I'm getting really strong deja vu from Gro.ups 2.0 - an open source social networking platform that is now entirely implemented in JavaScript widgets.

From the Product Hunt thread:

I should also note that Grou.ps v2 is actually a set of GraphJS widgets Put on top of a gorgeous Bootstrap theme. That makes it super easy for developers to (a) come up with new templates, look & feel (b) port the social functionality to other digital assets they may have, like a mobile app, WordPress blog or website (but Not cryptocurrencies LOL)

GraphJS has been around for a little while, and is designed to be an embeddable set of widgets.

Explode was an embeddable JavaScript social network I made out of Elgg almost twelve years ago. Here's the TechCrunch article from the time:

A new open source cross-site social networking service called Explode launched today and looks like a very appealing alternative to the now Yahoo! owned MyBlogLog.  Built by UK open-source social network provider Curverider (whose primary product, Elgg, is similar to PeopleAggregator), Explode offers an embeddable widget that links out to users’ respective profile pages on any social network but allows commenting and befriending in one aggregated location.  I found Explode via Steve O’Hear’s The Social Web, one of my new favorite blogs.

What's old is truly new again. It's interesting to see people experiment with open social networks in 2018 - something I spent at least a decade of my life on. More power to them.