Curb (probably CUrl-RuBy or something) provides Ruby-language bindings for the libcurl(3), a fully-featured client-side URL transfer library. cURL and libcurl live at http://curl.haxx.se/.
acquired package info from repodata DB: repodata/69e709f4d2852d98f12867a74015d19384fe2727ff670fd70178cdde80b1e77e-primary.sqlite.bz2