version=4
opts="filenamemangle=s%(?:.*?)?v?(\d[\d.]*)\.tar\.gz%@PACKAGE@-$1.tar.gz%,\
      uversionmangle=s/(\d)[_\.\-\+]?(RC|rc|pre|dev|beta|alpha)[.]?(\d*)$/$1~$2$3/,\
      dversionmangle=s/\+ds\d*$//,repacksuffix=+ds1" \
  https://github.com/prometheus/alertmanager/tags \
  (?:.*/)?v?(\d[\d\.]*(?:rc\d*)?)\.tar\.gz
