I actually just discovered Outline yesterday! It's an awesome platform. Our feature set isn't as extensive (yet), especially when it comes to integrations—they've really nailed that. However, many of the other features, like live collaboration and better security, are things we're actively working on and should be available in the next few releases.

One major difference between Outline and Kalmia is the license. I believe Outline uses BSL, while Kalmia is AGPL.