it is possible to depend on bug-fixes in the Platform too, and they are even more subtle to know whether (or how much) you depend on the bug-fixes. API additions could at least face some automated testing... Also, does GHC have a warning-flag for all those imports that could have problems given API additions? And is there infrastructure work so that someday we might be able to take summaries of all HP APIs and run a test that tells you which HP versions your HP-using code could compile against? (at least for the relatively simple case of API *additions*) Crazy idea: What if we do the maintenance/bug-fix-only release every 4-6 weeks, and a release roughly 3 months cycle that allows API additions but no changes; and API changes are allowed only on the 6-month cycle? Then people who import carefully, only need to re-test their code twice a year. And forwards compatibility is not as bad as the 'every 4-6 weeks' situation, it's closer to 3 months. for example a series of releases in some year might look like: March: HP 2000.1.0.0 April: HP 2000.1.0.1 May: HP 2000.1.0.2 June: HP 2000.1.1.0 July: HP 2000.1.1.1 August: HP 2000.1.1.2 September: HP 2000.2.0.0 etc... -Isaac