Top 3 Build versus buy Interview Questions
Browse 3 real-world technical and behavioral interview questions about Build versus buy. Review scenarios, edge cases, and architectural best practices.
Build or buy an internal developer platform: build the total-cost comparison.
Compare total cost of ownership like for like. Buying still needs a platform team, building never ends at launch, and a later launch delays benefit. On illustrative figures for 300 engineers over three years, buying costs 1,595k against 2,775k to build, and building wins at steady state only above about 900 engineers.
Your team wants to replace an expensive integration vendor with an in-house build. Do you approve it?
Not as first proposed. Approve a short discovery and a renegotiation, then a phased migration only if the full cost of owning every integration, including an on-call rota, connector upkeep and dual running, beats the renegotiated fee, or a non-cost reason such as roadmap control justifies paying more.
How do you decide whether to build a capability in-house or buy it?
Build what your users pay you for and buy the rest, correcting that heuristic for switching cost and data gravity. The comparison people get wrong is licence fee versus zero, when it is really licence fee versus salaries, on-call and opportunity cost for as long as the system lives.