From Halopedia, the Halo wiki
This article is about a game engine. For the faster-than-light propulsion system, see Slipspace drive.
The Slipspace Engine is a game engine developed by 343 Industries. The engine itself was created for Halo Infinite, allowing developers to have more creative and technical liberties when creating game environments and mechanics. The Slipspace Engine also enables Halo Infinite to evolve as a platform, with new content, mechanics, and stories being added regularly.
Around the release of Halo 5: Guardians the engine was secretly worked on, and took several years to develop. The Slipspace Engine demo unveiled at E3 2018 was the culmination of years of work, and was created to showcase the level of graphical fidelity the engine could achieve. While the engine itself is largely new, remnants of the old Blam! engine remain.
The Slipspace Engine was seen again at Xbox's 2020 Games Showcase in the form of a campaign demo for Halo Infinite.  Several criticisms were lodged towards the engine by viewers of the showcase, such as LOD pop-in, lack of detail, and low contrast in areas of shadow.
Halo Infinite was once again shown at Xbox's E3 2021 presentation with a campaign and multiplayer trailer. The Slipspace Engine received a visual upgrade, with extra detail added onto weapons, characters, and the environment.
Halo Infinite is the Slipspace Engine's debut game. Most notably, the engine allows Infinite's non-linear and sprawling campaign to function with the addition of real-time exterior lighting created by an in-game day/night cycle.