This package provides facilities for parsing and unparsing URIs, and creating and resolving relative URI references, closely following the URI spec, IETF RFC 3986. In network-2.6 the Network.URI module was split off from the network package into this package. If you're using the Network.URI module you can be backward compatible and automatically get it from the right package by using the network-uri-flag pseudo-package in your .cabal file's build-depends (along with dependencies for both network-uri and network): Or you can do the same manually by adding this boilerplate to your .cabal file: That is, get the module from either network < 2.6 or from network-uri >= 2.6.