The most expensive mistake when commissioning custom software is leaving the source code with the vendor. Four clauses for the contract.
The sentence we hear most from businesses that commissioned custom software is: "The program is ours but the code is theirs, we cannot touch it." It rarely comes from bad intent; it comes from a contract that does not say otherwise. If these four clauses are missing, the software is not yours.
1. Source code and database are delivered
At hand-over you receive not just a running application but the source code, database schema and installation document. Another developer must be able to bring the system up from that package. Test it at delivery: do you have access to the code repository?
2. Accounts are opened in the company's name
Domain, server, store developer account and third-party services are registered in your name; the vendor is given access, not the other way round. If the domain is registered to the vendor, the website is not yours.
3. Third-party dependencies are listed
Which licensed components and external services does the software use, which ones bill monthly? Without this list, a surprise invoice or a discontinued service stops you.
4. An exit plan is written
What happens when the contract ends: within how many days and in what form are code and data delivered, is there transition support? Writing this at the start protects both sides.
A small test
Ask the vendor one question: "What happens if I do not want to work with you a year from now?" If the answer is clear and can go into the contract, the rest is detail. SMB Teknoloji writes these four clauses into every contract itself.