solid-impl-state-patterns

Quick Reference

State Primitives Overview

Primitive	Import	Use Case	Access Syntax
`createSignal`	`solid-js`	Single values, primitives, toggles	`signal()` (getter function)
`createStore`	`solid-js/store`	Nested objects, arrays, complex state	`store.prop` (direct access)
`createContext`	`solid-js`	Shared state across component tree	Provider + `useContext`
`createMemo`	`solid-js`	Derived/computed values	`memo()` (getter function)
`createMutable`	`solid-js/store`	MobX/Vue migration only	`state.prop` (direct mutation)

Critical Warnings

NEVER use createEffect to synchronize derived state — ALWAYS use createMemo instead. Effects are for side effects (DOM, network, logging), not for computing values from other signals.

NEVER store signal values in variables outside tracking scopes — the variable captures a snapshot, not a reactive binding. ALWAYS call the getter function where you need the current value.