Each week in my Tuesday Lunch & Learn livestream, we look at a useful technical skill, define a challenge related to that skill, and solve the challenge live. This week, it's incremental TDD.

As most people know by now, TDD is Red-Green-Refactor. It’s a series of validated hypotheses. Each time through the TDD loop, you take a small step forward. But the trick is figuring out how to take small steps.

Our challenge this week: build a ROT-13 algorithm. It’s a simple algorithm, so the challenge isn’t the algorithm itself, but building it incrementally. Each small step needs to smoothly layer onto the previous.

To follow along, download the code from GitHub and check out the 2020-05-05 tag. To see the final result, check out the 2020-05-05-end tag or view it on GitHub.

Visit the Lunch & Learn archive for more.