Senior C++ Developer

We are looking for a Senior C++ Engineer with strong low-level programming and security expertise to identify and remediate vulnerabilities in a large-scale, mature healthcare product. The ideal candidate has hands-on experience with legacy C++ codebases, memory safety (pointers, buffer overflows, memory corruption), multithreading, secure coding, and strong debugging/troubleshooting skills.  Location - Bulgaria, Poland (remote) B2B contract About the role In this role, you will improve the security and resilience of a large-scale healthcare product used in enterprise environments. Working within an extended security engineering team, you will help identify, analyze, and remediate vulnerabilities across a mature C++ application while collaborating closely with architects, QA engineers, security specialists, and experienced product developers. Your work will directly contribute to reducing technical risk and strengthening secure software development practices. Responsibilities Analyze assigned security requirements and security findings Implement security-related changes in the healthcare product Remediate vulnerabilities such as unsafe input and length handling, buffer-overflow or memory-corruption risks, and SQL injection Work safely with a large legacy C++ codebase, including pointer-based and memory-sensitive logic Maintain and improve existing threading components Identify technical impact and regression risks before modifying existing functionality Participate in code reviews, testing, debugging, and troubleshooting Continuously integrate changes into the existing product and collaborate closely with the client's developers and architects Requirements Strong commercial experience with C++, including mature or legacy C++ codebases Advanced knowledge of low-level programming, including pointers, pointer arithmetic, manual memory management, bounds checking, and memory safety Proven experience identifying and remediating native-code vulnerabilities such as buffer overflows, memory corruption issues, and unsafe input handling Practical experience working with multithreaded applications and thread-safe development approaches Strong understanding of object-oriented programming principles and software design concepts Familiarity with Qt or other desktop UI frameworks is an advantage Experience developing Windows or Windows Server-based enterprise applications is an advantage Good knowledge of SQL and secure database interaction principles; Oracle Database experience is a plus Exposure to ISAM or other legacy data-storage technologies is beneficial Well-developed debugging, troubleshooting, and analytical problem-solving skills Experience with secure software development and remediation of documented security findings is strongly preferred Proficiency in close collaboration with architects, QA engineers, security experts, and existing product developers