Optimize Shader

Optimize Shader is an ultra-lightweight, shadowless shaderpack for Iris (Fabric) built with performance as the top priority — ideal for low-end and mobile devices.
Why it's fast
Unlike most shaderpacks, Optimize Shader doesn't add any extra composite or deferred passes, and there's no shadow map. It only overrides two core render programs — gbuffers_terrain and gbuffers_water — everything else falls back to Iris's default vanilla rendering path. That means near-zero overhead compared to running without shaders.
Features
Soft Colored Lighting — a subtle warm/cool tint blended into block and sky light, giving the world a livelier, less washed-out feel than vanilla, with virtually no performance cost (single multiply, no extra texture reads).
Water Waves — a lightweight vertex-only wave animationon water surfaces (zero fragment shader cost).
Both effects, along with wave height/speed and light warmth, are fully toggleable and adjustable from the in-game Shader Options menu.
Compatibility
Supports Minecraft Java Edition 1.21.x through 26.2 (and expected to work on 26.3+) without any version-specific code — it relies only on standard, stable Iris/OptiFine uniforms and gbuffers programs.
Requirements
Fabric Loader
Fabric API
Iris