[phanis]

You may find it at https://github.com/orgs/segmentio/repositories?type=all

[remram]

Which is the one mentioned in the article, which is touted to be the single thing responsible for their success?

> This open-source library had only 580 lines of code

I'm sure it's in there, but even filtering out forks there's 289 results.

[phonon]

Probably this.

https://github.com/segmentio/analytics.js/tags?after=0.8.10