Senior/Lead C# Engineer (ID41548) – $2,500 Signing Bonus Join AgileEngine, an Inc. 5000 company that creates award-winning software for Fortune 500 brands and trailblazing startups across 17+ industries. It ranks among leaders in application development and AI/ML, and its people‑first culture has earned multiple Best Place to Work awards. Why Join Us If you're looking for a place to grow, make an impact, and work with people who care, we'd love to meet you! About the Role As a Senior/Lead C# Backend Engineer, you will lead the modernization of our core systems by designing and developing highly concurrent, thread‑safe applications. You’ll optimize large‑scale data operations, leverage distributed processing with Apache Spark, and deploy scalable solutions on AWS, driving performance, reliability, and scalability across our platforms. What You Will Do Lead the design and development of highly concurrent, multi‑threaded applications in C#. Re‑architect legacy synchronous workflows into scalable, thread‑safe solutions. Apply advanced knowledge of threading models, synchronization primitives, and performance tuning to optimize system throughput and minimize contention. Design, develop, and optimize complex SQL queries, stored procedures, and large‑scale data operations, including staging and transformations. Utilize Apache Spark for distributed data processing at scale. Deploy and manage solutions on AWS , ensuring reliability, scalability, and cost efficiency. Diagnose and resolve concurrency issues, perform application profiling, and drive continuous improvements in system performance. Collaborate with cross‑functional teams to define technical requirements, align architecture with business goals, and deliver high‑quality solutions. Must Haves 5+ years of expert‑level proficiency in C# with hands‑on experience in multi‑threaded and parallel processing. Strong understanding of threading models, synchronization primitives, and concurrency debugging. Proven experience in performance tuning and application profiling for large‑scale systems. Advanced proficiency in SQL (query design, optimization, and data operations). Hands‑on experience with Apache Spark for distributed data processing. Proven experience deploying solutions on AWS . Exceptional problem‑solving and debugging skills with a strong focus on scalability and reliability. Upper‑Intermediare English level. Nice to Haves Experience in re‑engineering legacy systems into modern architectures. Familiarity with microservices design principles and cloud‑native development patterns. Strong communication and collaboration skills with a track record of working in cross‑functional teams. Perks and Benefits Professional growth: Accelerate your journey with mentorship, TechTalks, and personalized growth roadmaps. Competitive compensation: We match your skills, talent, and contributions with competitive USD‑based compensation and budgets for education, fitness, and team activities. A selection of exciting projects: Work on projects with modern solutions for Fortune 500 enterprises and leading product brands. Flextime: Tailor your schedule for an optimal work‑life balance, with options to work from home or in the office. Job Details Seniority level: Mid‑Senior level Employment type: Full‑time Industries: IT Services and IT Consulting Additional Information Referrals increase your chances of interviewing at AgileEngine by 2×. #J-18808-Ljbffr