By Justin Boykin, founder of TechOpX.
Hire a restaurant integration engineer by defining which system handoffs the person will own, then testing how they handle failed orders and inconsistent data. Evaluate the candidate's production decisions alongside their knowledge of your point-of-sale (POS), ordering, loyalty, or payment platforms.
This guide uses platform documentation reviewed in October 2026 to turn integration constraints into hiring checks. The interview exercise is illustrative, rather than a customer incident or a TechOpX screening artifact.
What should the role own?
Write the brief around a flow of work, with a named owner at each system boundary. A backend engineer adding an ordering connection and an engineer maintaining several existing connections may need similar coding skills, but different production experience.
State which systems send and receive information. Then identify where the engineer's responsibility starts and ends, including the support they can expect from platform vendors and your existing team.
For an ordering role, that means specifying who owns menu updates, order submission, and status changes. For a payments role, the brief should say whether the engineer owns the payment request, the application's record of the payment, or both. List the work before adding technology requirements.
Separate what the engineer can change from what they must work around. Access to another provider's API doesn't give the engineer control over that provider's behavior or approval process. A candidate should know when to change application logic and when to escalate an issue with evidence.
Use the hospitality engineering staffing page to explore recruiting support once the responsibility is clear. The brief should still describe the work in your own systems.
Which platform details belong in the interview?
Choose constraints that affect whether the integration does its job. Ask candidates to explain how they would discover, test, and monitor those constraints.
Toast's Orders API limitations leave restaurant hours and item availability checks to the integration. A successful order submission alone doesn't establish that the integration respected either constraint.
Turn that documented behavior into a hiring question. Ask how the candidate would prevent an unavailable item from reaching checkout, and which system should supply that information. A useful answer names the data, its owner, and what the application should do if the information is missing or stale.
Keep platform familiarity proportional to the work. If a near-term release depends on a specific API, direct experience deserves weight. If the role spans several providers, also test how the candidate reads unfamiliar documentation and identifies assumptions that need verification.
How do you test experience beyond API familiarity?
Ask the candidate to trace a failure across system boundaries and explain their own contribution to a comparable repair. Keep confidential customer details out of the discussion.
Square documents that webhook notifications can repeat and arrive out of order. A webhook tells an application that an event occurred; receiving the same notification twice shouldn't cause the application to perform the same business action twice.
For a role that processes these events, ask how the candidate distinguishes an event already received from work already completed. Then ask how they recover after processing stops partway through. Their answer should explain the record they keep and how another engineer would investigate it.
Payment requests need a related check. Stripe documents idempotency keys that support retries without repeating an operation, with behavior and limits that differ by API version. A candidate should check which version and limits apply to the work.
Ask what happens when the connection fails after a payment request leaves the application. Look for a way to establish the outcome before taking another action. Repeating the request with a new identifier may create a different operation, so the explanation needs more than a general promise to add retries.
These are engineering judgment checks. Candidates can explain their decisions without disclosing code or incident records from a previous employer.
What evidence should the hiring team request?
Request an explanation of a relevant decision, supported by an example the candidate can safely discuss. A sanitized diagram or a clearly labeled exercise can help when previous work is confidential.
Use this table as an interview planning aid. It isn't a validated scoring model, and each row matters only if that responsibility belongs to the role.
Apply the same agreed criteria to candidates for the same role. Record what each person explained and which responsibility still lacks evidence, so a confident presentation doesn't substitute for an answer.
What would a useful interview exercise look like?
Use a short, fictional scenario with enough documentation to reason from. Test the candidate's assumptions and decisions, rather than memory of an endpoint.
Illustrative exercise. Your application records a payment as successful, but has no confirmed order identifier from the POS. An order-status notification then arrives twice, and your application can't yet match it to the payment record. The support team needs to know whether it can safely resubmit the order.
This is a hypothetical cross-system workflow, not a description of any provider's standard behavior. Give the candidate the relevant API contracts and sample records before asking for a proposed response.
Ask them to identify the facts they need before acting. Which request and event identifiers exist? Where could they check whether the order was created? What would make a retry safe, and which uncertainty requires escalation?
Then ask what they would change after the immediate issue is resolved. Look for a way to make the next investigation easier, with records that connect the application's actions to each provider's responses. Keep the exercise separate from unpaid production work.
What should be settled before sourcing begins?
Agree on the role's operating responsibility and who will assess it. Recruiting can find relevant experience more precisely when the hiring team has decided what evidence counts.
Put these details in a brief the interviewer and recruiter can both use:
- The systems involved and the direction information needs to travel.
- The first change or maintenance responsibility the engineer will own.
- The production access, review support, and vendor contacts available to them.
- The failures they need to investigate independently, with an escalation path for the rest.
- The job-related evidence required at the interview stage.
A contract engineer joining your team still needs someone to set priorities and review the work. If you're deciding who should manage delivery, the staff augmentation versus outsourcing comparison helps separate those responsibilities.
Once the brief names the work and its boundaries, use the contract engineering staffing process to discuss sourcing and vetting candidates against it.
