I've got a pipeline with about 20 factors with lots of computations between the factors. And the pipeline failed with an unhelpful message:
Something went wrong. Sorry for the inconvenience. Try using the built-in debugger to analyze your code. If you would like help, send us an email. ValueError: could not broadcast input array from shape (4521) into shape (8560) There was a runtime error on line 1509.
Even the Blue Screen of Death produced more useful output than this.
Generally, how do you go about tracking a bug in a substantial pipeline? You can't trace through factors or operations on factors. You don't get a backtrace. The error messages are unhelpful. The graph draws a pretty static picture without any sense for what's happening in the pipeline during execution. When will quantopian get to improving their developer tools? You can't put together a DSL that you expect everyone to use without building better tooling around it!!!