Question 1
Difficulty: easy
Walk me through how you would build a new gameplay feature from idea to release.
Sample answer
I usually start by clarifying the player problem the feature is meant to solve. Before writing code, I want to understand the gameplay goal, success metrics, technical constraints, and how the feature fits into the overall experience. From there, I break the work into a small design spec, identify dependencies, and build the simplest playable version first. I like to prototype early so we can validate the fun factor before investing in polish. After that, I add the supporting systems, integrate with UI, audio, and animations, and test edge cases thoroughly. I also try to keep the code modular so the feature can be adjusted without touching half the project. Before release, I work closely with QA and designers, review performance, and make sure the feature is stable across target platforms. My goal is always to ship something that feels good to play, not just something that technically works.
Question 2
Difficulty: medium
How do you optimize a game when frame rate starts dropping in a scene with lots of objects on screen?
Sample answer
My first step is to measure instead of guessing. I’d profile the scene to find whether the bottleneck is CPU, GPU, memory, or draw calls, because the fix depends on where the time is being spent. If it’s CPU-heavy, I look at update loops, physics, AI, and unnecessary per-frame calculations. If it’s GPU-heavy, I check shader cost, overdraw, lighting, particle counts, and texture sizes. For object-heavy scenes, batching, culling, pooling, and LOD systems can make a big difference. I also look for hidden costs like allocations causing garbage collection spikes or expensive script callbacks firing too often. I like to make changes one at a time and reprofile after each adjustment so I know what actually helped. The key is balancing performance with visual quality, because the player should feel smoothness first, not notice the technical tradeoff behind it.
Question 3
Difficulty: medium
Describe a time you disagreed with a designer or artist about a feature. How did you handle it?
Sample answer
I’ve found that disagreements are usually about priorities, not personalities. In one project, a designer wanted a feature to be highly dynamic with lots of real-time calculations, while I was concerned it would hurt performance on lower-end devices. Instead of saying no outright, I asked what the player experience needed to be and what parts were truly essential. Then I put together a quick prototype showing both the original approach and a lighter version with similar feel but lower cost. That made the tradeoffs much easier to discuss. We ended up keeping the core behavior and simplifying some of the visual logic, which preserved the gameplay while making the feature viable. I think the best way to handle these situations is to stay respectful, use data when possible, and focus the conversation on the player and the product. When everyone has the same goal, it becomes much easier to find a solution that works.
Question 4
Difficulty: hard
How do you structure code in a game so it stays maintainable as the project grows?
Sample answer
I try to keep gameplay systems modular and responsibility-focused. That means avoiding giant classes that do everything and instead separating input, state, rendering, data, and progression logic where possible. I prefer clear interfaces between systems so changes in one area don’t ripple everywhere else. For example, a combat system should not also be handling inventory UI or save logic. I also pay attention to naming, directory structure, and how data is stored, because those things matter a lot once a team grows. For reusable behavior, I like composition over inheritance when it makes sense, since it tends to stay more flexible. I also document important workflows and patterns so other developers can work in the codebase without reverse-engineering it. Just as important, I leave room for testing and debugging by building in logs, debug tools, and well-defined state transitions. Good structure saves time later, especially when the project gets bigger and deadlines get tighter.
Question 5
Difficulty: medium
What is your approach to debugging a bug that only appears intermittently during gameplay?
Sample answer
Intermittent bugs can be frustrating, so I try to make the problem reproducible before I try to fix it. I’ll start by narrowing down the conditions: platform, build type, timing, input sequence, state, and any recent code changes. If I can’t reproduce it easily, I add targeted logging or temporary debug tools to capture state right before the failure happens. I also look for timing-related issues, race conditions, null references, and order-of-execution problems, since those are common sources of bugs that seem random. When possible, I compare good runs with bad runs to spot patterns. Once I find the trigger, I make the smallest fix I can, then test nearby scenarios to make sure I didn’t create a new issue. I also like to ask whether the bug points to a deeper system weakness, because a good fix often includes a safeguard, not just a patch. The end goal is to make the issue understandable, repeatable, and preventable.
Question 6
Difficulty: hard
How do you decide whether to use an existing engine feature or build a custom system?
Sample answer
I decide based on fit, cost, and long-term control. If the engine already provides a stable feature that meets the design needs and performs well, I usually prefer using it because it saves time and reduces risk. But if the feature is too limiting, hard to extend, or doesn’t fit the game’s specific requirements, I’ll consider a custom solution. I also think about team experience and maintenance. A custom system might be powerful, but if only one person can support it, that becomes a risk later. I like to prototype both the built-in and custom approach when the choice is unclear, then compare implementation complexity, performance, and flexibility. Sometimes the right answer is a hybrid, where the engine handles the base layer and custom code adds the unique gameplay logic. My goal is not to build everything from scratch; it’s to choose the option that gives the game the best chance of shipping well and staying stable.
Question 7
Difficulty: easy
Tell me about a time you had to work under a tight deadline. How did you prioritize your work?
Sample answer
Under a tight deadline, I focus on what moves the game forward most and what can safely wait. In one sprint with a hard milestone, I first listed the tasks by player impact, dependencies, and risk. I made sure the core loop and any blocking bugs were handled before spending time on polish. I also communicated early with the team about what could realistically be done and where we might need scope cuts. That helped avoid surprises later. For my own work, I broke tasks into very small pieces so I could keep delivering progress daily instead of waiting for one big finish. I also reserved time for testing, because rushing without verification usually creates more work. When deadlines are tight, I think it’s important to stay calm, keep the feature set focused, and make deliberate tradeoffs. Shipping a clean, reliable core experience is usually better than trying to do everything and risking the entire milestone.
Question 8
Difficulty: medium
How would you implement a save system for a game with multiple levels and player progression?
Sample answer
I’d start by identifying exactly what needs to persist: level completion, unlocked abilities, inventory, settings, checkpoints, and any meta progression. Then I’d design a save data structure that is versioned, so we can support future updates without breaking existing saves. I usually separate runtime state from serialized data, because not everything in memory should be written directly to disk. For example, references and temporary values should be rebuilt at load time rather than stored as-is. I’d also think about when the game saves: manual save, autosave, checkpoints, and shutdown. Reliability matters, so I’d use a safe write process to avoid corruption if the game closes unexpectedly. I’d test edge cases like partial progress, upgraded content, and loading across different scenes or platforms. If the game uses multiple systems, I’d make sure each one exposes clean save/load hooks. A good save system should feel invisible to the player and dependable across the whole game.
Question 9
Difficulty: easy
What steps do you take to make your code easy for other developers to work with?
Sample answer
I try to write code with the next developer in mind, not just myself. That starts with clear naming and small functions that do one thing well. I avoid clever shortcuts if a straightforward solution is easier to understand and maintain. I also keep related logic together and separate unrelated responsibilities so people can find what they need quickly. When I add something important, I usually include concise comments explaining why a decision was made, especially if there’s a tradeoff or workaround involved. I also make sure the feature is easy to test and debug, because that saves the team time later. When appropriate, I’ll provide example usage or a short note in the project documentation so others don’t have to guess how the system works. I think good code is collaborative code. If another developer can pick it up, extend it, and trust it without a long explanation, that’s a strong sign the implementation was done well.
Question 10
Difficulty: hard
If a feature you built is fun in prototype form but too expensive to run in the full game, what would you do?
Sample answer
That situation comes up a lot, and I’d treat it as a design and engineering problem together. First, I’d identify which parts of the prototype create the fun and which parts create the cost. Often the player only needs a few key behaviors to get the same feel, so I’d look for simplifications that preserve the experience while reducing load. That might mean fewer simulated objects, less frequent updates, cached results, simpler visuals, or using approximate logic instead of exact calculations. I’d also talk with design to make sure any changes still support the intended gameplay. If needed, I’d build a second prototype focused on performance and compare it with the original. My priority would be to protect the core player experience while making the feature practical for production. I think good game development is about making smart tradeoffs, not defending an early implementation just because it was the first one that worked.
