Company description Publicis Sapient is a digital transformation partner helping established organizations get to their future, digitally enabled state, both in the way they work and the way they serve their customers. We help unlock value through a start-up mindset and modern methods, fusing strategy, consulting, and customer experience with agile engineering and problem-solving creativity. United by our core values and our purpose of helping people thrive in the brave pursuit of next, our 20,000+ people in 53 offices around the world combine experience across technology, data sciences, consulting, and customer obsession to accelerate our clients’ businesses through designing the products and services their customers truly value. Responsibilities We're seeking a Senior C++ Engineer to join a team working on the refactoring and enhancement of a critical, production-grade application. This role focuses on improving and evolving an existing C++ codebase while preserving current system behavior, architecture, and technology choices. The successful candidate will be comfortable understanding complex legacy code, identifying technical debt, and implementing improvements within an established environment without introducing major technology changes. Your Impact Analyze and understand complex legacy C++ codebases to support ongoing refactoring initiatives. Refactor existing components to improve maintainability, readability, performance, and code quality. Identify and resolve defects, inefficiencies, and architectural issues while preserving existing functionality. Collaborate with architects, technical leads, and engineers to define safe and incremental refactoring strategies. Conduct code reviews and promote engineering best practices across the team. Improve unit testing coverage and support validation of refactored functionality. Document technical findings, design decisions, and refactoring approaches for future maintainability. Qualifications Skills & Experience Strong professional experience developing production applications in C++. Experience working with large, legacy, or long-lived enterprise codebases. Proven experience performing code refactoring, code modernization, or technical debt reduction initiatives. Strong understanding of object-oriented design principles, design patterns, and software engineering best practices. Experience debugging complex systems and performing root cause analysis. Solid understanding of memory management, performance optimization, and code quality practices in C++. Experience using source control systems such as Git. Strong communication skills and ability to collaborate in distributed teams. Set Yourself Apart With Experience reverse-engineering undocumented or poorly documented systems. Experience improving testability and automated test coverage in legacy applications. Familiarity with static code analysis, profiling, and performance diagnostic tools. Experience working in regulated or mission-critical environments where backward compatibility is required. Exposure to AI-assisted development tools such as GitHub Copilot, Claude Code, or similar engineering productivity tools. Experience supporting incremental modernization initiatives while maintaining existing architecture constraints. Soft Skills Strong analytical and problem-solving mindset. Ability to work effectively within established technical constraints. Attention to detail and commitment to code quality. Collaborative approach to technical discussions and decision-making. Ownership mentality with focus on delivering sustainable improvements. Additional information As part of our dedication to an inclusive and diverse workforce, Publicis Sapient is committed to Equal Employment Opportunity without regard for race, color, national origin, ethnicity, gender, protected veteran status, disability, sexual orientation, gender identity, or religion. We are also committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If you need assistance or an accommodation due to a disability, you may contact us at hiring@publicis.sapient.com