Space Marine (2011) gets VR melee, and AI agents wrote the code

A solo developer is bringing VR melee to Warhammer 40,000: Space Marine (2011), and says AI agents reverse-engineer the engine and write the C++. The project is sm1vr. It will be free, on GitHub, with no paywall.

Warhammer 40,000 is Games Workshop’s sci-fi universe. The 2011 game is the one being converted. The latest update adds:

• Holsters on the body. Sword on the hip, pistol on the thigh, and you holster them by hand.
• Bare-fist fighting. One punch kills a gretchin, and the blood stays on your gauntlets.
• A two-hand grab. Lift an Ork horizontally and throw him.
• A hulk smash. One gretchin in each hand, smashed into each other.
• The bolt pistol, drawn from the thigh when fists aren’t enough.

The method is the unusual part. The author directs Claude agents, and they reverse-engineer the engine and write the code. The post says the author owns the result and wants people to judge it in the headset. It doesn’t say which engine the game runs on, or how far the reverse-engineering went.

To try it, you need your own copy of the Anniversary Edition of the game (the post doesn’t spell out what that edition changes). Nothing from Games Workshop is redistributed. There’s no release date; the author says it ships when it’s ready. Footage shows up first in the Flat2VR Discord, in the Space Marine VR thread under #new-vr-mods.

This is the vibe-coded wave hitting VR mods. One person directing agents to build a melee system for a game from 2011 is a real shift in who can ship this kind of work. The thing to watch is whether the code holds up once other people start testing it, not the demo clips.