Build vs buy
Build vs buy is the decision to develop a capability in-house or acquire it from a vendor or SaaS product. The answer turns on whether the capability is your real differentiation, the total cost over its realistic lifetime, the time-to-market, and the maintenance load you can sustain afterwards.
Build vs buy is a framing, not a formula. Build when the capability is part of what makes your product distinct and you can fund it for years. Buy when the capability is table-stakes plumbing that a vendor already runs better than you ever will.
Four things decide it in practice. First, differentiation: if customers will not notice the difference, buying is usually right. Second, total cost of ownership over the realistic lifetime — not the first quarter, but five years of upgrades, on-call, and rewrites — which is almost always higher for build than the initial sticker suggests. Third, time-to-market: building is slower than the optimistic estimate, and the gap matters when the window is short. Fourth, who maintains it the day after launch, which is where many in-house builds quietly rot.
The common mistake is treating build as "free" because the team is already hired. The opportunity cost of what those engineers are not building is the part that gets skipped, and it is usually the most expensive line on the page. If the answer is build, a dedicated development team is often cheaper than hiring locally once time-to-hire and ramp are included. If the answer is buy, managed services keep the maintenance load off your roadmap.
