Fundamentals

Overview

Katalyst is built around three simple ideas:

1. Proxy-wrapped Instances — each New(className) returns a proxy that forwards reads/writes to a real Instance while adding reactive wiring.
2. Reactive State — a tiny State primitive with get, set, and onChange that batches updates.
3. Declarative children — Children props accept arrays, nested fragments, functions, or State-backed arrays; Katalyst diffs and attaches/detaches Instances.

Architecture overview

• New constructs a real Instance and returns a lightweight proxy with metamethods for property access, assignment, calling, and equality.
• Property assignment accepts State objects and functions (computed props). State subscriptions update the underlying Instance when values change.
• Children are handled by a small internal function that keeps a weak-keyed cache of attached children per parent and removes children that are no longer used.

Why this design?

• Minimalism: single-file runtime and a tiny API make the framework easy to audit and embed.
• Interoperability: because Katalyst operates with real Instances, existing Roblox APIs (TweenService, etc.) continue to work seamlessly.