rr

So this is cool. The debugger "rr" approaches things from a different perspective from most debuggers. Instead of instrumenting a live, running program, it makes a thorough recording of a full run, which you can then run back and forth through with a debugger. Sounds resource-intensive, but also pretty fantastic - like the author, I hardly ever use a debugger, but even my few times using one have been characterized by shooting past the point where things actually started to go wrong.