Output looks wrong to me.

[prographo]

Negative numbers?

> var randomNumber = require("random-number-csprng");
undefined
> randomNumber(0, 4294967295).then( r => { console.log(r) } )
Promise [Object] {
  _bitField: 0,
  _fulfillmentHandler0: undefined,
  _rejectionHandler0: undefined,
  _promise0: undefined,
  _receiver0: undefined }
> -1800540632
> randomNumber(0, 4294967295).then( r => { console.log(r) } )
Promise [Object] {
  _bitField: 0,
  _fulfillmentHandler0: undefined,
  _rejectionHandler0: undefined,
  _promise0: undefined,
  _receiver0: undefined }
> -269205720

[mlc]

this looks to me like it might be a duplicate of #4.