Our major goal this week was cleanup: we're planning on moving our current work to the rust-lang repository in the next week or two, so cleanup was the order of the week.
Because Cargo uses the same design as git (many plumbing commands that are used by a smaller number of high-level porcelain commands), getting a standard way to write commands with limited boilerplate was a high priority to get done before we wrote too many commands. We wrote the first few commands by hand, then extracted out some useful abstractions.
A few weeks ago, I wrote a library named Hammer.rs that allows you to decode command-line flags into a struct.
extern crate hammer;