Docker Compose: Volumes not working on Windows Nano

Docker Desktop
1

I’ve got two Windows Nano docker containers … one with a service on, the second with my Automated Acceptance Tests.

I’m trying to add a volume to the aat container so I can copy off the tests output.

I’ve seen elsewhere I’m supposed to use …

COMPOSE_CONVERT_WINDOWS_PATHS=1

But can’t seem to get anywhere :S

version: '3.3'

services:
  fancyservice:
    restart: always
    image: fancyservice
  aat-runner:
    environment:
      - FancyServiceUrl=http://fancyservice/
      - COMPOSE_CONVERT_WINDOWS_PATHS=1
    volumes:
      - .:/output:rw
    restart: always
    image: aat-runner

This is erroring with …

ERROR: for aat_aat-runner_1 Cannot create container for service aat-runner: invalid volume spec "/output"

ERROR: for aat-runner Cannot create container for service aat-runner: invalid volume spec "/output": invalid volume specification: '\output' ERROR: Encountered errors while bringing up the project.

Can anyone put me back on track please? :S