How (well) does diesel deal with migrations? I've seen other ORMs fall down the stairs trying to deal with schema modification over time.
"diesel migraiton run" will run all pending migrations, there's revert/redo as well. "diesel migration generate" can generate these files and directories for you; it doesn't yet (that I know of) have helpers to write the SQL though (like Rails does for its migrations).
On deploy, it runs the migrations first https://github.com/rust-lang-nursery/thanks/blob/master/buil...
I believe there are some interesting improvements coming down the line in the future, but for now, it works pretty well.