in reply to What should be default for Net::Server - IPv4, IPv6 or IPv*

I'd opt for compatibility for now and keep the default at v4. Those who want IPv6 will have some workaround in place and will be happy to hear they can simplify their code now, and those who don't want to change their legacy applications when they get some automated upgrade needn't worry about suddenly accepting connections they may not be fully prepared to accept due to some assumptions about v4 peer addresses and similar legacy problems. In a year or two when v6 is more widespread it should be time to change the default.