Roblox Luau Patterns

Luau Patterns

When to Load

Load for module shapes, resource ownership, scheduling, and failure contracts. See roblox-luau-core for semantics, roblox-luau-types for types, roblox-architecture for startup.

Quick Reference

Choose a shape

• Plain functions: default for stateless transformation or validation.
• Module with private state: one explicit subsystem owner. Do not create a manager class merely to namespace functions.
• Object with metatable: multiple independent values need shared behavior and lifecycle.
• Existing library abstraction: follow it when the project already uses it consistently. Do not add Promise, signal, cleanup, or framework dependencies for one call site.

Constructors use ., instance methods use :, and mutable fields belong on the instance, not the class table.

Make ownership visible

Signal connections, instances, and tasks need cleanup owners. Disconnect/cancel at teardown. Export typed custom signal payloads (Signal<T...>).

Configure before parenting to hide partial state. Parent earlier only when ancestry is required; explain why. This does not guarantee replication ordering.

Preserve failure semantics

luauCopy code
local ok, value = pcall(dataStore.GetAsync, dataStore, key)
if not ok then
    return nil, `read failed: {value}`
end
return value, nil -- value may legitimately be nil

Do not collapse "call succeeded and returned nil" into "call failed." Retry only when the domain operation is safe to repeat. Persistence, HTTP, purchases, and remotes belong to their domain skills.

Naming and return contracts

Practitioner conventions: mark yielding functions Async, keep return counts consistent, and prefer named module exports. Respect existing project contracts; details in full.md.

Schedule deliberately

Use task.defer, task.spawn, task.delay, and task.cancel deliberately. Avoid legacy wait() and unjustified polling. Prefer a real state-change signal; otherwise choose and measure an explicit cadence.

Review

Clear owner, narrow public API, no circular require, no accidental concurrent startup, success and missing-data states remain distinct, connections/tasks cleaned up, client input routed to roblox-networking.

Details: references/full.md