Proofpoint

Nice people, no drama, reasonable hours (but very little flexibility).

Engineering leadership lacks experience and is struggling with cloud technology, repeating every common engineering mistake. Sadly, the culture is not open to improving by listening to external experience.

If you are an established expert who has already successfully built larger systems than here you'll be very frustrated at Proofpoint as your input is routinely ignored. The culture is strictly hierarchical so unless you land position with an architect title you will be treated as an entry-level coder.

If you want to hire experienced A team players you must give them the responsibility and authority to deliver.