When I try to install the gem, I get this:
$ gem install stamps
ERROR: While executing gem ... (Gem::DependencyError)
Unable to resolve dependencies: stamps requires httpi (= 0.7.9); savon requires httpi (~> 1.1.0); wasabi requires httpi (~> 1.0)
Seems like there ought to be a happy medium here - guessing that stamps would work fine on a newer version of httpi?
Just release 0.3.0 that should resolve this issue.