Job description agileengine is an inc. * company that creates award-winning software for fortune 500 brands and trailblazing startups across 17+ industries.we rank among the leaders in areas like application development and ai/ml, and our people-first culture has earned us 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 backend engineer, you will design and optimize high-performance, multi-threaded systems, transforming legacy workflows into scalable, thread-safe architectures.leveraging deep expertise in c#, sql, and aws, you'll drive concurrency improvements, enhance system throughput, and support large-scale data processing with technologies like apache spark.this role offers strong technical ownership and the opportunity to shape reliable, high-impact backend systems in complex environments.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; - 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 - 4+ years of experience as a software engineer; - expert-level proficiency in c# with experience in multi-threaded and parallel processing; - understanding of c++ ; - 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 ; - proven experience deploying solutions on aws ; - strong problem-solving and debugging skills focused on scalability and reliability; - upper-intermediate english level.nice to haves - hands-on experience with apache spark; - 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 cross-functional teams.perks and benefits - professional growth: mentorship, techtalks, and personalized growth roadmaps.- competitive compensation: usd-based pay with education, fitness, and team activity budgets.- exciting projects: modern solutions with fortune 500 and top product companies.- flextime: flexible schedule with remote and office options.requirements - 2–3+ years of experience in growth or marketing performance roles — ideally in the b2b saas or tech services space.- understanding of the ai market landscape, with the ability to promote ai development services and translate technical capabilities into marketing messages.- proven experience running successful marketing campaigns and managing performance metrics.- familiarity with crm and sales engagement platforms (e.g. Instantly, reply.io, apollo).- strong analytical skills with the ability to interpret data and generate actionable insights.- excellent organizational skills and attention to detail.- strong written and verbal communication skills in english.