Error building app using v5 beta

Hello! We are trying to build our app using the latest v5 beta and we are getting an error

node-pre-gyp WARN Tried to download(404):
node-pre-gyp WARN Pre-built binaries not found for fsevents@1.2.4 and electron@5.0.0-beta.3 (electron-v5.0 ABI, unknown) (falling back to source compile with node-gyp)``` 

Any suggestions would be greatly appreciated
we are using electron-builder version=20.33.2 to build it