Resolving dependencies...
cabal: Could not resolve dependencies:
trying: HTTP-4000.2.18/installed-c5f... (user goal)
next goal: libjenkins (user goal)
rejecting: libjenkins-0.7.0 (conflict: HTTP =>
network==2.5.0.0/installed-ecf..., libjenkins => network>=2.6)
rejecting: libjenkins-0.6.0, 0.5.0, 0.4.3.0, 0.4.2.0, 0.4.1.0, 0.4.0.0,
0.3.0.0, 0.2.0.0, 0.1.0.0 (global constraint requires ==0.7.0)
Backjump limit reached (change with --max-backjumps).

Note: when using a sandbox, all packages are required to have consistent
dependencies. Try reinstalling/unregistering the offending packages or
recreating the sandbox.