On 4 𝐚𝐧𝐝 5 𝐃𝐞𝐜𝐞𝐦𝐛𝐞𝐫 2025, I’ll be hosting my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 at the 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩.
The early bird discount expires this Friday, 31/10! So don’t wait if you want to master the art of writing loosely coupled and highly maintainable automated developer tests.
Secure your spot now: https://principal-it.eu/training/well-balanced-test-driven-development.html
Here you've the slides I shared about #TestDrivenDevelopment at #JavaCro
http://tiny.cc/how-john-tdd-javacro
And here you've the feedback form, in case you can help me (1min of your time) with some words about how I can improve
http://tiny.cc/how-john-tdd-feedback
#TDD #testingFirst
Ey #Java developer!
If, by any chance, you're at #JavaCro and are interested in listening to a history about how "somebody" started to practice/use #TDD and see an example with #SpringBoot come today at 3:55 to Hall B
#TestDrivenDevelopment
https://2025.javacro.hr/eng/Agenda#:~:text=how%20John%20started%20to%20like%20TDD%20(instead%20of%20hating%20it)
How can we combine #AI with #TestDrivenDevelopment without losing the human touch? @claresudbery shares insights from her workshop "How Can You Combine AI With Test Driven Development?" and her session "Let’s Stop Making Each Other Feel Stupid" on fostering learning, psychological safety, and human-centered practices in software development.
Read the full interview https://t1p.de/d9p1z
Alternatively, with Test-Driven Development (TDD), software developers start by writing a small test then write just enough code to make it pass, and iterate — building quality into software from the get-go instead of after the fact. This approach aligns heavily with the shift-left testing philosophy where quality is built in, rather than inspected in later. (2/2)
Software developers using traditional methods start out by first writing the code. Only when the work has already been completed do they shift their focus to testing. (1/2)
Ok this is fun!
My #bzip2 implementation in #Rust is coming along nicely and I've been loosely following a #TestDrivenDevelopment approach which makes working with LLMs a breeze. If an AI assisted rework turns tests red you can immediately start debugging, tuning and optimizing, which is nice and focused.
I'm done with everything including the Move-To-Front Transform encoding and am already getting text file sizes down by 25 to 30%.
Next up: Huff huff huff!
When naming tests, avoid using technical names of functions/classes. When we encorporate the name of a function into the descriptive name of a test method, and the respective function is later renamed, then the description of the test becomes completely useless. A better approach is to describe the behaviour of the production code under test. That way we can refactor more confidently without rendering the names of our tests as obsolete.
Assertion libraries can be considered as mini-DSL’s that make automated tests more readable. When a team of devs make their choice, they usually judge on API preference. While it’s very important to have readable tests, the API should never be the deciding factor. What truly separates a good assertion library is the quality of its failure messages. The more actionable these messages, the faster you’ll diagnose the cause of failing tests.
The best thing about TDD is not necessarily the tests thats we write, but rather the instant feedback that we get from the decisions that we make during coding sessions. Especially when those decisions are related to the design of the system that we're working on.
Test doubles expose design flaws in the code. Developers usually tend to respond to the pain that this induces by blaming test doubles instead of interpreting these signals as an issue with the design. If solitary tests are amplifiers for design flaws, then test doubles will amplify these design flaws tenfold.
Small, fast-running tests quickly expose design flaws in the code. Developers usually tend to respond to the pain that this induces by blaming the tests instead of interpreting these signals as an issue with the design. Solitary tests are amplifiers for design flaws.
Imagine if only 50% of the energy that is currently used to talk about #LLMs and "#AgenticCoding", was instead used to talk, teach and practice #TDD.
Imagine what kind of #software we will have in either scenario 10 years down the line...
Should Test-Driven Development (TDD) Be Used MORE In Software Engineering? - by the channel Modern Software Engineering:
https://inv.nadeko.net/watch?v=6yb7jKpxTjM
(or YT: https://www.youtube.com/watch?v=6yb7jKpxTjM)
Today I got reminded of a great video of GeePaw Hill about the “Five Underplayed Premises Of TDD”.
1. The money premise
2. The judgement premise
3. The chain premise
4. The correlation premise
5. The driving premise
https://principal-it.eu/2025/08/five-underplayed-premises-of-tdd/
Test coverage is compound interest.
Every edge case you catch now is one less bug, one less support ticket, one more confident release.
Invest early. The payoff is peace of mind.#SoftwareEngineering #SaaSDev #CleanCode #TestDrivenDevelopment #DevLife #saasini
"So you can think really big thoughts and the leverage of having those big thoughts is just suddenly expanded enormously. I had this tweet, whatever, two years ago where I said 90% of my skills just went to zero dollars and 10% of my skills just went up a thousand X.
And this is exactly what I'm talking about. So Having a vision, being able to set milestones towards that vision, keeping track of a design to maintain the levels or control the levels of complexity as you go forward. Those are hugely leveraged skills now.
compared to I know where to put the ampersands and the stars and the brackets in Rust. You know, I'm programming in every language under the sun. And I just kind of don't care. I'm learning by osmosis. I'm learning about the languages. But, you know, and I was a language guy. I loved languages and the details of languages."
https://newsletter.pragmaticengineer.com/p/tdd-ai-agents-and-coding-with-kent
Would it be possible to transfer the test-driven development paradigm over to writing fiction? Test-driven novel writing? I think so!
Here’s my pecha kucha talk on the topic from @Oop Munich: https://youtu.be/s9rPI1lPWfc
What is Test Driven Development (TDD) and how can it speed up your software development? In this Making Tech Better podcast episode, I spoke to @GeePawHill about why he loves TDD so much and how he has spread that love to software teams all over the world.
You can listen here: https://www.youtube.com/watch?v=jJauO_q5dq8
When you do #testDrivenDevelopment, do you commit your failing test, or do you put the test and the code changes in one single commit?
