Toast Coding Interview Questions: Coding, Restaurant Platform and APIs

Toast, headquartered in Boston, sells a point-of-sale and management platform built for restaurants: Android-based terminals and handhelds, payments, online ordering, kitchen display screens, and payroll and team tools. Candidates describe practical coding framed around restaurant scenarios, sometimes in a pair-coding style, and design questions about keeping a restaurant running when the internet drops. This page covers what Toast builds and who it hires, the process candidates commonly report, the technical depth the teams care about, representative problem types, what interviewers score, and a three-week prep plan.

What Toast builds and who it hires

Toast's engineers build the Android point-of-sale app that runs in the restaurant, the cloud services behind it, payment processing, online ordering and delivery integrations, the kitchen display system, and payroll and scheduling. Job posts describe the Android app as written in Java and Kotlin, and a post on Toast's technology blog says the company maintains more than 100 plain Java and Kotlin libraries shared between point-of-sale and server code, some compatible back to Android 4.4. Toast's developer documentation says a device enters offline mode 40 seconds after it loses internet, can still take cash and card payments, and can sync orders locally through a hub device on the restaurant's network.

• Android engineers: the point-of-sale, handheld and kitchen display apps.
• Back-end engineers: Kotlin and Java services for orders, menus and restaurant data.
• Payments engineers: card processing, refunds and offline payments.
• Web and integrations engineers: online ordering, the restaurant dashboard and partner APIs.

What the process tends to look like

Processes differ by team, level and office and change over time, so treat this as the common shape candidates report and confirm the specifics with your recruiter.

Offline-first restaurants and payments

Offline first. When a restaurant's internet fails, servers still need to take orders and payments. Explain what each device keeps locally, how it queues changes for the cloud, and how you would resolve a conflict when two terminals edited the same open check, a probe candidates report.

Shared code across device and server. With libraries shared by the point of sale and the back end, a change can break an older Android device in a restaurant you cannot reach. Discuss versioning, backward compatibility and testing on old OS versions, and know Kotlin and Java well. Our Android interview questions and Kotlin interview questions help.

Payments. Know authorization versus settlement, tokenization, refunds and voids, and the extra risk of taking a card payment while offline. Idempotency matters when a handheld retries a payment over flaky Wi-Fi. Our system design walkthroughs for marketplaces, maps and payments cover a payments flow.

The dinner rush. Traffic arrives in sharp peaks at lunch and dinner, and a slow terminal costs a restaurant money in real time. Tie your design choices to a server with a full section or a cook watching the kitchen display, because interviewers look for that product sense.

Representative problem types

These are the kinds of problems candidates describe, not a leaked question list. Practice the category, not the exact question.

1. Route order items to kitchen stations and display them in firing order with a queue or heap.
2. Split a check between guests with tax and tip rounded correctly.
3. Manage a waitlist or seating list with priorities.
4. Merge orders from two devices that were offline at the same time.
5. Design online ordering with live menu availability across many locations.
6. Review a code snippet for logic errors and performance problems.
7. Medium problems on arrays, graphs, matrices and sliding windows.

What interviewers score

• Working code: a solution that runs, handles edge cases and is readable by the next engineer.
• Practical judgment: the trade-offs you name and the simplest design that meets the requirement.
• Product sense: understanding who the user is and what failure looks like for them.
• Ownership: examples where you shipped, measured and fixed things yourself.

The behavioral side

Technical rounds decide most outcomes, but every Toast loop also asks about how you work. Prepare a short story for each of these, with a result and what you learned:

• Something you shipped end to end. Cover the user problem, your decisions, what you measured and what you would change.
• A disagreement with a teammate. Show how you made the decision on evidence and kept the relationship.
• Why this company? Connect its product and engineering problems to the work you want to do next.

Structures and sample answers for the common questions are in our software engineer behavioral answers guide.

A three-week prep plan

1. Week 1: practical coding: build small features against an API, parse and transform data, and write tests, in the language you will interview in.
2. Week 2: system design for the company's domain, plus two behavioral stories about shipping and fixing something under pressure.
3. Week 3: timed mixed problems, a mock interview every other day, and research into the product and its engineering blog.

For practice lists, use LeetCode company-tagged questions and the NeetCode 150 roadmap; for design rounds, read system design building blocks; and compare the practical style of Stripe.

Where CoPilot Interview fits

Most of a Toast loop is spoken: you explain an approach, defend a trade-off and talk through your past work. CoPilot Interview is an AI interview assistant whose free AI mock interview builds technical and behavioral questions from your résumé and the job description, reads them aloud and scores each spoken answer out of ten, so you can rehearse the explanation as well as the code. The free plan gives 15 minutes a day of live help in sessions of up to 15 minutes, with AI mock interviews included. Online assessments and many coding rounds forbid outside help, so practice beforehand and follow your employer's rules on the day.

Disclosure: CoPilot Interview is our product, so weigh what we say about it accordingly.

Frequently asked questions

What programming language should I use in a Toast interview?

Kotlin and Java dominate Toast's Android and back-end work, with React on the web. Live coding rounds generally let you choose, but Android roles expect fluent Kotlin.

Does Toast send an online assessment?

Most experienced-hire candidates describe a live technical screen first, while at least one internship report describes an easy CodeSignal assessment. Ask your recruiter which applies to you.

Do I need restaurant or payments experience for Toast?

No, but it helps to understand how a restaurant works. Spend an evening learning how an order moves from a server's handheld to the kitchen, and how a card payment is authorized, settled and refunded; it gives you concrete examples in design and behavioral rounds.

How should I prepare for Toast coding questions?

Practice practical problems under time limits, build small features against an API in your interview language, and prepare one system design in Toast's domain. Explain every solution out loud, because follow-up questions about trade-offs matter as much as the first answer.

Can I use AI tools in a Toast interview?

Only if the instructions you receive say so. Online assessments and live coding rounds generally forbid outside help, and some companies now state their AI policy in the invitation. Use AI to practice beforehand, and follow your employer's rules.