The phrase "AI Engineer" started appearing in job boards around late 2023. By mid-2025 it had become one of the most-searched job titles in tech. By early 2026, it's also one of the most inconsistently defined -- which means if you're targeting this role, you need to understand exactly what each employer means by it before you apply.

We spent six weeks talking to hiring managers, engineering leads, and recruiters at 12 UK technology companies -- from Series A startups to FTSE 250 businesses deploying AI at scale. What we found surprised us.