Alternatives to Mailman which work on Sympl

I haven’t been able to get Mailman 2 or 3 to work with Sympl, and I was wondering if anyone had suggestions for alternatives that they’ve found to work? The two features I really need are:

  1. Ability to post via email - I don’t want to use a web interface.
  2. Ability for users to subscribe via email and a web interface.

I’ve really struggled to find anything that meets these criteria and is actively maintained (e.g. majordomo is a dead project).