debian/watch

   1 version=3
   2 # qa.debian.org runs a redirector which allows a simpler form of URL
   3 # for SourceForge based projects. The format below will automatically
   4 # be rewritten to use the redirector.
   5 opts=pgpsigurlmangle=s/$/.sig/ https://sf.net/courier/courier-authlib-(\d+\.\d+\.\d+)\.(?:zip|tgz|tbz|txz|(?:tar\.(?:gz|bz2|xz)))