How to Make OptiFine Custom Skies Work with Nuit

Why the Conversion Happens Automatically

If you already have a resource pack that ships OptiFine or MCPatcher custom sky files, you usually do not need to do anything special. Nuit Interop Mod scans your loaded packs at runtime and converts those legacy sky definitions into the Nuit format on the fly. The converted skies are then handed to Nuit, which renders them in place of the old OptiFine sky renderer.

Checking That It Worked

1. Load a world with the legacy sky pack enabled alongside Nuit and Nuit Interop Mod.

2. Look at the sky during the time of day or dimension the pack targets. If the custom sky appears, conversion succeeded.

3. If you see the vanilla sky instead, the pack may not actually contain OptiFine/MCPatcher sky assets, or a native Nuit/FabricSkyBoxes sky is taking priority.

When Conversion Is Skipped

The mod deliberately avoids converting a legacy sky if it detects a native Nuit or FabricSkyBoxes skybox for the same situation. This prevents duplicate or conflicting skies. If you want the converted legacy version to win instead, use the mod's option to disable native skyboxes in favor of converted ones, then reload your resource packs so the conversion runs again.