diff --git a/implementations/Crafter.Graphics-UI-WebGPU.cpp b/implementations/Crafter.Graphics-UI-WebGPU.cpp
index e7cac71..865bb19 100644
--- a/implementations/Crafter.Graphics-UI-WebGPU.cpp
+++ b/implementations/Crafter.Graphics-UI-WebGPU.cpp
@@ -177,7 +177,12 @@ void UIRenderer::Dispatch(GraphicsCommandBuffer /*cmd*/, const GraphicsComputeSh
     // data at the recorded offset, look up the GPU handle in the heap,
     // and assemble a list of handles in the same order the JS bridge
     // expects (matching shader.customBindings).
-    std::vector<std::uint32_t> handles;
+    // Reuse one vector across dispatches: custom compute runs per-frame, so a
+    // fresh malloc+free each call is pure churn. thread_local keeps it valid
+    // even if dispatches ever cross threads; its capacity grows to the high
+    // water mark once and is reused thereafter.
+    thread_local std::vector<std::uint32_t> handles;
+    handles.clear();
     handles.reserve(shader.customBindings.size());
     const std::uint8_t* p = static_cast<const std::uint8_t*>(push);
     for (const auto& b : shader.customBindings) {