Philly ETE 2021 — Cutting Code Quickly: From 0% to Cleanly Refactored 100% Tested Code — Llewellyn Falco



In this guided demo, we are going to look at 3 different techniques that are remarkably powerful in combination to cut through legacy code without having to go through the bother of reading or understanding it. The techniques are:

  • Combination Testing: to get 100% test coverage quickly
  • Code Coverage as guidance: to help us make decisions about inputs and deletion
  • Provable Refactorings: to help us change code without having to worry about it
  • In combination, these 3 techniques can quickly make impossible tasks trivial

We will be doing this on the Gilded Rose Kata. It is extra beneficial if you try it out yourself first so you can see how your implementation would differ.

About Llewellyn Falco

“[After Llewellyn’s coaching] I have NEVER seen our team work so well together, so much knowledge transfer and productive work!” – Tim Falleur, Healthesystems

Llewellyn Falco is an agile technical coach who specializes in teaching teams how to slay their legacy code dragons. His style is akin to a personal trainer: working with the teams to create healthy and lasting technical habits.

He is the creator of the open source testing tool ApprovalTests, co-author of the Mob Programming Guidebook and Co-founder of He is an internationally renowned speaker who has presented over 200 conference sessions since 2009.

If you would like to get a sample of him, check out his Practical Refactoring talk.

Watch More

Check out our YouTube playlist to watch all the talks from Emerging Technologies for the Enterprise 2021.