I'm trying to write a compose-file using a service (node) that I'd like to scale to 3 containers. This service has a volume to be bond to my local system for persistence, but I'd like the different tasks having different binding on my system ? I tried to use the template {{.Task.Slot}} inside my docker-compose.yml as shown below, but I cannot figured out out to make it work...

version: '3.2'
services:
     node:
        build:
            context: ./node
        volumes:
            - nodeVol:/data
        command: ["myapp"]

volumes:
    nodeVol:
        external:
            name: './persistence/{{.Task.Slot}}'

Any idea of what went wrong ?