Use when assigning Roblox feature ownership, code location, dependencies, startup, or client-server boundaries without imposing a framework.

Roblox Architecture When to Load Load when code ownership is unclear, a feature crosses client and server, startup order matters, or a module is being split. Do not load merely to add a service/controller framework to a small feature. Quick Reference Start from one owner For each behavior, name: authoritative state and who may mutate it; public operations and callers; Roblox instances, connections, and tasks it owns; persistence or network boundary; startup and teardown conditions. Group by feature when that keeps one change together. Split server, client, and shared code only where the runtime boundary requires it. Shared code contains no secrets or authoritative mutable state because replicated code is readable by clients. Use the smallest dependency shape Direct module calls are the default for a stable dependency. Use a signal when one publisher has genuinely independent observers. Do not add a global event bus, dependency container, manager class, or Init / Start ceremony to hide an ordinary dependency. Keep module top level work cheap and non yielding. A small bootstrap owns only startup that truly needs ordering. Call ordered startup sequentially and fail visibly. Concurrency must be explicit and safe, not automatic task.spawn around every module. Bound WaitForChild when a dependency arrives through replication and handle timeout. An unbounded wait turns a missing instance into a silent startup hang. Enforce runtime authority The client presents input and prediction. The server validates and decides authoritative outcomes. Remotes are APIs with types, bounds, state, ownership, abuse controls, and failure behavior. Route implementation details to roblox networking and roblox security . Split only for evidence Split when there is a separate lifecycle or authority boundary, a distinct persistence contract, an independently testable pure core, or unrelated reasons to change. Do not split for folder symmetry or speculative reuse. Review One canonical owner per mutation, no hidden startup yield or replicated trust decision, explicit cleanup, and the smallest traceable structure. For tag driven behavior, use tags for discovery, attributes for configuration, and one owner for attach/remove cleanup. Detailed layouts, dependency rules, and startup examples: [references/full.md](references/full.md)

roblox-architecture