# RuntimeSpeedLTO

> Generate Web code that’s optimized for runtime performance, at the expense of taking a longer time to build compared to WasmCodeOptimization.BuildTimes. Also enable an additional Link Time Optimizations (LTO) stage.

## Definition

* **Type:** Field
* **Namespace:** [UnityEditor.WebGL](/engine/6000.5/script-reference/unityeditor/webgl.md)
* **Assembly:** UnityEditor.WebGL.Extensions

```csharp
RuntimeSpeedLTO = 1
```

### Remarks

This option is the same as [WasmCodeOptimization.RuntimeSpeed](/engine/6000.5/script-reference/unityeditor/webgl/wasmcodeoptimization/runtimespeed.md) but also enables an additional LTO stage. The LTO stage is also known as Whole Program Optimization. Use this option when compiling shipping builds for deployment to end users.