Incremental Cooking in UE 5.7: A Dive Into the UE Cook Pipeline | Unreal Fest Chicago 2026

By default, Unreal Engine projects fully recook on every invocation: each package to ship is loaded and saved, with partial but not full caching. On large projects, it can take hours for every execution.

Since UE3, Unreal Engine has supported opt-in iterative cooking, in which only changed packages are loaded and resaved. The legacy version of iterative cooking does not detect all dependencies, however, so some packages are skipped when they should not be and stale data is used at runtime.

In UE5, we’ve added more robust dependencies into the iterative cook; this new version is now the default in 5.7 and is called incremental cooking to distinguish it from the simpler legacy iterative mode. Incremental cooking has some dependencies (ZenServer, TObjectPtr, programmer guidelines for C++ changes) that are required either for it to be enabled or for it to work correctly.

In this talk recorded at Unreal Fest Chicago 2026, we present what is necessary to make incremental cook fully enabled on your project, report the results we have seen on our internal projects, and discuss the remaining work still in progress.

Find out more about Unreal Engine here: unrealengine.com

#IncrementalCooking, #UE5.7, #ZenServer, #UnrealEngine, #UnrealFestChicago2026