Own the DataModel — the scenegraph-like core of the Roblox engine

Interview for a Senior Software Engineer role on Roblox's Engine DataModel team, owning the foundational tree-like structure (analogous to a scenegraph) that underlies the entire Roblox platform, plus the C++ reflection bindings that expose it to Luau and its serialization. Expect systems-level C++ depth — memory layout, smart pointers, templates, virtual functions — and cross-device performance reasoning (desktop, mobile, console), hybrid onsite in San Mateo 3 days/week.

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What this interview tests

Systems-level C++: memory layout, smart pointers, templates, virtual functions
Core engine data structures (tree/scenegraph-like DataModel)
Cross-device performance (desktop, mobile, console constraints)
C++ reflection/codegen bindings exposing internals to a scripting API (Luau)
Serialization design for core engine state
End-to-end ownership of systems-level projects

Common question themes

Walk me through what happens at the CPU/memory level with smart pointers, templates, and virtual functions in a hot path

Tell me about a core data structure you designed or optimized in a performance-sensitive system

How do you reason about performance tradeoffs when your code must run well across desktop, mobile, and console

Describe a project you owned end-to-end, from design to shipping, that other teams then built on

Have you worked with reflection systems or codegen that expose C++ internals to a scripting layer — how did you approach correctness and performance there

How would you approach serializing a large, evolving tree-like data structure

How candidates describe it

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