Why Luau?

Rive selected Luau (pronounced "Loo-ow") as its scripting language. Luau is a fast, small, safe, and gradually typed scripting language derived from Lua 5.1, primarily developed and maintained by Roblox.

Why Luau for a Design Tool?

🚀 Performance and Size

Real-time graphics demand efficiency. Luau's highly optimized Virtual Machine (VM) ensures scripts run quickly without causing frame drops, and its small footprint is crucial for web deployment.

🔌 Embeddability

Luau is designed to be easily integrated into larger C++ applications, like the Rive Editor and its various runtimes (iOS, Android, Web, Flutter, etc.).

📝 Gradual Typing (The Key Advantage)

This is the cornerstone of the Rive scripting experience. While Luau can be written dynamically (like JavaScript or standard Lua), it supports a robust type system:

• Robustness: Types help catch errors before the animation even runs. If you try to assign a Color where a number is expected, the editor flags it immediately.

• Tooling: Rive generates Luau type definitions directly from its C++ engine APIs—paths, shapes, transforms, artboards, view models, and more. This powers accurate autocomplete (IntelliSense).

🎯 Simple Semantics

Based on Lua, the syntax is minimalist and accessible, making it easier for designers and new programmers to learn.

Luau vs Other Languages

Feature	Luau	JavaScript	Python
Type System	Gradual (optional)	Dynamic	Dynamic
Performance	Very fast	Fast	Slower
Bundle Size	~200KB	Large	N/A
Learning Curve	Easy	Medium	Easy
Rive Integration	Native	N/A	N/A

Knowledge Check

Q:What language is Luau derived from?

Q:Who primarily develops and maintains Luau?

Q:What does 'gradual typing' mean?

Ready to Start Scripting?

Now that you understand WHY Rive uses Luau, it's time to write your first script. Choose the path that fits your experience:

🌱 New to Programming?

Start here: Your First Rive Script

We'll teach you programming concepts from scratch with clear explanations and interactive exercises. No prior experience needed.

💻 Have JavaScript or After Effects Experience?

Start here: How Rive Scripts Work

Get up to speed fast with side-by-side comparisons to what you already know. Understand the Rive script structure through familiar concepts.

Both paths lead to the same place — Luau Fundamentals — so you can always reference the other track later if you want a different perspective!