Senior C++ Software EngineerGlobal Data Transfer & High-Performance Systems | U.S. Tech CompanyAs BestHR (employment agency no.32744), we are partnering with a highly respected U.S. technology company that builds mission-critical software enabling secure, high-speed, and reliable transfer of digital assets. Their solutions are trusted by leading global brands across multiple industries.If you want to work on extremely high-performance systems operating at massive scale—this role is for you.Your Responsibilities Develop new features for a high-performance enterprise application (billions of files, tens of Gbps throughput) Work end-to-end: concept → PoC → implementation → production release Create automated tests (unit + functional) Support customers and internal teams in solving complex product issues Requirements Strong experience in large-scale C++ development (Windows and/or Linux) Cross-platform development (Windows/Linux); macOS is a plus Proficiency with debugging/profiling tools (Win/Linux) Solid knowledge: C++11/14/17/20 Experience with automated testing Background in high-performance systems (large object sets, heavy network load, CPU/RAM-critical operations) Knowledge of low-level OS APIs (Windows, POSIX) – networking, filesystems, security, multithreading Basic understanding of networking protocols and cryptography Very good English Nice to Have Kernel-level development (Windows/Linux) Experience with FUSE or similar FS frameworks Familiarity with AWS/Azure/GCP APIs We Offer UoP or B2B – long-term cooperation Attractive salary Multisport Medicover E-learning platforms Supportive, technical environment