rAthena is the server emulator behind most private Ragnarok Online servers

A continuation of eAthena, which is where its quirks come from

rAthena is a C++ implementation of a Ragnarok Online server, and the README is explicit that it continues the eAthena project. That lineage is the single most useful fact for anyone evaluating it, because it explains nearly everything about the codebase's shape. Decades of accumulated behaviour live in this tree, including behaviour that no longer matches how the retail game plays today, and the design reflects a community that has been patching the same server for a very long time rather than a team designing from first principles.

The scale of that community shows in the repository metadata: roughly 2,700 forks against about 3,600 stars. For a game server that ratio is unusual, and it means many people are running modified copies rather than contributing upstream. The README says as much, describing a collaborative project jointly managed by volunteers around the world with a community providing QA and support.

The second thing to know is what you do not get. This is a server emulator, not a game client and not a game. It speaks the protocol a Ragnarok Online client expects, so you need a client, and it stores its world in MySQL or MariaDB, so you need a database. The homepage is a forum, the wiki is a GitHub wiki, and the companion control panel is FluxCP, which is a separate repository.

Building on Linux with autotools or on Windows with Visual Studio

The README's prerequisites table is short and specific. For hardware it asks for one core and 1 GB of RAM at minimum, with two cores and 2 GB recommended, and 300 to 500 MB of disk. For the compiler it pairs Linux with gcc-6 or newer plus Make, and Windows with MS Visual Studio 2017 or newer. The database requirement is MySQL 5 or newer, or MariaDB 5 or newer, and Git is required on both platforms. MySQL Workbench is listed as optional.

The repository supports both build systems at once. On the Linux side there is `configure`, `configure.ac` and `Makefile.in`, which is a standard autotools setup, alongside `CMakeLists.txt` and `install.sh`, `uninstall.sh` and `function.sh`. The sequence is the ordinary one:

./configure
make

Windows gets the same project through `rAthena.sln` and `rAthena.slnLaunch`, and the README carries build status badges for four separate CI configurations: clang, cmake, gcc and msbuild. Four green badges for four toolchains is a decent signal for a C++ project of this size, since it means the code is not quietly relying on one compiler's leniency.

After the build, `athena-start` is the launcher, and `mac.rathena-start.scpt` in the tree suggests there is at least some accommodation for macOS hosts, though the README's supported list names only Linux and Windows.

Per-OS install guides live on the wiki, not in the README

The README's installation section is four links and nothing else: Windows, CentOS, Debian and FreeBSD, each pointing at a wiki page. That is a deliberate division of labour, and it means the README will not tell you how to import the SQL schema or where the data directory goes. If you are setting up a server, the wiki pages are the actual instructions.

What the README does contribute is the troubleshooting posture, which is honest and worth repeating. It tells you that if the server will not start, the first move is to read the console output, and that most support issues resolve from the error messages already on screen before anyone needs to answer a forum post. For a server with as many configuration files as this one, that advice is more useful than it sounds.

The community infrastructure around the project is unusually broad for something of this size: a forum with a crowdfunding board, a Discord, the GitHub wiki, a dedicated pull request Q&A thread, and FluxCP for panel management. The presence of a pull request Q&A thread is a small but telling detail, since it implies outside contributions are common enough to need a documented process.

NPC scripting is where the actual work happens

The `npc/` directory and the `doc/` directory are the reason experienced Ragnarok server operators talk about rAthena the way they do. NPCs, warps and gameplay modifications are written in a C-like scripting language rather than in C++, so a server operator changes behaviour by editing text files and reloading, not by recompiling. The README describes the project as providing NPCs, warps and modifications, and the topic list includes game-server and game-development.

The documentation in `doc/` covers NPC script commands, atcommands, group permissions, item bonuses and packet structures, and the README asks users to read that directory before asking for help elsewhere. Sample NPC scripts live there too. This is the most transferable thing in the repository: a large body of worked examples showing how quests, warps and custom behaviour are written for this specific server.

The `db/` directory holds the game data in text configuration, `sql-files/` holds the database side, and `conf/` holds server configuration. `3rdparty/` and `tools/` are present as you would expect. Understanding which of these is authoritative for a given change is the practical skill: a new item usually means editing the data files and reloading, not touching C++.

No releases published, so the branch is the version

This repository publishes no GitHub releases, which is unusual for a project of its size and tells you something about how it is versioned and deployed. There is no tag to pin, no changelog on the releases page and no packaged installer. Operators track the branch and read the commit history instead, and the default branch here is `master`.

That has a real consequence for anything automated. If you are writing a deployment script or a container image, you cannot reference a version, and `git checkout` of a specific tag is not available to you. You are tracking a moving `master`, which for a game server that people patch locally is workable, since most operators are already managing their own tree, but it does mean an unattended update can change behaviour underneath you.

The repository also carries a `Hacktoberfest` topic and `CODE_OF_CONDUCT.md`, plus `AUTHORS`, a `.mailmap` and a commit activity badge, which together suggest steady volunteer inflow rather than a fixed release team. The last push was on 2026-09-04, and the project is not archived. For an open source game server with no commercial backing, that combination is the relevant maintenance signal to weigh, more than the absence of versioned releases.

Licence terms and what a private server actually needs

rAthena is GPLv3, copyright the rAthena Development Team, and the README links the licence file directly. For anyone running a private server the licence question is not about linking the code into a larger work, since the server is normally run as-is, but about distribution and about the game data.

The bigger practical question is the client. This repository contains the server, not the game. Ragnarok Online clients are distributed separately and are not part of this project, so a working setup needs a client that matches the server's protocol expectations, a populated database from `db/` and `sql-files/`, and usually a control panel through FluxCP for accounts and web-facing administration. None of that is optional and none of it is assembled for you.

That is the honest shape of the project. It is a mature, widely forked, volunteer maintained server implementation with unusually good script documentation, and it is not a turnkey product. Anyone who wants to learn MMORPG server architecture will find more here than in most open source examples, precisely because it is a real, long-lived implementation rather than a demo.

Editorial conclusion

rAthena is the practical choice for anyone who wants to run or study a Ragnarok Online server, because it is the emulator other people actually deploy, and its NPC scripting documentation is the reference the community works from. It is the wrong tool if you want to build a new MMORPG, since the packet protocol and data model are tied to one specific game, and it will not run without a client and a database you supply yourself. Before committing, read the per-OS installation page on the wiki rather than the README, because the README is a map and the wiki is the manual, and budget for the fact that every server needs hands on NPC script work in `npc/` and SQL data in `db/` before players see anything resembling the retail game. The one core file to read first is `db/pre-re/skill_db.conf`, since almost all balance changes start there.

Frequently asked questions

Official sources

1. Issues
2. License: GPL-3.0
3. Project website
4. rathena/rathena on GitHub
5. README