Post
CD Projekt Red's in-house engine that powered The Witcher 3 and Cyberpunk 2077 — and is being retired in favor of Unreal Engine 5.
REDengine was first developed for The Witcher 2 (2011), iterated through The Witcher 3 (2015) and Cyberpunk 2077 (2020). Its strengths were dense urban environments, complex dialogue systems, and dynamic time-of-day; its weaknesses became clear with Cyberpunk's troubled launch — the engine had not been fully tested for the breadth and complexity of the open world being built on top of it. In 2022, CDPR announced it was retiring REDengine and migrating to Unreal Engine 5 for The Witcher 4 (in development) and all future projects.
Example
Cyberpunk 2077's launch troubles were partly attributed to REDengine — last-gen console hardware couldn't handle Night City's density at acceptable framerates, and CDPR's tooling for an open-world FPS was less mature than its tooling for The Witcher 3's third-person open world.
Why it matters
REDengine's deprecation is a high-profile case study in the trade-off between proprietary engines (creative control, optimization potential) and commercial engines (talent portability, tooling, and reduced risk). CDPR's UE5 pivot was widely seen as a major industry signal.
Related concepts