How to Fix Slow Code in Ruby - Shopify

This post details profiling and benchmarking techniques for identifying and fixing slow Ruby code. It introduces profiling tools like rbspy, stackprof, rack-mini-profiler, and app_profiler, with a case study on using App Profiler to identify unnecessary GC cycles. It also explains benchmarking using Ruby's `Benchmark` module and the `benchmark-ips` gem, demonstrating how to compare code paths and prove performance differences.