Yes. Scalability involves multiple aspects:

1. Website Load Times: Needle uses best practices for the modern web and modern formats, like compressed glTF and progresssive loading, to optimize load times and rendering performance. This means that many users can simultaneously access websites made with Needle, same as other static websites. Using a CDN like Needle Cloud improves load times for globally distributed users as well.
2. Rendering Performance: Performance depends on scene complexity, target hardware, and optimizations. Needle builds on Three.js, benefiting from its performance characteristics. Needle does many optimizations out of the box, and you can additionally optimize your assets within Unity or Blender (reducing triangle count, draw calls, texture sizes) if needed.
3. Networking and Multiplayer: Needle’s built-in networking uses WebRTC (PeerJS), which is suitable for shared sessions with ~16-32 concurrent users, depending on scene complexity and server performance. For larger-scale concurrency (hundreds/thousands of users), you would typically need a dedicated server architecture or integrate with third-party scalable networking solutions. Needle’s networking components might serve as a starting point and you can later switch to solutions for massive-scale scenarios if needed.
4. Backend Scalability: If your application relies heavily on server-side code, the scalability of that backend infrastructure is a separate but critical factor for handling many users. This depends on your backend technology and architecture. For example, using serverless functions or microservices can help scale your backend to handle many concurrent users.