The moment a growing company decides it’s finally time to build a real internal security function, the instinct is to think about headcount: how many people, how fast. The sequence those people arrive in matters far more than the total number.
The first one or two hires should be a security engineer or generalist who can lay the actual foundation — identity and access management, centralized logging, and endpoint protection. Nothing else in the roadmap works without that groundwork in place.
Hires three and four typically split between detection and response — someone who can actually watch what the foundational tooling is now producing — and a GRC-minded hire who starts building policy, documentation, and the compliance groundwork that audits and customers will eventually ask for.
By hires five and six, the right move is to specialize based on what’s actually causing pain — cloud security if your infrastructure is the risk, application security if your product is customer-facing, or a lead/vCISO to set strategy if the team has outgrown ad-hoc decision making. Hiring generically past this point is how teams end up with five people who can all do the same thing and nobody who can do the next thing you need.