str50 [1] filed a orphan request for ns3 [2]: Last stable release was in October 2016. Also the install script provided as-is has issues and maintainer provided no response. (See my comment) https://www.nsnam.org/news/ns-3-26-released/ [1] https://aur.archlinux.org/account/str50/ [2] https://aur.archlinux.org/pkgbase/ns3/