精彩长文推荐。

In a project I’ve been playing around with recently, we’ve encountered the dilemma where you want to make it easy for users to write their own application logic using the system but at the same time want to keep that logic decoupled from the implementation details of whatever platform the application is running on.

If you’ve been programming for any amount of time your immediate reaction is probably “why bother mentioning this, doesn’t it just fall out of good library design?”, and normally I would totally agree with you, except I forgot to mention a couple of important details…

1. People need to be able to upload new code while the system is still running
2. This application will be interacting with the real world (think robots and automation), and we really don’t want a crash in user-provided code to make the entire system stop responding

http://adventures.michaelfbryan.com/posts/wasm-as-a-platform-for-abstraction/