Hello Matthew, I have a question about the record pattern synonyms patch which you landed in the last month (2a74a64e8329ab9e0c74bec47198cb492d25affb). In IfaceSyn, you made the following change: data IfaceIdDetails = IfVanillaId - | IfRecSelId IfaceTyCon Bool + | IfRecSelId (Either IfaceTyCon IfaceDecl) Bool | IfDFunId I don't understand why IfRecSelIds can now store IfaceDecls. Why aren't these declarations stored at the *top level* list of declarations in an interface file? If they are, you shouldn't be storing the entire IfaceDecl structure when serializing to disk. If they are not, I am afraid I don't understand this code. I also noticed that the commit message is quite long, and many of the comments I see are not replicated anywhere in the source. Is there any reason why they should not be written down as proper notes, with cross-references from the appropriate code? Thanks, Edward