[alserio]

I'm looking to break an old java monolith application in something like that: modular code base, single deployment artifact, multiple configurable use cases. I've yet to find a good existing tool to compose the application at build time, other than using a godawful lot of maven profiles combinations

[CharlieDigital]

Hmm; at least in the more recent versions of .NET, Microsoft has really cleaned up the runtime host paradigm so that it's consistent across console (think background services, timer jobs, pull-oriented processing) and web (classic HTTP).

For us, it just becomes a matter of configuring the correct construction of the dependency injection container at host startup using some flag (usually environment variable) to pick the right bits and pieces to load into the container and which services to run from the monolith.

Then each of the host "partitions" gets its own Dockerfile.