class files through either direct bytecode access or high-level source code syntax. The project provides specialized tools for the programmatic creation of new Java classes and interfaces during runtime. It includes a dynamic proxy generator for intercepting method calls and a class loader interceptor that automatically modifies class definitions as they are loaded into the Java Virtual Machine. Addi

CKEditor 4 is a browser-based WYSIWYG rich text editor that enables users to create and format HTML content directly in the browser. It operates on a plugin-based architecture with a configurable toolbar system, DOM-based content editing, and an event-driven lifecycle, all delivered through a CDN-based distribution model. The editor supports skin-based theming and includes a legacy plugin compatibility layer for backward compatibility. The editor distinguishes itself as a cross-platform framework that integrates natively with Angular, React, Vue, Electron, Android, and iOS environments. It of

QEMU is a cross-platform system emulator and hardware virtualization platform that enables the execution of multiple isolated operating systems on a single host machine. It functions as a processor architecture emulator, translating machine instructions between different hardware platforms to allow software designed for one architecture to run on another. The project distinguishes itself through a modular target architecture that separates core emulation logic from specific hardware definitions, supporting a wide range of processor and peripheral configurations. It utilizes dynamic binary tra

LinuxGSM is a command-line orchestration platform designed for the deployment, management, and lifecycle maintenance of dedicated game servers on Linux systems. It functions as a system-level administration tool that automates the provisioning of server instances, ensuring they remain operational through persistent background execution, automated health monitoring, and native system-timer integration. The project distinguishes itself through a modular, shell-script-based architecture that enables multi-instance hosting on a single host. It provides granular control over server environments, i

FFmpeg Batch is a graphical desktop application designed to automate complex audio and video processing tasks. It functions as a workflow manager that allows users to execute repetitive multimedia operations in bulk, providing a centralized interface for managing encoding jobs, stream composition, and metadata across large collections of files. The application distinguishes itself by offering event-driven directory watching, which triggers automated workflows for incoming media without manual intervention. It utilizes configuration-based task templating to ensure consistent encoding parameter

Vfox is a command-line utility designed to manage multiple programming language runtimes and development tools on a single machine. It provides a unified interface for installing, switching, and configuring software versions across different operating systems, ensuring consistent development environments. The project distinguishes itself through a modular, plugin-based architecture that allows for the integration of diverse language runtimes and utilities beyond built-in defaults. It utilizes a combination of shim-based execution, symlink management, and dynamic shell-hook environment injecti

chezmoi is a command-line utility designed to manage and synchronize system configuration files across multiple machines. It uses a local Git repository as the single source of truth, allowing users to track, version, and distribute dotfiles while maintaining a consistent state across diverse operating systems and hardware architectures. The project distinguishes itself through a declarative reconciliation model that computes the difference between the current filesystem and the desired state defined in the repository. It features a robust templating engine that processes configuration files

Zellij is a terminal multiplexer and workspace manager designed to organize command-line sessions into persistent, reconfigurable layouts. It functions as a terminal plugin framework, allowing users to extend their environment with modular, event-driven components that interact with the host through a structured message-passing protocol. The project distinguishes itself through a layout-engine-based architecture that decouples visual pane arrangements from process execution, enabling automated and repeatable terminal workflows. It includes integrated support for web-based remote access, facil