Begin with proven experience, germany software development agency not the size of the portfolio. Request two or three engagements that match your domain and your stack, and then ask specifically whether those engineers are still with the company. A solid partner is happy to connect you with the tech lead. Evasive answers at this stage generally mean you are talking to a reseller.

The contract deserves a slower read than the pitch. Three sections matter more than the rest: ownership of the code, non-disclosure, and notice periods and handover. Everything produced should transfer to you on payment, bespoke software cost along with documentation, pipelines and deployment scripts. Be careful with any clause that leaves so-called reusable libraries outside the transfer, as that is often exactly the piece that locks you in.

Ask how they estimate. A credible estimate is accompanied by a written set of assumptions, a breakdown by feature or module and a best case and a worst case. A fixed-bid deal only makes sense when the requirements are stable and documented; in any other case the supplier pads the number and php web portal development you pay for it anyway. Hourly billing moves the risk back to the client, kotlin app development company so it demands a sprint cadence, demos and a budget cap.

The delivery process matters more than the number of developers. Establish what happens when the scope changes, who signs off on a feature and what the QA setup looks like. A mature team should be able to demonstrate a working build every one or two weeks. Acceptance criteria in writing are your only real protection against an argument at delivery time.

Last, consider the end of the engagement before it becomes urgent. Require that the code repository stays under your account from day one, and that documentation is written as you go rather than left to the end. A vendor with nothing to hide accepts it without argument; resistance at this point tells you a great deal.