How do you validate a good design implementation?

Hello,

I am a frontend developer and have been working a lot with Designers for a long time implementing and putting designers ideas and concepts into the real world.

The idea I have been exploring is I kind of think it like "Pull requests meets Visual testing for Design tools". It is essentially giving designers a way to review the implementation of their designs, that's how I think of it the best, even though I do think this tool is effective for developers as well.

Designers and frontend developers currently rely a lot on "manually checking" design implementations are done according to the mockup that was created in Invision, Figma, Sketch or Studio. The tool would essentially take a Design (created in any of these tools), and do a match to the website that was developed showing the designer a visual diff (similar to normal visual testing tools). The designer and developer can then similar to "Pull requests" comment, and iterate on the problems shown by the tool, approving or rejecting visual diffs (menu off by 20px or buttons with more padding than in the design etc..).

I guess I keep coming back to this idea because it's just a problem I know well and I do enjoy this kind of visual testing tools. I do use visual testing tools regularly (to mostly find visual regressions) but something like this would be useful for agencies and people having to implement different designs over and over again (not my current situation anymore even though I remember the struggle well enough)

I would love to know what you think in terms of market for this idea, and if you are a designer / developer working with designs what your thoughts are on this problem and solutions out there.

Cheers!