Epic confirms AI 'vibe coding' on Unreal Engine 6 and Fortnite

Epic Games has officially confirmed it is using AI 'vibe coding' on Unreal Engine 6, Fortnite and other projects, according to Polygon. The confirmation came from Epic Games executive VP of development Marcus Wassmer, with CEO Tim Sweeney also confirming on Sunday that Epic is using AI tools to develop code for Unreal Engine.

Wassmer said Epic's engineers no longer write the bulk of the code but instead guide the AI tools toward the desired architecture. He added that the company is iterating with AI rather than 'one-shotting' the engine, aiming to stay within memory, performance and scalability envelopes.

According to Wassmer, Epic is more concerned about moving too slowly than about skepticism toward AI. The disclosure follows earlier context: in October 2026, Epic revealed it had 'vibe-coded' a new version of the Epic Games Store launcher, which was followed by social media clips of it hallucinating and a claim that it bricked a PC. Epic also claimed the new launcher booted faster than Steam, though Valve released a store update that negated the difference.

Shift in stance

A year earlier, Sweeney had denied that Epic was using AI for Unreal Engine updates. Since then, he has said he believes a 'golden age of gaming' is imminent because of AI, and has repeatedly criticized Steam's AI disclosures as a 'political act' that 'confiscates opportunity' from developers. Epic recently delayed an unannounced Marvel and Star Wars crossover game while shifting to an 'AI-first' development approach.