Build vs. Buy: The Infrastructure Decision Most Teams Get Wrong

Build versus buy gets treated as a vendor-evaluation spreadsheet exercise. It’s actually the decision that determines whether your AI system scales with the business or collapses the first time load triples.

The question underneath the question

“Should we build our own model-serving layer?” is really asking “who owns this when it breaks at 2am, and what does it cost us if we’re wrong?” Framed that way, a lot of build-vs-buy decisions answer themselves, and not always in the direction procurement expected.

Where teams get this wrong

• Evaluating vendors on today’s traffic, not the traffic that triggered this project in the first place
• Treating integration cost as a one-time line item instead of an ongoing tax
• Skipping the exit plan: what does migrating off this vendor actually require, in a year

Decide it once, deliberately

The infrastructure decision that gets revisited every six months isn’t a decision, it’s a symptom. Make the call once, with the real constraints in front of you: expected scale, integration cost, and what you’re accountable for if the vendor’s roadmap doesn’t match yours. That’s a decision that holds.