src/main/prepare-env.js

import shellEnv from 'shell-env';
import Rx from 'rxjs/Rx';

const env$ = Rx.Observable
  .fromPromise(shellEnv())
  .first()
  .do(env => {
    Object.assign(process.env, env);
  })
  .publishReplay(1);

env$.connect();

export default env$;