TDD Provides Robust, Human-Verified Safeguards for AI-Generated Code
With AI coding agents rapidly advancing, TDD and a test-first mindset are critically important. Human-verified test suites serve as the best guardrail, ensuring AI repeatedly produces production code that achieves desired behaviours. TDD skills are increasingly valuable as AI systems grow in capability and complexity.
Why this Workshop
Because the engineers who can TDD are the most valuable in an AI-fueled future of software.
TDD is no longer an optional skill. Engineers will either learn it the right way, or they’ll struggle and repeatedly collide with costly pitfalls.
Reduce Token Spend With TDD
Well-written tests act as precise, reusable specifications that AI coding agents can follow accurately in a single pass, dramatically cutting token usage on retries, debugging, and fixes.
They keywords are: “well-written tests”. That’s no small feat. TDD is like a martial art — best learned with the help of a skilled teacher/mentor.
Bugs Cost $$$ to Fix in Production
The trouble with estimating the cost of a defect is simple: nobody can know how high the cost will grow, nor how fast. News reels are filled with stories of simple defects that have cost companies their reputation and hundreds of millions of dollars, such as the Equifax leak, the Mt. Gox Bitcoin hack, the Boeing 737 Max crashes, the Volkswagen emissions sensor, and many more.
TDD reduces bug density by up to 80%, according to a IEEE Computer Society study in 2007. By Ron Jeffries & Grigori Melnik.
Teams often estimate that a bug in production can cost 100x more than fixing during development. But in 2004, NASA published research showing the upper range is actually 1500x. Stecklein, et al, 20100036670.
And the average cost of downtime is $300K/hour according to Gartner Research. Andrew Lerner, 2004.
How Does It Work & Who Is It For?
We write code for three consecutive days — together, 1-on-1. We practice TDD as we work through code challenges together. We begin with hypothetical tasks such as the well-known FizzBuzz or 100 Doors challenge. (wax on, wax off) Then we move to more advanced techniques involving mocks, fakes, and spies. We explore the differences between unit, integration, end-to-end, and UI testing.
Junior developers, or those new to TDD, usually leave the third day well-equipped to continue the practice and write unit tests (in their preferred language) with confidence.
Senior developers, or those with prior TDD experience, usually leave the third day well-equipped to share TDD techniques with others and perhaps to faciliate their own workshops.
Dear manager,
To produce high quality software is extremely difficult. Your developers are under great pressure to create and maintain bug-free code — so you can sleep well at night. I can help.
Contact me to discuss how my workshop will sharpen the skills in your teams. And ask me how you can personally audit the course for free.
Sincerely,
David
Dear developer,
If I could go back in time and give my younger self some advice:
- Writing code with a great mentor is the fastest way to learn how to write world-class code;
- I wish I would have learned TDD on day 1;
- And as AI becomes ubiquitous, my TDD approach is proving to invaluable.
Sincerely,
David
