QA engineer

The person who looks for ways to break something before your customer finds it by accident. They do not write the site, they check what happens when someone uses it in an unintended way: with an empty cart, a wrong phone number, a slow connection, an old phone.

When your project needs this person

For a shop, for any form that takes money or personal data, and for any project with more than one developer. Not needed for a five-page brochure site.

What happens when they are missing

Bugs get found by customers. That sounds tolerable until an order form turns out to have been broken on one particular phone for three weeks, and nobody knew because nobody complained, they just left.

How this appears in an offer

Appears as "testing" or "QA", usually with hours. If it is entirely absent from a shop offer, the developer tests their own work, which is like proofreading your own writing.

What they do NOT do

Does not fix what they find. They describe it precisely so the developer can fix it fast.