[broahmed]

Hey OP, to go off what lhorie said:

1. Does the company actually know what your open source project does and how they want to fit into the company's product?

2. Agree with lhorie that an interview consisting of 4-5 sessions of 1-hour each is typical in big tech companies based on my experience. Keep in mind they're not interviewing you for your technical chops alone which your open source work has already proven; they're looking at whether you'd fit in socially (which is pretty easy in my experience: be polite even when disagreeing with the interviewer and don't come across as an axe murderer and you'll be fine).

An alternative you might consider proposing to them is for the company to hire/sponsor you to continue working on your open source project with the agreement along the lines of:

1. you'll be adding features to better fit their needs

2. you'll help them plug your project into their product as needed