#testdrivendevelopment — Public Fediverse posts

𝐓𝐨𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27, is the last day to secure your spot at the 𝐞𝐚𝐫𝐥𝐲-𝐛𝐢𝐫𝐝 𝐫𝐚𝐭𝐞 for my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭. Join us on 𝐌𝐚𝐲 21-22, 2026 at 𝐓𝐡𝐞 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩 .

Don’t miss this final chance to invest in your skills at a reduced price.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐧𝐨𝐰.

For more information: https://principal-it.eu/training/well-balanced-test-driven-development.html

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

𝐓𝐨𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27, is the last day to secure your spot at the 𝐞𝐚𝐫𝐥𝐲-𝐛𝐢𝐫𝐝 𝐫𝐚𝐭𝐞 for my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭. Join us on 𝐌𝐚𝐲 21-22, 2026 at 𝐓𝐡𝐞 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩 .

Don’t miss this final chance to invest in your skills at a reduced price.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐧𝐨𝐰.

For more information: https://principal-it.eu/training/well-balanced-test-driven-development.html

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

𝐓𝐨𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27, is the last day to secure your spot at the 𝐞𝐚𝐫𝐥𝐲-𝐛𝐢𝐫𝐝 𝐫𝐚𝐭𝐞 for my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭. Join us on 𝐌𝐚𝐲 21-22, 2026 at 𝐓𝐡𝐞 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩 .

Don’t miss this final chance to invest in your skills at a reduced price.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐧𝐨𝐰.

For more information: https://principal-it.eu/training/well-balanced-test-driven-development.html

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

𝐓𝐨𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27, is the last day to secure your spot at the 𝐞𝐚𝐫𝐥𝐲-𝐛𝐢𝐫𝐝 𝐫𝐚𝐭𝐞 for my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭. Join us on 𝐌𝐚𝐲 21-22, 2026 at 𝐓𝐡𝐞 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩 .

Don’t miss this final chance to invest in your skills at a reduced price.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐧𝐨𝐰.

For more information: https://principal-it.eu/training/well-balanced-test-driven-development.html

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

𝐓𝐨𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27, is the last day to secure your spot at the 𝐞𝐚𝐫𝐥𝐲-𝐛𝐢𝐫𝐝 𝐫𝐚𝐭𝐞 for my workshop 𝐖𝐞𝐥𝐥-𝐁𝐚𝐥𝐚𝐧𝐜𝐞𝐝 𝐓𝐞𝐬𝐭-𝐃𝐫𝐢𝐯𝐞𝐧 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭. Join us on 𝐌𝐚𝐲 21-22, 2026 at 𝐓𝐡𝐞 𝐁𝐫𝐚𝐢𝐧 𝐄𝐦𝐛𝐚𝐬𝐬𝐲 𝐢𝐧 𝐀𝐧𝐭𝐰𝐞𝐫𝐩 .

Don’t miss this final chance to invest in your skills at a reduced price.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐧𝐨𝐰.

For more information: https://principal-it.eu/training/well-balanced-test-driven-development.html

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Letting the implementation details of the Subject Under Test seep into your test code quickly becomes problematic. It harms readability, forcing readers to decipher the test’s behavior, sometimes even debug it, just to understand what’s happening. Tests should be simple and easy to understand! That’s why it’s crucial to keep the domain knowledge in the production code, and out of your tests.

https://principal-it.eu/2020/09/prevent-domain-knowledge-from-sneaking-into-solitary-tests/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Letting the implementation details of the Subject Under Test seep into your test code quickly becomes problematic. It harms readability, forcing readers to decipher the test’s behavior, sometimes even debug it, just to understand what’s happening. Tests should be simple and easy to understand! That’s why it’s crucial to keep the domain knowledge in the production code, and out of your tests.

https://principal-it.eu/2020/09/prevent-domain-knowledge-from-sneaking-into-solitary-tests/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Letting the implementation details of the Subject Under Test seep into your test code quickly becomes problematic. It harms readability, forcing readers to decipher the test’s behavior, sometimes even debug it, just to understand what’s happening. Tests should be simple and easy to understand! That’s why it’s crucial to keep the domain knowledge in the production code, and out of your tests.

https://principal-it.eu/2020/09/prevent-domain-knowledge-from-sneaking-into-solitary-tests/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Letting the implementation details of the Subject Under Test seep into your test code quickly becomes problematic. It harms readability, forcing readers to decipher the test’s behavior, sometimes even debug it, just to understand what’s happening. Tests should be simple and easy to understand! That’s why it’s crucial to keep the domain knowledge in the production code, and out of your tests.

https://principal-it.eu/2020/09/prevent-domain-knowledge-from-sneaking-into-solitary-tests/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Letting the implementation details of the Subject Under Test seep into your test code quickly becomes problematic. It harms readability, forcing readers to decipher the test’s behavior, sometimes even debug it, just to understand what’s happening. Tests should be simple and easy to understand! That’s why it’s crucial to keep the domain knowledge in the production code, and out of your tests.

https://principal-it.eu/2020/09/prevent-domain-knowledge-from-sneaking-into-solitary-tests/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Due to popular demand, I’ve extended the early-bird discount 𝐮𝐧𝐭𝐢𝐥 𝐌𝐨𝐧𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27! Don’t miss this opportunity to invest in your skills at a reduced rate.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐭𝐨𝐝𝐚𝐲 and learn how to build tests that support your development process (see link in the comments)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

(2/2)

Due to popular demand, I’ve extended the early-bird discount 𝐮𝐧𝐭𝐢𝐥 𝐌𝐨𝐧𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27! Don’t miss this opportunity to invest in your skills at a reduced rate.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐭𝐨𝐝𝐚𝐲 and learn how to build tests that support your development process (see link in the comments)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

(2/2)

Due to popular demand, I’ve extended the early-bird discount 𝐮𝐧𝐭𝐢𝐥 𝐌𝐨𝐧𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27! Don’t miss this opportunity to invest in your skills at a reduced rate.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐭𝐨𝐝𝐚𝐲 and learn how to build tests that support your development process (see link in the comments)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

(2/2)

Due to popular demand, I’ve extended the early-bird discount 𝐮𝐧𝐭𝐢𝐥 𝐌𝐨𝐧𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27! Don’t miss this opportunity to invest in your skills at a reduced rate.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐭𝐨𝐝𝐚𝐲 and learn how to build tests that support your development process (see link in the comments)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

(2/2)

Due to popular demand, I’ve extended the early-bird discount 𝐮𝐧𝐭𝐢𝐥 𝐌𝐨𝐧𝐝𝐚𝐲, 𝐀𝐩𝐫𝐢𝐥 27! Don’t miss this opportunity to invest in your skills at a reduced rate.

🔗 𝐒𝐞𝐜𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐬𝐩𝐨𝐭 𝐭𝐨𝐝𝐚𝐲 and learn how to build tests that support your development process (see link in the comments)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

(2/2)

Yay! The tests I wrote this evening failed! And then after I wrote a bit of code most of them passed. Bit more to do tomorrow.

#TestDrivenDevelopment #IDeserveCake

New article: Tales Of TDD - One Test Double To Rule Them All
A short story about the pragmatic use of test doubles.
https://principal-it.eu/2026/03/tdd-tales-one-test-double/

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

Without proper TDD, developers keep pinging Google AI Studio to generate missing unit tests, turning AI assistance into a reminder service. Discover why solid test‑driven practices still matter for reliable AI‑powered code and how open‑source teams can avoid this trap. #AIStudio #TestDrivenDevelopment #UnitTests #GoogleAI

🔗 https://aidailypost.com/news/lack-tdd-forces-constant-reminders-google-ai-studio-tests

A story about why #TestDrivenDevelopment matters

This week, I have been working on an invoicing system in a legacy codebase. The requirements are to extend the invoice report with additional custom fields. What we'll test here is not the visual, but the (in-memory) field values that are ultimately displayed on the invoice report.
So I first wrote the test for the header fields, _let the test fail_, and continued with the actual implementation until the test passed...

1/?

#SoftwareEngineering

This book was published in 2003, which is also the year that I read it. The sentence “A developer is a tester is a developer” has always stuck with me. Unfortunately, in 2026, not much has changed. There is certainly a correlation between quality and ownership of testing. Software teams that adopt a holistic approach, where everyone is responsible for quality, will always outperform those that don’t. (2/2)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

One of the books that had a profound impact during my early years as a software developer was “Debugging Applications for Microsoft .NET and Microsoft Windows” by John Robbins. I fondly remember the following paragraph from one of the first chapters of the book. (1/2)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

However, developers are often conditioned to believe that their work should always involve complexity.
“Easy things? Is that a joke? We’re software engineers! Complexity is our trade.”

This is one of the main reasons why many people are turned off by Test-Driven Development. But if you can move past this mindset, you’ll be in a much better place. I favour small, ridiculous steps over larger steps that feed into complexity any day.

#tdd #testdrivendevelopment #unittests #softwaredesign

Getting the genie (as @kentbeck calls it) to perform #TDD (Test-Driven Development) is... interesting.

#TestDrivenDevelopment #Software #Programming #AutomatedTests #AI #LLM #AIAssistedDevelopment #VibeCoding #AugmentedCoding

Getting the genie (as @kentbeck calls it) to perform #TDD (Test-Driven Development) is... interesting.

#TestDrivenDevelopment #Software #Programming #AutomatedTests #AI #LLM #AIAssistedDevelopment #VibeCoding #AugmentedCoding

Getting the genie (as @kentbeck calls it) to perform #TDD (Test-Driven Development) is... interesting.

#TestDrivenDevelopment #Software #Programming #AutomatedTests #AI #LLM #AIAssistedDevelopment #VibeCoding #AugmentedCoding

Getting the genie (as @kentbeck calls it) to perform #TDD (Test-Driven Development) is... interesting.

#TestDrivenDevelopment #Software #Programming #AutomatedTests #AI #LLM #AIAssistedDevelopment #VibeCoding #AugmentedCoding

Getting the genie (as @kentbeck calls it) to perform #TDD (Test-Driven Development) is... interesting.

#TestDrivenDevelopment #Software #Programming #AutomatedTests #AI #LLM #AIAssistedDevelopment #VibeCoding #AugmentedCoding

Test-Driven Development and software design are two sides of the same coin. However, one doesn’t automatically lead to the other. We have to learn about what good design entails, while also learning and practicing Test-Driven Development in conjunction with each other.

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

I've a bright, enthusiastic developer started on my team today. As well as in-person mentoring, what book would to recommend to get started with #TestDrivenDevelopment #TDD #programming ?

These are ones that received their share for 2025:
- Elephant Haven
- De Zonnegloed
- Knaagje
- VOC Brasschaat
- Forrest and Friends
- Lwiro Primates Rehabilitation Center
- Ongehoord
- Dryade
- Sea Shepherd Belgium
- Sheldrick Wildlife Trust

(2/2)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

On the first day of the new year, I divide all the proceeds of my book to animal welfare organisations. When you buy a copy of my book, you’re not only learning about unit tests, you’re also providing a helping hand to these organisations. Thanks to everyone who purchased my book in 2025!
https://principal-it.eu/books.html

(1/2)
#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

"A computer can never be held accountable. That’s your job as the human in the loop.

Almost anyone can prompt an LLM to generate a thousand-line patch and submit it for code review. That’s no longer valuable. What’s valuable is contributing code that is proven to work.

Next time you submit a PR, make sure you’ve included your evidence that it works as it should."

https://simonwillison.net/2025/Dec/18/code-proven-to-work/

#AI #GenerativeAI #AIAgents #SoftwareTesting #Programming #LLMs #CodingAgents #TestDrivenDevelopment

Hey all, @kentbeck is livestreaming! https://www.youtube.com/watch?v=ouGJSC5SdRQ

#Programming #Python #TDD #TestDrivenDevelopment #Genie #LLM #AI #VibeCoding #AIAssisted #SoftwareEngineering

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

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

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

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

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

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

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)

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)

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)

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)

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)

Next Wednesday, October 15, starting at 18:45 we’re holding the #Meetup "TDD & DDD From The Ground Up by @ChrisSimonAu at N26's office.

Check out more information and confirm your attendance at:
https://www.meetup.com/dddbcn/events/311446227/

#DDD #DDDesign #DomainDrivenDesign #DDDBCN #TDD #TestDrivenDevelopment

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)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

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)

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign

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.

#tdd #testdrivendevelopment #unittests #softwaredesign

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.

#tdd #testdrivendevelopment #unittests #softwaredesign

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.

#tdd #testdrivendevelopment #unittests #unittesting #softwaredesign