Custom software development deliverables are the tangible outputs a client receives at the end of a software development project. The specific deliverables depend on the project's scope and requirements but may include functional and technical specifications, software design documentation, source code, testing and quality assurance documentation, user manuals, maintenance and support documentation, and installation packages. Defining deliverables at the project's outset ensures the client understands what they will receive, avoiding misunderstandings and ensuring the project's successful completion.