Stay far away.
3 onsite interviews, 2 phone interviews, multiple phone calls with HR. Overall met with ~10 people
It was 3 months of a highly prolonged, non-transparent, and disorganized process. At one point, after 3 rounds of interviews, the HR contact asked me to forward her my resume again because they had lost it.
They would often go cold for weeks and resurface with something like "XX really enjoyed speaking with you -- when are you free to meet with XX?" Eventually, during my last onsite interview, they apologized for how tedious/unclear of an experience it had been and said they finally planned to moved forward.
One week later the HR contact called to say they would be extending an offer, and discussed salary and start date.
2 weeks after that, she called again to say that due to headcount / budget restraints they'd be in touch at some point next quarter.
Terrible, terrible form to give a verbal offer and retract. Almost completely unheard of in any professional setting -- whether you're a startup or massive company.