If you don't think about how you will sustain an open source project, your project will not be sustainable. "Those who fail to plan, plan to fail."

Building a business model on top of my open source Sidekiq[0] project was the best decision I've ever made. That doesn't mean my approach will work for all (or even many) projects but anyone who is trying to build a popular project needs to consider: if I succeed, what will the project look like five years from now? Will you or a core team still be helping users every day?

[0]: https://sidekiq.org