[Haskell-cafe] Source code comprehension - Looking for ideas

Dear Haskellers, I'm involved in extending the CodeCompass (https://github.com/Ericsson/CodeCompass) source code comprehension tool with a Haskell plugin. I'm looking for ideas on views or searches (both graphical and textual) that can help programmers to understand complex Haskell programs (using compile-time information). The basic examples that I will implement is finding the definition of a name and finding usages of a name. I'm also interested in similar tools or libraries if there is any. BR, Boldizsár