AI Engineer hiring kit

Every step to hire the engineer who ships features on top of large language models — and can prove they work.

About this kit — the 5Ws

An AI engineer builds product features on top of models someone else trained: chat, search, summarisation, agents. The job is less about clever prompts and more about knowing whether the feature actually works — building evaluation sets (a standing collection of test questions and correct answers used to check every change before it ships), catching regressions, and keeping cost and latency — how fast the feature responds — under control.

Calibrated for:
Mid-level through senior, individual-contributor track — this kit isn't calibrated for a first hire building an entire AI capability from scratch.
Timeline:
Set an approval-to-offer target at intake, allowing for panel availability, candidate adjustments, references and any lawful checks.
Who
Hiring managers and recruiters at software companies hiring their first or next AI engineer — including people who have never hired for this role before.
What
This kit turns 'we need an AI engineer' into a defined competency model, a job-shaped work sample built around evaluation, and consistent interview questions. It also gives you a way to check, once the hire has settled in, whether their evaluation habits actually showed up in production.
When
Use it from the moment someone says 'we need an AI engineer' — before the job is approved — and carry it through to recording how many days the hire actually took to land.
Where
Software teams shipping model-backed features.
Why
A CV lists frameworks and tools; it doesn't show whether someone built and used an evaluation set before shipping a change. The work sample and interview questions in this kit are designed to surface that specific habit directly, and applying them the same way to every candidate keeps the comparison job-related.
The competency model · 6

Use these competencies to compare job-related evidence. Review any apparent gap in a must-have before deciding.

  • Evaluation disciplineMust-have · 25

    Builds an evaluation set before trusting a change; can say how they knew a feature worked and which failure modes they measured.

  • LLM application engineeringMust-have · 25

    Has shipped features that use retrieval (finding and pulling in the right source material before the model answers), call external tools, or return answers in a required format — and can explain the trade-offs they made.

  • Production software engineeringMust-have · 20

    Writes tested, observable, maintainable code; handles timeouts, retries, rate limits and bad model output gracefully.

  • Cost, latency and reliability judgementCan learn · 10

    Knows what a request costs and how long it takes; picks a model size and caching approach on purpose rather than by default.

  • Product sense and communicationMust-have · 10

    Explains model behaviour and its limits to non-engineers in plain language; ties technical choices to user outcomes.

  • Responsible AI and safety awarenessCan learn · 10

    Spots risks such as prompt injection (hidden instructions in content the model reads, designed to hijack what it does), leaked private data, and harmful output — and designs guardrails (checks and limits that stop these problems) without being asked.

What's required and what's optional

Your hiring journey for AI Engineer. Select a stage to jump to it.

AI drafts, people decide: Use AI to draft, rewrite and summarise your own material — never to rank, score, screen out or decide on candidates, and never with a candidate's personal data.

Plan
Attract
Select
Decide
Onboard & learn

Solid = required · dashed = optional · arrow keys move between steps

Stage 1 of 13Required

0 of 3 done

Plan the role

Workforce planning and requisition approval

Who runs it
Hiring manager + finance / HR business partner
Done when
An approved requisition with a written business case, budget and a named decision-maker.
Three ways to meet the needConsider growing the existing team, bringing in temporary help or hiring permanently. Record the choice, budget and approver.What work needs doing?Build:grow theteamBorrow:bring inhelpBuy:hirepermanentlyRecord the choice, budget and approver

Key tool

Answer these before the role is approved

  1. 1Which model-backed features will this person own in their first year?
  2. 2How do we know today whether those features give correct answers?
  3. 3Could an engineer already on the team grow into this role within the next two quarters?

AI as an advantage4D framework

Delegate
Hand AI the first draft of the business case and the build / borrow / buy comparison. The decision, the budget and the sign-off stay with people.
Show the prompt and the checks
Describe

You are helping a hiring manager write a business case for an AI Engineer role. Context: I will paste the problem the hire solves, the work it involves, the capacity we already have and the time we have. Produce: (1) a one-sentence problem statement in business terms; (2) a build / borrow / buy comparison with the strongest argument for each; (3) the questions a finance partner would ask; and (4) a short recommendation with the evidence it rests on. Use British English and plain language. Do not invent figures — leave [brackets] where I need to supply numbers. Ask me questions if anything is missing. Rule: do not ask for, and I will not paste, candidate names, interview notes, CVs, submissions or any other personal data. If any appears, stop and tell me to remove it.

Discern
Check every number and claim against your own notes and strike anything the draft assumed. Make sure 'buy' is argued from ongoing work, not from a job title.
Diligence
The hiring manager owns the final case and the budget request. No candidate information belongs here; AI drafts the case, people decide whether to open the role.

Don't miss: Posting an 'AI engineer' requisition to match a competitor's job board, with no specific model-backed feature already waiting for this person to own.

General information, not legal advice. Rules depend on the employer, the role and where the work is done — confirm what applies with HR or counsel.

Frequently asked questions

Where does this role stop and a machine learning engineer's begin?

The titles overlap in practice. An AI engineer role centres on product features built with existing or adapted models; a machine learning engineer role centres on data, training and production model systems. Fine-tuning, serving and evaluation work can sit in either role, so define the boundary from what your team actually needs, not the job title alone.

How long does it take to hire an AI engineer?

With this process, plan for four to six weeks from an approved requisition to an accepted offer. Scheduling and offer approval are the two places delay creeps in most easily — settle the pay band and hold panel time before the first candidate arrives.

Should candidates be allowed to use AI tools in the work sample?

Yes, where your company's AI-tool policy allows it. Say so in the brief, ask candidates to tell you which tools they used and how, and assess whether they checked what the tools produced rather than accepting it as-is.

What is the most important skill to test?

Evaluation discipline — the habit of measuring whether a feature works before trusting a change. It's the clearest difference between someone who has shipped reliable AI features and someone who has followed tutorials.

How many interview rounds does an AI engineer need?

Start with the work sample and three focused interviews. Add another stage only when it tests a distinct, job-related criterion not covered elsewhere.

Do we need an AI engineer or a strong software engineer?

Map your model-backed features, how much evaluation and fixing each one needs, and who does that work now. When that list adds up to ongoing quality work that doesn't fit alongside existing jobs, a dedicated AI engineer makes sense.

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