Uhh, I think you might be confused. Let me explain a bit more:

1. Services and Containers aren’t the same thing. The distinction usually doesn’t matter in typical self-hosting scenarios, but in this case it does.

In short: Services are what you define in a compose file; Containers are what you spin up based on those service definitions.

2. network_mode is a service attribute and it can be defined for each service separately.
3. network_mode: “service:{name}” requires the service being referenced to be part of the same stack. This is probably what you were thinking of when you wrote this reply.
4. network_mode: “container:{name}” can freely reference any preexisting container. This helps you achieve what you want. You can define your gluetuncontainer independently, along with any services you might want to be part of the same stack, and give it a unique identifier usingcontainer_name: myIndependentGluetun. After spinning it up, run your Qbittorrentcontainer or whatever service you want to route through thegluetuncontainer after addingnetwork_mode: “container:myIndependentGluetun”.