Using the latest dev, I'm unable to run code generated by protoc when it's compiled to WASM / WASI.

Error: failed to run main module `example.wasm`

Caused by:
    0: failed to instantiate "example.wasm"
    1: unknown import: `env::sync/atomic.StoreUint32` has not been defined
make: *** [run] Error 1

A full reproduction can be found here: https://github.com/kyleconroy/tinygo-protoc. You'll need to have wasmtime installed to run the example.wasm file.