Confining every Wasm module to one bounds-checked linear memory array, growable only in 64KB pages, is precisely the security property that lets Cloudflare Workers and Fastly's Compute@Edge run untrusted third-party code from thousands of customers on shared hardware without process-level isolation. This same memory model is why a buggy or malicious Wasm module can corrupt its own heap but can never read or write host memory directly.