We’ll build our application by creating a brief outline of the features to work from, then filling in the details as we go along.
We’ll be developing our application interactively using the read-evaluate-print loop (REPL). This will allow us to grow the application without the need for restarts to see new functionality.
Don’t be afraid to try things out when using the REPL. For example, if you’re writing a particular function to pull some data from the database, try it right in the editor and see its output before hooking it up to the page.