Hi Austin, devs, I'm not sure what stage the 7.10 branch split and RC have got to, but if possible I'd like to get Phab:D553 included (my special pleading is that it makes relatively small, self-contained changes that will make it slightly harder to shoot oneself in the foot when writing a plugin). I realise you have to say "no" at some point though! More generally, at Richard's suggestion I propose that (at least for 7.10) we explicitly make no guarantees about the stability of the TcPluginM API, and advertise that we may choose to make breaking changes between minor GHC releases. After all, this feature is highly experimental and tightly coupled to GHC itself. All the best, Adam -- Adam Gundry, Haskell Consultant Well-Typed LLP, http://www.well-typed.com/