Mozilla, Fastly and others have started work on a new standard interface for WASM to interact with system calls, they're calling it WASI, the WebAssembly System Interface.

https://hacks.mozilla.org/2019/03/standardizing-wasi-a-webassembly-system-interface/

I think we should consider supporting this in the Go WASM architecture, possibly under a new OS (GOOS=WASI).

This issue should track the development of such an effort.

Mozilla have invited interested parties to join the #wasi channel on the Mozilla IRC server (https://wiki.mozilla.org/IRC).