On macOS Sierra (10.12.3) with pkgsrc -current, www/serf fails to install due to a failed file permissions check: I don't see this; serf builds fine even with PKG_DEVELOPER=yes, on MacOS 10.12.4 (you're behind, since yesterdayish, but I doubt that matters). If I set my umask to 0 instead of 022, then I do see what you are reporting. Is your umask 0? If you set it to 022, does that resolve things? It's not immediately clear how pkgsrc should deal with a 0 umask. One option would be to notice and error out. Another would be to insist that all package build systems refrain from creating files with 022 set. But it is pretty clear that I don't want to do any of this during the freeze!
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