Welcome

Railroader is an operations-focused railroad simulator set in transition era Appalachia. Manage and run your railroad to your desire while using period steam and diesel locomotives and rolling stock. You can buy Railroader now — it’s in Early Access on Steam!

This is the official documentation site for Railroader. Most of what’s here is technical documentation for modders, but we may expand it to cover the gameplay in the future. Check out the sidebar for the full contents, or read on for the highlights.

New in the MoW Update

We’ve been putting a lot of work into building official modding support for the MoW Update (0.6). It currently supports:

• Integrated mod management. The mod loader is built in; no UMM or other third-party tools.
• Rolling stock and locomotives. Your own models, textures, and sound, built with the ADK.
• Paint and swappable parts. Styles for colors, lettering, and heralds; toggleable parts for pilots and stacks.
• Scripting. Relay runs sandboxed in-game. Data.rl reshapes definitions and map data; Main.rl adds behavior, UI, and commands.
• Custom maps. The new Map Editor builds from scratch, or extends the existing map.

The MoW Update is on the Experimental branch while we work on it. We want to hear from you what works and what doesn’t. What do the tools not support that they should? We plan to expand their capabilities over time; our priority is to build a stable foundation for the future of Railroader.

Where to Start

A lot has changed in 0.6, which will require updating existing mods. For many mods we expect this to be straightforward; more sophisticated mods will take more careful consideration.

If you’re the author of a mod for Railroader 2025.1.x, see Migrating Mods for guidance on updating your mod for 0.6.

If you just want to run a mod someone else made, see Installing Mods. There’s nothing to build.

If you want to make one, read Modding first — it covers what’s supported and what isn’t. Then Creating a Freight Car walks through the whole thing, from a model in your 3D tool to a car running in the game.

If you’re looking something up, try Definitions, Components, or the Relay API.