I built Vitest and Jest environments that give your tests real, GPU-backed WebGL and WebGPU contexts directly in Node.js. They use the same ANGLE and Dawn implementations as Chrome, so you get the same pixels without the overhead of launching a browser.
A shader can render a convincing image while its math is wrong. Numeric GPU tests exposed six bugs in Three.js's TSL foundations in a day, from NaNs to reversed rotations.
Testing command-line tools is deceptively hard - hanging processes, lost stderr, temp file juggling, and unreadable failures. I built vitest-command-line to make CLI testing in Vitest simple and robust.
A test database or API server needs to be ready before the first test and cleaned up after the last. Vitest's globalSetup handles both through one async function that can return its own cleanup.
A payment service can reach 95% code coverage while leaving retry behavior and fee disclosure untested. Intent-driven testing derives tests from declared requirements and uses specification coverage to expose those missing checks.
Code coverage tells you what code has been touched. Spec coverage tells you what intent has been verified. In the era of intent-based programming, it's time to stop measuring tests by lines of code and start measuring them by meaning.
AI coding assistants are excellent at generating tests with high coverage. But there is often a critical problem: they are testing that code behaves as written, not as intended. This "Test Theater" creates a dangerous illusion of quality while providing almost no real protection against bugs.
