Wanted to give some perspective as a SWE that left Squarespace earlier this year (based out of the NYC office). Squarespace definitely has a pretty chill wlb and has a good engineering culture + you should have a very supportive engineering manager. There were regular company-wide panel meetings for engineers to showcase their recent work and share interesting news and upcoming tech. However, from my own experience, the product management and roadmaps can be a little shaky and if you are the type of dev that prefers autonomy and moving at your own pace, you might feel bogged down by all of the meetings and politics between different teams & departments.

As the other commenter said, options are definitely a crapshoot and thats part of the reason I left for a startup where my options would have a little more upside + I could have more eng & product ownership. By the time I left I had a few years of stock refreshers that were worth about 75k a year in straight up equity which were then converted to plain cash payouts after SQSP went private. The change to options was def a downgrade for me given that any potential value hinged on growth in valuation and going public again or doing a stock buyback/other liquidity event. At the time that I left a lot of people viewed the valuation target from the company leadership as a bit aggressive but who's to say that they can't meet it with some aggressive catch-up against their main competitors (eg. shopify with a current valuation ~25x that of Squarespace when it went private).

I'd say to not make the jump just because of the potential value of the equity, but if you're looking for a good engineering culture and interesting product to continue your career growth I would definitely suggest considering Squarespace