Engineering Blog

    Last Week in Unreal

    A weekly analysis of Unreal Engine commits: what changed in the engine, and what it means for teams building and shipping on Unreal.

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    Last Week in Unreal — Mar 16 – 22, 2026
    Last Week in Unreal

    Last Week in Unreal — Mar 16 – 22, 2026

    1,139 commits. Nanite ray tracing gets GPU-driven BLAS caching. SSS reworked for separated diffuse luminance. RHI submission pipeline drops latency. RigVM nativization converts Control Rig bytecode to…

    AK
    Abraham K

    Latest Articles

    Last Week in Unreal — Mar 9 – 15, 2026
    Last Week in Unreal

    Last Week in Unreal — Mar 9 – 15, 2026

    1026 commits. 20+ crash fixes across the engine. MegaLights picked up async compute and sharper denoising. A coordinated batch of programmatic toolset commits hints at AI-assisted content authoring infrastructure taking shape inside the editor.

    AK
    Abraham K
    Last Week in Unreal — Mar 2 – 8, 2026
    Last Week in Unreal

    Last Week in Unreal — Mar 2 – 8, 2026

    Lumen shed 32MB of memory with no quality regression. MegaLights absorbed cloud shadows and IES profiles — its fifth consecutive week of feature expansion. 5.7 deprecation cleanup is live: 109 files of Core/CoreUObject API removals. If you have a C++ plugin, this is your warning.

    AK
    Abraham K
    Last Week in Unreal — Feb 23 – Mar 1, 2026
    Last Week in Unreal

    Last Week in Unreal — Feb 23 – Mar 1, 2026

    Lumen and MegaLights received aggressive memory and correctness fixes — including a UNORM packing bug causing artifacts on AMD GPUs. Nanite Ray Tracing gained reference instance support for BLAS streaming, signaling a move from experimental to shippable. NVIDIA contributed Linear Swept Spheres for hair ray tracing.

    AK
    Abraham K
    Last Week in Unreal — Feb 16-23, 2026
    Last Week in Unreal

    Last Week in Unreal — Feb 16-23, 2026

    MegaLights gains front layer translucency, Substrate ships quality-level closures, Xbox GDK plugins move to public engine, and 13 crash fixes land across physics, animation, rendering, and the Verse VM.

    AK
    Abraham K
    Last Week in Unreal — Feb 9-16, 2026
    Last Week in Unreal

    Last Week in Unreal — Feb 9-16, 2026

    MegaLights gets production instrumentation while Nanite RT lands crash-grade fixes — Epic is pushing dynamic lighting toward shippable quality for 5.8. Plus a silent Chaos vehicle bug fix, a delegate lifetime overhaul that may quietly break gameplay code, and over 30 crash fixes across the engine.

    AK
    Abraham K
    Last Week in Unreal — Feb 2-8, 2026
    Last Week in Unreal

    Last Week in Unreal — Feb 2-8, 2026

    Nanite CLAS ray tracing, RHI specialization constants, mobile SSAO unification, shader packaging overhaul, and serious memory safety fixes across 867 commits on ue5-main.

    AK
    Abraham K