renderlint

Judgement

What it is

Developer tool

What it does

A linter for the rendered interface. It opens your app in a real browser at phone, tablet and desktop widths, then reports overflowing text, low contrast, overlaps, broken responsive layouts and emoji used as icons, with annotated screenshots and suggested fixes. It exits non-zero so it can gate a build.

Adopt it when

You let coding agents make UI changes and want an automated check that catches visual defects that type checks and ESLint miss.

Watch out

It is two weeks old with no tagged release, and its checks are heuristics that can flag intentional design choices.

Ready for

Experimental

Runs as

Command line

Built with

JavaScript, Playwright and Node.js

How established

New: started under a month ago, no tagged release yet.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: renderlint → V8 → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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