Also--thanks for going on the record. You are right that you might be criticized in the future by nit-pickers, but it's much more satisfying to take public stances and find out what you're made of (in my opinion).

Big Blue Button is outstanding for any educators looking for tools. Full disclosure that it was built at the school I attended, we had a lot of profs use it and it was by far my favourite way to do distance learning.

Thanks, those are great examples. I've considered writing about Mattermost before, as I think it's a fascinating pattern that I haven't seen much elsewhere. Attack an existing, high-profile app by cloning it in the open but then additionally build a for-profit company around the clone. Truly a galaxy brain strategy.

I’ve been interested in this pattern as well. I’d contend that GitLab is another good example, and even argue that Automattic is too (IIRC Movable Type was already a successful proprietary blogging platform when WordPress came along)

Which is all to say, if you write that post, I for one will read it :)

I don't think Automattic really fits the same pattern. Although Movable Type was one of the earliest and most successful source-available blogging platforms, there were a bunch of others soon after. They all had similarities in functionality, by nature of being blogging software, but they weren't exactly "clones". WordPress was actually a fork of another early blogging software, b2/cafelog.

When Six Apart made Movable Type's license more restrictive in 2004, a portion of the userbase jumped over to WordPress. Another thing in WP's favor was ease of hosting, due to being written in PHP, vs Movable Type's Perl. This all led to a lot of momentum for WP; Automattic was founded after that, in 2005.

Thanks for the context. I wasn’t really involved in WordPress until a few years after, so the early history is foggy to me.

I'll name some more, with the same disclaimer:

Confluent (Kafka), Redis Labs, Eucalyptus Systems Inc. (AWS clone, acquired by HP), Instructure (Canvas)