Roblox Staff Software Engineer Interview Questions

Behavioral Questions (15)

1. 1.Describe a time you built a feature that needed to work safely for users of different ages or trust levels. How did you think about the safety implications in your design?

   easy~3 min

   What interviewers look for

   • Shows proactive consideration of safety implications during the design phase rather than as an afterthought
   • Demonstrates understanding that different user populations require different safety controls and that one-size-fits-all approaches are insufficient
   • Exhibits collaboration with safety/policy teams and ability to balance feature functionality with safety requirements

   Likely follow-ups

   • How did you validate that your safety measures were actually effective?
   • What would you do if product requirements conflicted with safety requirements?

   Company context

   Roblox's Trust and Safety at Scale principle is critical because a large portion of the user base is under 18, requiring engineers to integrate safety, moderation, and parental controls into every product surface. The 'Respect the Community' value means engineers must consider both the developer ecosystem and user safety in every technical decision, especially given Roblox's creator-driven platform model.

2. 2.You notice that our content moderation pipeline is taking 30 seconds to process user-generated meshes, but developers expect near-instant feedback in Studio. How would you reduce this latency?

   easy~3 min

   What interviewers look for

   • Proposes async processing with immediate provisional approval for low-risk content, allowing developers to iterate while safety review continues
   • Identifies preprocessing opportunities - running lightweight safety checks client-side in Studio before upload
   • Considers caching strategies for previously-approved similar meshes to avoid redundant ML model inference
   • Discusses fallback mechanisms when fast-path moderation fails, ensuring safety isn't compromised for speed
   • Proposes developer feedback UX - showing moderation progress and estimated completion time in Studio

   Likely follow-ups

   • How would you handle the case where a mesh passes fast moderation but fails the full safety review later?
   • What metrics would you track to ensure your optimizations aren't degrading moderation quality?

   Company context

   Roblox's Trust and Safety at Scale principle requires every feature to consider user safety, especially for younger users. The Get Stuff Done value means developers need fast iteration cycles in Studio, but safety can't be compromised. This tension between speed and safety is central to Roblox's platform engineering challenges.

3. 3.We're launching a voice chat feature that needs to route audio between players in the same 3D experience across different game servers. How would you design this to support millions of concurrent conversations while keeping latency under 100ms?

   easy~3 min

   What interviewers look for

   • Proposes edge-based audio routing to minimize hops between players in the same geographic region
   • Considers spatial audio requirements where voice volume and direction depend on 3D player positions
   • Addresses cross-platform audio codec compatibility between PC, mobile, console, and VR clients
   • Incorporates real-time safety measures like profanity detection and parental controls for voice

   Likely follow-ups

   • How would you handle the case where a single popular experience has 10,000 players all in voice chat?
   • What happens when players on mobile networks experience packet loss during voice transmission?

   Company context

   Roblox's voice chat feature represents the intersection of their real-time 3D engineering and trust and safety priorities. The platform must deliver low-latency spatial audio while protecting younger users through real-time moderation, all while supporting Roblox's cross-platform client diversity from high-end PCs to budget Android phones.

4. 4.Tell me about a time you had to convince multiple engineering teams to adopt a new technical standard or practice, but you weren't their manager. How did you approach getting buy-in?

   easy~3 min

5. 5.A developer reports that their popular experience is suddenly getting 50% fewer players joining, but the game itself is running fine. Walk me through how you'd investigate this drop and what you'd check first.

   easy~3 min

6. 6.Tell me about a time you had to optimize performance for a real-time system where latency directly impacted user experience. What was causing the bottleneck and how did you approach solving it?

   medium~4 min

7. 7.We're seeing memory pressure in our Lua scripting runtime when developers create experiences with thousands of objects. Walk me through how you'd approach this problem without breaking backward compatibility for existing games.

   medium~4 min

8. 8.Our Developer Exchange program pays out millions monthly to creators. We need to build a new revenue analytics dashboard that shows creators their earnings in near real-time. How would you design this system to handle payment data for 2 million active developers?

   medium~4 min

9. 9.You're leading a cross-platform feature that needs to ship simultaneously on mobile, console, and VR, but the teams have different release cycles and quality bars. How would you coordinate this launch?

   medium~4 min

10. 10.We're considering adding a new creator monetization feature, but we need to estimate how much additional server cost it would generate. The feature lets developers sell limited-time virtual items that expire after 24 hours. How would you model the infrastructure cost?

    medium~4 min

11. 11.Walk me through a time you designed an API or system that external developers would depend on. How did you balance flexibility for developers against your own engineering constraints?

    hard~5 min

12. 12.You're tasked with implementing a spatial query system for our game server orchestration. Players need to find experiences near their friends across different game instances. How would you design this to handle 50 million concurrent users?

    hard~5 min

13. 13.We want to add collaborative editing to Roblox Studio so multiple developers can build the same experience simultaneously. How would you design this to handle conflicts when developers modify the same 3D objects or scripts at the same time?

    hard~5 min

14. 14.Describe a time you had to make a long-term technical investment that wouldn't show results for 6-12 months, but your team was under pressure to deliver short-term features. How did you handle this tension?

    hard~5 min

15. 15.Roblox wants to expand into a new geographic market where internet infrastructure is significantly less reliable than our current markets. Estimate the engineering investment needed to make our platform work well in this environment, and walk me through your reasoning.

    hard~5 min