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Anyone familiar with flows failing because of `Unexpected error: KeyError('lz4')`? Seems the flow itself rather than a task is failing. This is using `Docker` storage, `LocalEnvironment`/`DaskExecutor` with Dask running on Kubernetes. Seems like somehow `lz4` is not present where the job is started? I do install `pyarrow` using `python_dependencies` in the `Docker` storage so I’d expect `lz4` to be there. I’m not sure where else `lz4` could be missing.

Alternately, where is `CloudFlowRunner` being run? I assume in the flow Docker image?

Hey <@U019VJP65K8>,
Yes, I believe the CloudFlowRunner is run in the pulled image. Otherwise the KeyError is interesting, how did you setup your Docker storage?

Probably something like this?:
```with Flow(
    storage=Docker(
        python_dependencies=["pyarrow"]
    )
) as flow:```
does it persist if we add `"lz4"` there?

I used something that looked like:
```
    docker = Docker(
        python_dependencies=[&lt;elided&gt;, 'pyarrow'],
        registry_url="<http://gcr.io/&lt;elided&gt;|gcr.io/&lt;elided&gt;>")
    my_flow.storage = docker```
indeed, adding `lz4`  to that list seems to fix the issue