I'm wondering if there is any special reason that download-curl is made to depend on tagsoup-0.10.1, instead of the newer version of tagsoup? At the moment this requirement is preventing download-curl from building. I have removed the dependency on tagsoup-0.10.1 and things seem to build again.
Index: haskell-packages.nix
===================================================================
--- haskell-packages.nix (revision 34376)
+++ haskell-packages.nix (working copy)
@@ -619,7 +619,7 @@
download = callPackage ../development/libraries/haskell/download {};
- downloadCurl = callPackage ../development/libraries/haskell/download-curl { tagsoup = self.tagsoup_0_10_1; };
+ downloadCurl = callPackage ../development/libraries/haskell/download-curl {};
DSH = callPackage ../development/libraries/haskell/DSH {};