> Explore the problem you are facing with quick prototyping in the repl and see the blind spots, the unknowns, the shape of data received from flaky integration

> Explore the problem you are facing with quick prototyping in the repl and see the blind spots, the unknowns, the shape of data received from flaky integrations. Mold and shape your functions as the problem becomes clearer. This is a great way to end up with undocumented code with no tests. The repl definitely encourages this process, but you should be doing this via quick running unit tests rather than the repl so that when you are done you already have a set of tests. Otherwise tests are an after thought and usually after thoughts are either not done or done poorly. edit: you can always run your unit tests via the repl too, if you'd rather not use a fast test runner.