Build your best UI.

Fusion is a modern reactive UI library, built specifically for Roblox and Luau.

Build your UI with a declarative syntax that's easy to read and write.
Plug in live data with simple, flexible, truly reactive state management.
Deliver a fast, smooth experience to everyone - on mobile, console, PC or in VR.

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Declarative UI syntax

Fusion provides a natural, easy to read syntax, so you can focus on what your UI should look like, without worrying about the implementation.

Focus on the properties and children in your UI, not verbose APIs.

return New "ScreenGui" {
    Parent = Players.LocalPlayer.PlayerGui,

    [Children] = New "TextButton" {
        Position = UDim2.fromScale(.5, .5)
        AnchorPoint = Vector2.new(.5, .5),
        Size = UDim2.fromOffset(200, 50),

        Text = "Fusion is fun :)",

        [OnEvent "Activated"] = function()
            print("Clicked!")
        end
    }
}

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Reactive state management

Fluidly write all your calculations, and they'll be automatically run as your variables change.

Fusion accelerates and optimises all of your computations for you.

local numCoins = State(10)

local doubleCoins = Computed(function()
    return numCoins:get() * 2
end)

local coinsMessage = Computed(function()
    return "You have " .. numCoins:get() .. " coins."
end)

return New "TextLabel" {
    Text = coinsMessage
}

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Animate everything

Bring your UI to life with the simplest, most universal animation tools of any Roblox library. Access tweens and springs with one line of code.

Animate anything instantly, no refactoring or performance tricks required.

local playerCount = State(100)
local position = State(UDim2.new(0, 0, 0, 0))

local smoothCount = Tween(playerCount, TweenInfo.new(0.5))

return New "TextLabel" {
    Position = Spring(position, 25, 0.2),

    Text = Computed(function()
        return "Players online: " .. math.floor(smoothCount:get())
    end)
}

Fusion is built with performance in mind, from idea to implementation.

From top-end desktop PCs to budget phones from years ago, Fusion delivers an exceptionally light, fluid experience as standard.

Build your most beautiful, bold, animated interfaces with confidence - Fusion scales to high-refresh-rate devices and VR effortlessly.

Get up and running with Fusion in minutes.

Downloading and importing Fusion into Studio is quick, easy and 100% free.

The Fusion starter tutorials are aimed at a wide range of creators, from seasoned UI developers to novice scripters.