In a Symfony 4.3 app with `friendsofsymfony/elastica-bundle` 5.1.0, `enqueue/elastica-bundle` 0.9.3, and `enqueue/fs` 0.9.12 installation of the latter ends with:

> 
> The child node "transport" at path "enqueue\_elastica" must be
>  configured.
> 
> 
> 

I've tried multiple permutations in `enqueue.yaml`, including [the only example](https://tech.yappa.be/enqueue-symfony-console-commands) I've found.

enqueue.yaml:

```
enqueue:
    default:
        transport: '%env(resolve:ENQUEUE_DSN)%'
        client: ~

```

.env includes:

```
###> enqueue/enqueue-bundle ###
ENQUEUE_DSN=null://
###< enqueue/enqueue-bundle 

```

Elasticsearch 6.8 is installed. Relatively simple indexes are readily created. A more complex index fails with running out of memory - thus the need for `enqueue`.

What is an appropriate configuration of `enqueue.yaml` for filesystem transport?

Edit: Curiously, the Ubuntu 18 Hyper-V virtual machine was able to slog through the populating without `enqueue` while the Windows host failed at 94200/156865.