What are the responsibilities and job description for the Lead Ruby Developer position at 9AM Global LLC?
trong Expertise with Ruby:
• Minimum 12 years of 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 (Active Record, Arel, middleware
stack)
• Ability to optimize slow queries, N 1 issues, and memory leaks
• Experience with multi-threaded / concurrent Ruby (Puma, Sidekiq tuning)
• Ruby VM instruction set (YARV bytecode basics)
• Concurrent Ruby gem
• Thread pools vs Fibers vs Ractors
• Async frameworks (Falcon / Async gem)
• Experience integrating Ruby with Kafka (ruby-Kafka / Karafka), exactly-once
semantics handling
• Designing: event schemas, schema evolution (Avro / JSON schema)
Proven experience scaling Rails apps to:
• 10K RPS
• millions of daily transactions
Hands-on experience with:
• Event-driven architecture (Kafka / RabbitMQ)
• CQRS & Event Sourcing
• Saga pattern (choreography & orchestration)
Strong understanding of:
• Eventual consistency
• Distributed transactions
• Idempotent APIs
Deep understanding of:
• Caching strategies (Redis, Memcached)
• Background processing (Sidekiq, Resque)
• Database sharding and read replicas
Strong experience with:
• PostgreSQL (query tuning, indexing, vacuum, locking)
• Redis (data structures, pub/sub, distributed locks)