Created attachment 423896 [details, diff] Proposed ebuild patch. There have been several releases of nanoc since the current version in Gentoo (3.8.0). It is no longer possible to follow the online instructions as they assume features which are not present in the 3.8.0 release. Please bump (patch attached).
nanoc 4.1.4 is now in the tree. Earlier versions in the 4.x series had various test failures, which is why they were not added earlier.