# traceMark

`import { traceMark } from "destack:runtime";`

Append one explicit trace marker.

```ds title="traceMark"
export declare function traceMark(world: WorldHandle, label: string): Result<TraceSequence, HostError>
```

[language/library/src/runtime/trace.ds:167:170](https://github.com/destack-sh/destack/blob/main/language/library/src/runtime/trace.ds#L167-L170)