Not disagreeing with you or the postmortem, but:

1. that post is from Feb 8, 2016

2. nanomsg 1.0 was released on June 10, 2016

After nanomsg 1.0 release, recent activity on github includes:

8 days ago -- fixes #828 Add logical connections to UDP RFC

9 days ago -- fixes #827 nanomsg zerotier mapping rfc errors

11 days ago -- fixes #825 Extra tests in pipe.c gdamore committed 11 days ago

15 days ago -- fixes #800 accept4 not implemented on all systems

15 days ago -- fixes #783 WS transport - not connectable from Firefox

16 days ago -- fixes #821 NN_WS_HANDSHAKE_CRLF is silly

And etc.

After that, Garrett D'Amore eventually returned on condition he be BDFL. See https://github.com/nanomsg/nanomsg/issues/619

Since then the project looks to be fairly healthy.

Oh good! This is the guy behind mangos, too.

Hmm I missed it. In addition to the sibling comment above, the mangos project seems alive and well.