Individual contributor, in other words a worker as opposed to management. The author's using engineer to mean software developer; they're the workers in this context.

> as both an IC and a manager

When juxtaposed to manager, it usually means individual contributor - someone being managed rather than doing the management.

Individual contributor (as opposed to management)

Correct! IC == individual contributor. Sorry for any confusion

I believe IC is "Individual Contributor" in this context.

A most bizarre terminology the industry has come up with. Almost feels a bit derogatory.

That's the natural way languages develop, offensive terms replaces with euphemisms, given some time every euphemistic term become loaded with the same negative connotations of its origin and new euphemism get introduced.

see: https://thelingspace.tumblr.com/post/114432905996/the-euphem...

Better than grunt, peon, peasant, minion, or drone.

Itty-bitty Cog.