Home › Introduction

Getting Started

Install Flux and build your first reactive UI component in Roblox.

Installation

Wally (Recommended)

Add Flux to [dependencies] in wally.toml and run wally install:

[dependencies]
Flux = "kohltastrophe/flux@0.4.0"

Flux installs as a shared dependency in Packages, available to both client and server scripts.

GitHub Releases (.rbxm)

1. Download the latest Flux.rbxm from GitHub Releases.
2. Drag Flux.rbxm into Roblox Studio and place the Flux module inside ReplicatedStorage.

File Sync (Rojo)

Copy or submodule the repository's src/ directory into your Rojo tree and require it directly.

Your First App

Create a LocalScript in StarterPlayerScripts:

--!strict
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local Flux = require(ReplicatedStorage.Flux)
local new = Flux.new

local function CounterApp()
	local count = Flux.signal(0)

	return new "ScreenGui" {
		Name = "FluxCounterApp",
		ResetOnSpawn = false,
		Parent = Players.LocalPlayer:WaitForChild("PlayerGui"),

		new "TextButton" {
			AnchorPoint = Vector2.new(0.5, 0.5),
			Position = UDim2.fromScale(0.5, 0.5),
			Size = UDim2.fromOffset(250, 80),
			BackgroundColor3 = Color3.fromRGB(30, 30, 35),
			TextColor3 = Color3.fromRGB(255, 255, 255),
			TextSize = 24,

			Text = function()
				return `Clicks: {count()}`
			end,

			Activated = function()
				count(count() + 1)
			end,
		},
	}
end

CounterApp()

Press Play (F5). Clicking the button increments the counter, updating only the button's Text property on the next frame.

How It Works

1. Flux.signal(0) creates a typed reactive signal (State<number>) holding 0.
2. count() reads the current value and subscribes the Text binding. Calling count(count() + 1) writes a new value.
3. Text = function() ... end binds a getter to Text. It sets "Clicks: 0" immediately when created, then batches future updates once per frame (PreRender).
4. Activated = function() ... end connects the callback to TextButton.Activated.

You can also create untyped nodes with Flux(0) and use arithmetic or string interpolation directly on the node:

local count = Flux(0)
-- Inside TextButton:
Text = function() return `Clicks: {count}` end,
Activated = function() count(count + 1) end,

See Signals for when to use typed Flux.signal versus terse Flux(0).

Coming from 0.2.0

If you are upgrading an existing project from 0.2.0 to 0.3.0, update these renamed or consolidated APIs:

0.2.0	0.3.0	Notes
_ATTR, _TAG, _EVENT, _REF, _CLEAN	__ATTR, __TAG, __EVENT, __REF, __CLEAN	Table directives now use a double underscore (__EVENT.__ATTR, __EVENT.__TAG).
Flux.attr, Flux.tag, Flux.event, Flux.ref, Flux.onDestroy	_attr_Name, _tag_Name, _Prop, __attr_Name, __tag_Name	One-off directive helpers are replaced by inline prefix keys and __* directive tables.
Flux.listen(inst, prop)	Flux.property(inst, key)	Also supports "$Attr" / "_attr_Attr" and "#Tag" / "_tag_Tag" (or Flux(inst, key)).
Flux(fn, true)	Flux.effect(fn)	Flux() only constructs signals (Flux(v)), computeds (Flux(fn)), and property nodes (Flux(inst, key)).
Flux.on(deps, fn)	Flux.effect(Flux.on(deps, fn))	Flux.on now returns a tracked effect callback rather than a standalone listener.
Flux.wrap / Flux.props	Flux.split(props, ...)	Split custom component props from pass-through instance props. Nested tables in Flux.new and Flux.edit flatten automatically.
Flux.default	Flux.otherwise	Default branch key in Flux.switch.
Flux.safe + Flux.catch	Flux.safe(tryFn, catchFn)	Combined into a single error-boundary helper.
Flux.clean(...)	Flux.dispose(...)	Immediately tears down any Cleanable (use Flux.cleanup(fn) to register on the active owner).
Flux.viewport, Flux.scale, Flux.safeArea	Flux.Responsive.*	Accessed via Flux.Responsive.viewport, scale, breakpoint, displaySize, platform, input, etc.
Flux.pointIn, Flux.sunk, Flux.exclusive	Flux.Interact.*	Accessed via Flux.Interact.pointIn, sunk, covered, hover, press, selected, and focused.
Flux.Color.contrastText, spin	Flux.Color.readable, rotateHue	Renamed on the Oklab color utility namespace.

Next Steps

• Signals: Hold and update reactive state.
• Computeds: Derive and cache values from other state.
• Effects: Run side effects on frame flushes.
• Scopes: Group instances and reactions under a single :Destroy().
• Components: Build reusable UI functions and split props with Flux.split.
• Creation: Explore Flux.new, two-way Flux.model bindings, and directives.