UI review for designers and QA

Designers and QA often inherit the same bad loop: a PR ships, someone pastes screenshots into Slack, and the argument becomes taste plus pixels instead of whether the running product matches intent. Diffraction is private MVP / design-partner ready UI review (product experience review) for UI-affecting GitHub PRs on web apps. Findings are aberrations with evidence you can replay or inspect. Tagline: See the full spectrum of every diff.

Aberration (design / QA framing): An aberration is a verified product-experience failure found while reviewing a running UI, backed by evidence a reviewer can replay or inspect, not a lone screenshot opinion.

UI review for intent: UI review checks whether the shipped experience still matches design and QA intent on the running PR head: flows, states, copy, and outcomes, not only whether a frame looks close.

You care whether the product that ships matches what was designed and what QA would sign off. The PR process often gives you the wrong artifacts for that job.

Typical failure modes:

• Review happens on mocks or Figma while the PR head drifted
• Someone drops static screenshots and debate starts without a shared repro
• Pixel baselines pass while the flow, default, or empty state is wrong
• Eng says the preview works and you cannot replay the path they mean
• Visual polish gets attention; product experience misses (blocked flows, misleading states, wrong defaults) get argued late or after merge

A broken layout can be one aberration. So can a path that looks fine in a still and fails when you click through. Diffraction's category is product experience review of the running change, not another visual QA tool.

Thesis: source correctness ≠ product correctness. Pixel sameness ≠ intent match either. Category: What is UI review?. Contrast: UI review vs visual testing.

For design partners, Diffraction is aimed at reviewing the running PR head and returning verified aberrations with evidence.

What that changes for your role:

• Faster check that the shipped UI matches intent on UI-affecting PRs
• Replay / recording-style evidence so you are not arguing from screenshots alone
• Findings tied to what a user would hit: flows, states, outcomes
• A shared artifact with eng: repro path and evidence, not a taste argument

You still own taste, specs, and test plans. Diffraction is built to make the product truth of a PR inspectable, so design and QA can verify without becoming the only humans who ever click the path.

Definitions: Glossary (see aberration).

Fit at the PR boundary, not as a replacement for design critique or full QA cycles.

1. A UI-affecting PR opens on a web app.
2. Diffraction (private MVP, design-partner scoped) exercises the PR head as a running experience.
3. Aberrations come back with evidence you can inspect or replay.
4. Design and QA review findings against intent; eng fixes or disputes with the same artifact.
5. Merge happens with fewer staging-later gaps that never get the same attention.

This does not turn every PR into a full manual QA session. It puts product experience evidence next to the diff where UI actually changed.

Cautionary tales (product experience failures, not forgotten-token stories):

Three checkboxes almost cost a billion dollars

Six people and a national signup flow

The button costing $300 million a year

Other roles: executives, engineers, and engineering leads.

If you lead design or QA on a web app and want early design-partner access to a private MVP, email hello@diffraction.sh.

Tell us how you verify UI today and where screenshot-only review keeps failing you. Design-partner interest is welcome.

See the full spectrum of every diff.