Custom software development companies manage security and quality through a variety of practices. They work with clients to implement security measures tailored to the clients’ risk tolerance and requirements such as encryption, secure coding techniques, and regular security audits. Quality assurance is achieved through rigorous testing phases, including unit tests, integration tests, and user acceptance tests. Additionally, they work with clients to manage clients’ compliance with industry standards and regulations, which can include continuous monitoring and working with clients to make sure that software is updated and patched to address vulnerabilities.