What is SLua?
SLua is a new scripting option in Second Life built on Luau (a modern variant of Lua). It brings many advanced programming tools — like more powerful data structures, event handling, timers, coroutines, and a more flexible, familiar syntax — while remaining compatible with what you know from the old scripting language (LSL).
Why is this important now?
Because SLua uses memory and CPU more efficiently (~ 50 % less memory than LSL/Mono) and scripts run faster. That means objects and experiences made with SLua can be more complex and robust, without overstressing the simulator.
What new capabilities do creators get?
- Native tables/data structures (so you can store key-value data or arrays easily) instead of juggling multiple lists.
- Better event handling: you can register multiple event handlers or dynamically manage them, making scripts more modular and easier to maintain.
- Timers and asynchronous operations (coroutines) — great for animations, timed interactions, web requests, or sequences of actions.
- Cleaner, more modern syntax — if you’re familiar with Lua, Python or JavaScript, you’ll find SLua easier to read and write.
Does SLua replace LSL?
Not — at least not immediately. The existing LSL scripting will continue to work. SLua is offered as a modern alternative, not a forced replacement. In fact, during beta, SLua-written scripts only run in “SLua Beta” regions, while standard regions keep using LSL.
Over time, the backend VM that runs scripts (currently “Mono” for many LSL scripts) is intended to be replaced by a SLua-based VM. But that doesn’t necessarily mean LSL will disappear — it may remain for compatibility.
Should you care as a casual user or content consumer?
If you mainly use existing content — probably not immediately. But creators, scripters, or developers will likely begin offering richer, smoother, more dynamic experiences. Over time, SLua could expand the creativity and technical possibilities in Second Life significantly.