Please update darcs to build with graphviz 2999.20.0.0. On Wed, May 23, 2018 at 07:08:14PM +0200, Emilio Pozuelo Monfort wrote: > darcs can't be built anymore on sid: > > darcs build-depends on missing: > - libghc-graphviz-dev:amd64 (< 2999.19)