Sites like papermc.io

Purpur, an open source Minecraft server software project by PurpurMC, with documentation, Bukkit API docs and downloads

GeyserMC, a project site offering downloads, API documentation and wiki pages for Geyser, a Java-to-Bedrock Minecraft bridge

MohistMC is a project site for community-driven hybrid Minecraft server software such as Mohist and Youer, with docs and team pages

EngineHub: an open-source collection of Minecraft mods, plugins and tools such as WorldEdit and CraftBook

Sponge, an open-source modding API and plugin platform for Minecraft: Java Edition, run by the SpongePowered community project

PlaceholderAPI, a Minecraft Java Edition plugin page that lets server plugins display their information in other places

Maddy Miller's personal portfolio and contact site, covering her Minecraft mods WorldEdit, WorldGuard and CraftBook plus software engineering work

The NeoForged project's website for NeoForge, a open-source modding platform for Minecraft, with installers, mod development guides and changelogs

PufferPanel, an open source web panel for installing and managing game servers such as Minecraft and Source dedicated servers

Pterodactyl is a free, open-source web panel for self-hosting and managing game servers in Docker containers

Prism Launcher: a free open-source Minecraft launcher for managing multiple game instances, accounts and mods, forked from MultiMC

Documentation for Multiverse, a family of Minecraft server plugins for managing worlds, portals, inventories and anchors

Quilt, an open-source Minecraft modding toolchain and mod loader project run by a community, with its documentation and downloads

MCStacker, a set of web tools generating Minecraft commands for stacking items, NPCs and pixel art murals

Seeder, an interactive Minecraft seed map and finder by TrinTragula for Java and Bedrock editions, with seed lists

Vintage Story, a wilderness survival sandbox video game set in a ruined, temporally disturbed world

Codefling is a marketplace and community hub for Rust game server plugins, maps and prefabs, with curated collections

WinSCP, a free open-source SFTP and FTP client application for Windows file transfers between local and remote computers

WindowsGSM is a free tool for managing and hosting multiplayer game servers on Windows, with a GUI and GitHub repositories

MultiMC is an open-source alternative Minecraft launcher for managing separate instances with their own mods and saves, by peterix

Pelican is a free, open-source web control panel for hosting and managing game servers in Docker containers

BentoBoxWorld is the documentation and support site for BentoBox, a Minecraft server plugin for island-based game modes

Open Multiplayer, an open-source multiplayer server software for San Andreas Multiplayer (SA:MP) game clients and scripts

Sinytra, a project making cross-platform Minecraft modding tools such as Connector for running Fabric mods on NeoForge

Linkwarden, an open source bookmark manager for saving, annotating and preserving web pages, with apps and a browser extension

A free open-source web-based manager for starting and administering Minecraft servers, with downloads for Docker, Linux and Windows

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Factorio, a factory-building video game by Wube studio in Prague, with its official news blog of Friday Facts updates

Universal-Team, a homebrew software group making games, save editors and tools for Nintendo DS and 3DS consoles

A Swiss-run collection of cozy Minecraft mods for farming, cooking, building and decoration, presented as a mod catalogue

mailcow: dockerized news blog from The Infrastructure Company GmbH on the mailcow open-source mail server suite, with release updates

Chips and Cheese, a Substack newsletter of deep-dive articles on computer hardware, software and the wider tech industry

NamelessMC, an open source website software package for Minecraft communities, with release news and a community forum

Blueprint, an open-source extension framework and platform for modding the Pterodactyl game server control panel, with docs, guides and releases

Shields.io is a service that generates concise, consistent badges for GitHub readmes and other web pages

A browser-based Minecraft 1.8 seed map and location finder for exploring worlds by seed

Koin, an open-source dependency injection framework for Kotlin and Kotlin Multiplatform, documented by Kotzilla and its contributors

Beszel, a lightweight self-hosted server monitoring tool with Docker stats, historical data, alerts, and GPU monitoring

DMP is a multiplayer mod for Kerbal Space Program, with downloads for its client, server and updater tools

HelloGitHub is a Chinese-language periodical and project-discovery platform showcasing beginner-friendly open-source GitHub projects, published monthly

Documentation for Starboard, a Discord bot that pins popular messages to a highlights channel via reactions

Paymenter is an open-source billing and payment management platform for hosting providers, with API docs and brand assets