Testing can be fun, actually

Tests Are The New Moat | Daniel Saewitz

As AI becomes better at cloning people's open source work, what ends up becoming most valuable are software contracts, tests, and API surface area. This clashes the incentives of clearly defining your commercialized open source software with protecting it.

A new era for software testing - <antirez>

Hypothesis, Antithesis, synthesis

Introducing Hegel, our new family of property-based testing libraries.

regex101: build, test, and debug regex

Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java, C#/.NET, Rust.

Start Fuzzing With Zig

Fuzzing is a testing technique in which a program generates random data as input for another program to consume. The goal is to find data which could cause corruption or other fatal issues in the software that is being tested.

Does Code Cleanliness Affect Coding Agents? A Controlled Minimal-Pair Study

As autonomous coding agents see rapid adoption, their evaluation has primarily focused on task completion rates holding the target codebase fixed. This leaves a critical question unanswered: does the structural and stylistic quality, or ``cleanliness'' of the underlying code affect an agent's ability to navigate and modify it? To isolate the effect of code cleanliness from agent capability, we introduce an evaluation protocol built around minimal pairs: repositories that match on architecture, dependencies, and external behaviour, but differ on static-analysis rule violations and cognitive complexity. The pairs are constructed in both directions, by agent pipelines that either degrade a clean repository or clean a messy one. We author 33 tasks across six such pairs, evaluated through hidden tests at the application's public surface. Across 660 trials with Claude Code, code cleanliness does not change the agent's pass rate. However, it substantially alters the agent's operational footprint: agents working on cleaner code use 7 to 8% fewer tokens and reduce file revisitations by 34%. Our findings suggest that traditional maintainability principles remain highly relevant in the era of AI-driven development, shaping the computational cost and navigational efficiency of coding agents. Code cleanliness joins model choice, harness, and prompting as a factor that materially affects agent behaviours.

Test IDs are an a11y smell

Users don't use data-testid, so why do your tests?

Playtester: Alphas, Betas & Demos for Upcoming Games

Discover alphas, betas, playtests, and demos for upcoming indie and mainstream games across Steam, PlayStation, Xbox, itch.io, and more.

Learn Go by Building a Command Line Todo App | Barbarian Meets Coding

Learn the Go programming language by building a test-driven command line todo application

RegExr: Learn, Build, & Test RegEx

RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp).

Reading Code Is Hard, and tips to improve - Trisha Gee

This week's video for Dave Farley's Continuous Delivery YouTube channel is me ranting about why reading code sucks, and offering some advice on how to improve. "Every programmer occasionally, when nobody’s home, turns off the lights, pours a glass of scotch, puts on some light German electronica, and opens up a file on their computer. ... Read more

Playwright Accessibility Testing: What axe and Lighthouse Miss

axe and Lighthouse miss 60–70% of WCAG violations. Learn the limitations of automated accessibility testing and how to write smarter Playwright tests.

Review the reviews

When I was actively contributing to the Go project, my primary feed was the code review email firehose. Issues, mailing lists, and Slack had low SNR. The finished commit history was better: it was finely polished work with some of the best written commit messages I have ever encountered. But it didn’t hold a candle to code reviews for operational learning. The commit history could tell you what got done and why, in impressive technical detail.