Lead Ruby Developer Duration: 12+ Months Location: Chicago, IL Key Responsibilities & Required Technical Expertise: 12+ years of strong experience on Ruby.Deep knowledge of Ruby MRI internals (GIL, memory model, object allocation)Ruby MRI garbage collector (mark & sweep, generational GC)Strong experience with Rails internals (ActiveRecord, Arel, middleware stack)Ability to optimize slow queries, N+1 issues, and memory leaksExperience with multi-threaded / concurrent Ruby (Puma, Sidekiq tuning)Ru