Call with hiring manager to start went well. Great description of the company as an initial screen. Asked about comp and experience. Next step was to set up a technical screen with one of the Product leads. That call was scheduled fairly soon after the initial call and product lead was supposed to call me. I waited 15 minutes after the scheduled time, called, recruiter and was told the product lead was in another interview and they would reschedule. This got rescheduled two more times. Considering that I heard many negative things about the culture at ZScaler, I decided this was an indicator of of future things to come and bowed out of the interview process.
ZScalar has some great technology and seems to have a great vision, so it was sad this didn't pan out.