I mentioned TDD in an earlier post, and it became clear from the responses that there's some confusion about what TDD is. TDD stands for test-driven _development_ (or design). The "test-driven" is an adjective modifying the word "development" (or "design").
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March 17, 2026 at 4:00 PM
I mentioned TDD in an earlier post, and it became clear from the responses that there's some confusion about what TDD is. TDD stands for test-driven _development_ (or design). The "test-driven" is an adjective modifying the word "development" (or "design").
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Canon TDD -- I keep reading critiques of processes that aren't TDD, so I summarized the original definition.
tidyfirst.substack.com/p/canon-tdd
tidyfirst.substack.com/p/canon-tdd
December 11, 2023 at 4:54 PM
Canon TDD -- I keep reading critiques of processes that aren't TDD, so I summarized the original definition.
tidyfirst.substack.com/p/canon-tdd
tidyfirst.substack.com/p/canon-tdd
Talk: Is TDD even relevant anymore? Yes, but don’t be dumb about it.
My @pybay.bsky.social talk slides are up
pythontest.com/tdd-pybay-20...
My @pybay.bsky.social talk slides are up
pythontest.com/tdd-pybay-20...
October 4, 2026 at 12:03 AM
Talk: Is TDD even relevant anymore? Yes, but don’t be dumb about it.
My @pybay.bsky.social talk slides are up
pythontest.com/tdd-pybay-20...
My @pybay.bsky.social talk slides are up
pythontest.com/tdd-pybay-20...
June 18, 2026 at 11:14 AM
TDD isn't design, it's design feedback: tidyfirst.substack.com/p/tdd-isnt-d...
Trying to clear up more misconceptions.
Trying to clear up more misconceptions.
TDD Isn't Design
It's Design Feedback
tidyfirst.substack.com
December 7, 2023 at 5:42 PM
TDD isn't design, it's design feedback: tidyfirst.substack.com/p/tdd-isnt-d...
Trying to clear up more misconceptions.
Trying to clear up more misconceptions.
テスト駆動開発（TDD: Test-Driven Development）の考案者 Kent Beck が TDD の定義を改めて明確化した文章を翻訳し、訳者（私）の考察を沿えています。是非ご覧ください。
【翻訳】テスト駆動開発の定義
t-wada.hatenablog.jp/entry/canon-...
【翻訳】テスト駆動開発の定義
t-wada.hatenablog.jp/entry/canon-...
【翻訳】テスト駆動開発の定義 - t-wadaのブログ
このブログエントリでは、テスト駆動開発（TDD: Test-Driven Development）の考案者 Kent Beck が TDD の定義を改めて明確化した文章を翻訳し、訳者の考察を沿えています。 きっかけ 2023年の年末、テスト駆動開発（TDD: Test-Driven Development）の考案者Kent Beckは、substackにTDDに関するポストを連投して論戦を繰り広げ...
t-wada.hatenablog.jp
March 8, 2024 at 12:15 AM
テスト駆動開発（TDD: Test-Driven Development）の考案者 Kent Beck が TDD の定義を改めて明確化した文章を翻訳し、訳者（私）の考察を沿えています。是非ご覧ください。
【翻訳】テスト駆動開発の定義
t-wada.hatenablog.jp/entry/canon-...
【翻訳】テスト駆動開発の定義
t-wada.hatenablog.jp/entry/canon-...
TDD with Rust from zero is excruciating while Go it just chugs along
October 8, 2026 at 3:01 AM
TDD with Rust from zero is excruciating while Go it just chugs along
October 3, 2026 at 2:59 PM
My thoughts on the recent TDD with LLM discussion. Theatre?
gregorriegler.com/2026/10/03/t...
gregorriegler.com/2026/10/03/t...
Gregor Riegler · TDD with LLMs: theatre?
Gregor Riegler, Software Development Coach.
gregorriegler.com
October 4, 2026 at 8:13 PM
My thoughts on the recent TDD with LLM discussion. Theatre?
gregorriegler.com/2026/10/03/t...
gregorriegler.com/2026/10/03/t...
One nice thing about tech bsky vs tech linkedin is waaaaaaaaaaay fewer TDD marketers
November 24, 2024 at 6:12 PM
One nice thing about tech bsky vs tech linkedin is waaaaaaaaaaay fewer TDD marketers
"TDD slows me down"
Good
Good
February 8, 2026 at 12:39 PM
"TDD slows me down"
Good
Good
Taste-Driven Development (TDD)
missed opportunity in place of vibe coding.
missed opportunity in place of vibe coding.
June 26, 2025 at 10:37 PM
Taste-Driven Development (TDD)
missed opportunity in place of vibe coding.
missed opportunity in place of vibe coding.
If you can get the *results* of Test-Driven Development without doing Test-Driven Development, then it doesn't matter that you didn't do TDD.
The fun starts when you try to get the results of TDD without doing TDD, and realise that TDD is actually the easiest way to get those results.
The fun starts when you try to get the results of TDD without doing TDD, and realise that TDD is actually the easiest way to get those results.
August 27, 2026 at 5:21 AM
If you can get the *results* of Test-Driven Development without doing Test-Driven Development, then it doesn't matter that you didn't do TDD.
The fun starts when you try to get the results of TDD without doing TDD, and realise that TDD is actually the easiest way to get those results.
The fun starts when you try to get the results of TDD without doing TDD, and realise that TDD is actually the easiest way to get those results.
TDD with AI is NOT TDD
February 11, 2026 at 10:56 AM
TDD with AI is NOT TDD
The last time building software sped up ~10x (early 2000s, the agile movement), a massive interest in automated testing followed almost immediately (unit tests, TDD, XP etc)
Today, building software sped up 10x, easily: and a similar massive interest in automated testing + verification is following
Today, building software sped up 10x, easily: and a similar massive interest in automated testing + verification is following
September 30, 2026 at 10:01 AM
The last time building software sped up ~10x (early 2000s, the agile movement), a massive interest in automated testing followed almost immediately (unit tests, TDD, XP etc)
Today, building software sped up 10x, easily: and a similar massive interest in automated testing + verification is following
Today, building software sped up 10x, easily: and a similar massive interest in automated testing + verification is following
Is TDD worth it when coding with AI agents?
No, TDD is a process that doesn't seem to “come natural” to models. It's like an uphill battle against the training data, and takes a lot of iterations on a prompt to get it to follow the process most of the time.
martinfowler.com/articles/exp...
No, TDD is a process that doesn't seem to “come natural” to models. It's like an uphill battle against the training data, and takes a lot of iterations on a prompt to get it to follow the process most of the time.
martinfowler.com/articles/exp...
TDD inside the agent loop - theater or actual value?
Notes from my Thoughtworks colleagues on AI-assisted software delivery
martinfowler.com
September 7, 2026 at 8:12 AM
Is TDD worth it when coding with AI agents?
No, TDD is a process that doesn't seem to “come natural” to models. It's like an uphill battle against the training data, and takes a lot of iterations on a prompt to get it to follow the process most of the time.
martinfowler.com/articles/exp...
No, TDD is a process that doesn't seem to “come natural” to models. It's like an uphill battle against the training data, and takes a lot of iterations on a prompt to get it to follow the process most of the time.
martinfowler.com/articles/exp...
Uma coisa que muita gente entende errado sobre TDD: não é sobre ter os testes durante o processo. Obviamente que os testes são um by-product adorável.
Mas TDD é muito mais sobre fazer um design de código ergonômico. Não sei explicar, mas código inspirado em TDD tem um cheiro diferente.
Mas TDD é muito mais sobre fazer um design de código ergonômico. Não sei explicar, mas código inspirado em TDD tem um cheiro diferente.
June 25, 2025 at 2:27 AM
Uma coisa que muita gente entende errado sobre TDD: não é sobre ter os testes durante o processo. Obviamente que os testes são um by-product adorável.
Mas TDD é muito mais sobre fazer um design de código ergonômico. Não sei explicar, mas código inspirado em TDD tem um cheiro diferente.
Mas TDD é muito mais sobre fazer um design de código ergonômico. Não sei explicar, mas código inspirado em TDD tem um cheiro diferente.
TDD should be more widely used - I recently recorded a conversation with @davefarley77.bsky.social and as ever we found lots to discuss about TDD. We don't always completely agree either: youtu.be/6yb7jKpxTjM?...
Should Test-Driven Development (TDD) Be Used MORE In Software Engineering?
YouTube video by Modern Software Engineering
youtu.be
August 16, 2025 at 7:50 AM
TDD should be more widely used - I recently recorded a conversation with @davefarley77.bsky.social and as ever we found lots to discuss about TDD. We don't always completely agree either: youtu.be/6yb7jKpxTjM?...
Useful for scientific practitioners of TDD (TODO Driven Development)
November 15, 2024 at 3:07 PM
Useful for scientific practitioners of TDD (TODO Driven Development)
This is a great interview. Kent Beck talks to @gergely.pragmaticengineer.com about how he's having more fun programming now with AI genies than he's had in ages. Also: the birth of Extreme Programming.
newsletter.pragmaticengineer.com/p/tdd-ai-age...
newsletter.pragmaticengineer.com/p/tdd-ai-age...
Kent Beck
Kent Beck—creator of Extreme Programming and co-author of the Agile Manifesto—reflects on decades of coding, from the birth of TDD to his experiments with AI tools shaping software’s future.
newsletter.pragmaticengineer.com
June 13, 2025 at 9:06 PM
This is a great interview. Kent Beck talks to @gergely.pragmaticengineer.com about how he's having more fun programming now with AI genies than he's had in ages. Also: the birth of Extreme Programming.
newsletter.pragmaticengineer.com/p/tdd-ai-age...
newsletter.pragmaticengineer.com/p/tdd-ai-age...
agentic coding 時代の TDD は従来の TDD から少しアレンジする方が良いという感触があって、そのあたりの道筋を見つけたら適宜情報発信していきたい
過去に何回も「死んだ」と言われてきた（その都度生き残ってきた）テスト駆動開発が、 agentic coding 時代になって AI の暴走を防ぐガードレール技術としてさらに脚光を浴びることになるとは
www.anthropic.com/engineering/...
www.anthropic.com/engineering/...
May 12, 2025 at 2:25 AM
agentic coding 時代の TDD は従来の TDD から少しアレンジする方が良いという感触があって、そのあたりの道筋を見つけたら適宜情報発信していきたい