In a team of ten, culture is osmosis. In a team of a hundred, it's whatever your systems quietly reward. Scaling means writing down what used to be understood.
Make the implicit explicit
The values that got you here need to survive people who never met the founders. That means encoding them into how you hire, promote, and give feedback — not just a poster in the kitchen.
Hire and promote against the behaviour you actually want
Give managers the language to name culture in reviews
Kill the perks nobody uses; keep the rituals that connect people
Culture doesn't dilute because you grew. It dilutes because you stopped being deliberate about it.