Agile Frameworks & Tools for Startups - Scrum, Kanban, etc.?

Coming from enterprise tech consulting, Scrum was the most popular agile framework - also a lot of buzz around Scaled Agile Framework (SAFe). What are startups using? Considering the popularity of Trello, I'm assuming it's a lot of Kanban. Is Scrum too heavy a process for you all? Are you establishing cadence with Kanban? Looking for general feedback on popularity/success using different frameworks & tools. Any Trello alternatives that people like for Scrum?