Merge is full of incredibly smart, driven, supportive, and low-ego people. It is a fantastic place to work on difficult problems with incredibly sharp people, and as an engineer you will be given a lot of autonomy to work on and solve novel and category-defining problems.
It's fair to say Merge is the premium product and market leader in the unified API space, and will almost certainly stay that way with the caliber of people that make up the company.
Cons
Work culture is fully in-office, which is not for everyone
The hours are somewhat long for tech. The company is still being built (which people are excited and energized by), but it's not a place to rest and vest
The people make this place what it is! Super smart, supportive, inspiring, and fun to be around! I am constantly learning from everyone around me here. We all work hard together
Cons
Not really a con for me, but this is a startup and we are full in person so we do work hard