- API Utilization – Working with RESTful endpoints, handling asynchronous requests, and parsing JSON responses.
- Code Quality and Readability – Writing modular, self-documenting code with clear variable naming and robust error handling.
- Advanced concepts (less common) – Optimizing time and space complexity for large datasets, and managing concurrent API calls.
Example scenarios:
- Parsing a raw log file of customer chat messages to extract metadata and format it for a database write.
- Fetching data from a paginated endpoint and merging it with a local dataset while handling network timeouts.
System and API Design
Our system design interviews focus on your ability to architect scalable distributed systems and design clean, intuitive APIs. We want to see how you approach ambiguity, define system requirements, and make pragmatic architectural trade-offs.
You will be asked to design a system or a specific set of APIs that support a product feature. You should start by clarifying requirements, defining the data model, sketching out the high-level architecture, and then diving deeper into specific bottlenecks or scaling challenges.
Be ready to go over:
- API Interface Design – Designing clean, intuitive, and consistent endpoint contracts between the frontend and backend.
- Data Modeling and Storage – Choosing the right database technology (SQL vs. NoSQL) and designing schema relationships for fast lookups.
- Scalability and Reliability – Implementing caching, load balancing, rate limiting, and message queues to handle high traffic spikes.
- Advanced concepts (less common) – Real-time synchronization protocols like WebSockets or gRPC for instant message delivery.
Example scenarios:
- Designing a URL shortener service that can scale to handle millions of redirects per day.
- Designing the backend architecture and API payloads to support a live-updating dashboard for customer support agents.
Project and Topic Presentations
One of the most distinctive aspects of the Gladly interview process is the presentation loop. We believe that great engineers are also great communicators. You will be asked to deliver two separate presentations: one focusing on a past technical project you are proud of, and another on a topic of your choice.
The past-project presentation is a deep dive into your technical leadership and problem-solving abilities. You will walk a panel of engineers through a project you built, explaining the architecture, the challenges you faced, and the decisions you made. The personal topic presentation is your opportunity to teach the team something new—it does not have to be highly technical, but it must showcase your ability to structure a narrative and engage an audience.
Be ready to go over:
- Technical Narrative Structure – Clearly defining the problem, the constraints, the solution, and the ultimate outcome of your project.
- Architectural Deep Dives – Explaining your technical choices, the trade-offs you considered, and what you would do differently in hindsight.
- Audience Engagement – Delivering a polished, clear presentation and handling live Q&A sessions with confidence.
- Advanced concepts (less common) – Explaining complex technical systems to a cross-functional audience that includes product and design partners.
Example scenarios:
- Presenting the migration of a legacy monolithic service to a microservices architecture, detailing the zero-downtime strategy.
- Giving a 20-minute presentation on a personal hobby, a unique technology, or a productivity framework that you are passionate about.
Product Demo and Collaborative Problem Solving
At Gladly, engineering does not happen in a vacuum. We work closely with product managers, designers, and customers to build a product that solves real pain points. The product demo and collaborative session evaluate how you think about product UX, user workflows, and collaborative design.
During this session, you may walk through a product demo or collaborate on a feature concept. The goal is to see how you translate user needs into technical requirements, how you give and receive feedback, and how you brainstorm solutions with others.
Be ready to go over:
- User-Centric Design – Understanding the target user's pain points and design choices that improve their workflow.
- Collaborative Brainstorming – Building on top of others' ideas, asking clarifying questions, and constructively challenging assumptions.
- Feature Prioritization – Balancing technical feasibility, development effort, and user value when planning a feature.
Example scenarios:
- Reviewing a mock-up of a new customer timeline feature and discussing the API endpoints and data structures needed to support it.
- Participating in a collaborative session to brainstorm how to make the agent search experience faster and more intuitive.
