Hi Tam,
If you're simply looking to get an app up and running that would run exclusively within and be accessed through your own network (like SSO), Heroku probably would not be a good fit.
You can do local development using tools like Foreman (
https://devcenter.heroku.com/article...y-with-foreman) but this is intended to ensure that the environment you use to develop and debug apps is similar to your production environment on Heroku. Since you can't use Heroku as your production environment in your use case, using Heroku probably wouldn't add any benefit for you.