NixOS has updated to Yesod 1.4 a while ago, but unfortunately this broke the Hydra CI build at
http://hydra.cryp.to/build/209093/nixlog/1/raw. Is there any chance that hledger could support the recent version?
web: require yesod 1.4; dependency cleanups (fixes #212)
I think requiring the current yesod libs is ok.
Dropped support for: shakespeare 1.*, blaze-html 0.4, probably GHC 7.4.