Design vs Testing · both proven

tailwind-design-system vs tdd

Both skills were run through Claude twice: once on a fixed brief without the skill, once with it. The briefs differ because each is written for the job the skill claims to do, so compare each skill against its own baseline, then decide which difference matters for your work. They are in different categories, so this is a choice of job, not a head-to-head on the same job.

tailwind-design-system

Build scalable design systems with Tailwind CSS v4, design tokens, component libraries, and responsive patterns. Use when creating component libraries, implementing design systems, or standardizing UI patterns.

Category: Design
Source: wshobson/agents
License: MIT
Proof model: claude-opus-5-5
Brief: “Build the shop page for Verdant, an online plant shop: a header, a filter sidebar with categories, light and price, a responsive product grid with at least nine plants drawn in inline SVG, prices, ratings, add-to-cart buttons with a cart count that updates, and a footer. It should feel like a premium storefront.”
Skill commit: 0874a27

Without the skillWith tailwind-design-system

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Without, runWith tailwind-design-system, run3 independent runs per side, none selected by hand.

Download the with-skill page

tdd

Test-driven development. Use when the user wants to build features or fix bugs test-first, mentions "red-green-refactor", or wants integration tests.

Category: Testing
Source: mattpocock/skills
License: MIT
Proof model: claude-opus-5-5
Brief: “Implement a function that parses a cron expression (the standard five fields) and returns the next run time after a given date, in TypeScript. Present the work as a single HTML page with two columns: the test file on the left and the implementation on the right, each in a code block, with a short note at the top on the order you did things in and anything you decided not to support.”
Skill commit: 5beb35b

Without the skillWith tdd

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Without, runWith tdd, run3 independent runs per side, none selected by hand.

Download the with-skill page

We don’t pick a winner for you: the pages are the evidence. Both proofs can be repeated with the brief, model and commit shown above. See alternatives to tailwind-design-system or alternatives to tdd.