Developers

Modding SDK

Galactic Prospectors and Starbreaker both run on Vyrex Engine, and both load mods the same way: a folder with a manifest, scripts written in VrxScript, and art built into the engine's own file formats. Nothing here needs .NET installed. Every tool is a native build that runs on its own.

Scripts are sandboxed. They get the published gameplay API and nothing else: no file system, no network, no reflection, and a script that runs too long is stopped rather than allowed to hang the game.

Start with the API reference, then copy the sample mod and change something in it.

Get started

VrxScript API reference

The vrx file formats

The tools ship as a free download on Steam beside the games, with the sample mod and this reference inside.

Reference generated Sep 9, 2026.

The tools

Vyrex Editor

Write VrxScript, compile it to the sealed .vrxscr the game loads, and package a mod folder. The whole API is in the sidebar with completion.

Asset Builder

Turn PNG, OBJ and FBX into the vrx* containers the games read, and turn them back again.

Asset Viewer

Look at any vrx* file: meshes, textures, animations and blocks. Also renders thumbnails from the command line.

Animation Creator

Rigs and character animation. Drag a joint, it keys at the playhead; save a .vrxanm and the game plays it as an emote.

Particle Builder

Particle effects, previewed live. Drop an animated GIF or WEBP on it and it becomes a frame strip the game can draw.

Block Builder

Blocks for station and ship building: draw the outline, set integrity, mass, cost and which sides they join on.

Where mods live

Windows   %AppData%\GalacticProspectors\Mods\<your mod>\
Linux     ~/.local/share/GalacticProspectors/Mods/<your mod>/

A mod is a folder with a mod.vrxcfg manifest at its root. Enable it in the world's mod list. Load order is the list order and later wins: a mod that ships a file with the same name or id as another replaces it, including the game's own.

<your mod>/
  mod.vrxcfg                             the manifest
  Scripts/*.vrx  *.vrxscr                client scripts, source and sealed build
  Scripts/Server/*.vrxscr                host and dedicated server only
  Data/**/*.vrxcfg                       ships, craftables, drinks, keycards
  Data/Particles/*.vrxpart               particle effects
  Models/Blocks/*.vrxblk                 build blocks
  Models/Characters/Animations/*.vrxanm  emotes and character animation
  Models/Characters/<Kind>/*.vrxrig       rigs
  Textures/**/*.vrxtex  *.png            art, packed or loose

A script, end to end

on init {
    game.log("hello");
}

on tick(dt) {
}

on key(name) {
    if (name == "F6") {
        game.toast("Mod", "F6 pressed");
    }
}

Compile it in the Vyrex Editor to produce the .vrxscr beside it, drop the folder in your Mods directory, and enable it. The API reference lists every call in every namespace with its signature and an example.

Server scripts are not client scripts. Anything under Scripts/Server/ runs only on the world authority and receives the sender identity from the packet, so events cannot be spoofed by a client.

The sample mod

Samples/HelloProspector ships with the SDK and uses five of the six tools: a client script, a build block with a triangular footprint, a one and a half second salute emote, a particle effect in the text format, and the block's art as a loose PNG to run through the Asset Builder. Copy the folder into your Mods directory, enable it, and change something.

If a tool misbehaves on your machine, or the game refuses something one of them produced, say so on the forums with the file that did it.