Making Open Work
May 8–9, 2017: Training & Tutorials
May 10–11, 2017: Conference
Austin, TX

Slow-mo code

11:50am12:30pm Wednesday, May 10, 2017
Location: Meeting Room 9 A/B
Level: Intermediate
Average rating: ***..
(3.33, 3 ratings)

Who is this presentation for?

  • Experienced devs looking to make the leap to writing optimized interpreted code

Prerequisite knowledge

  • A core understanding of Ruby syntax and basic data structures (e.g., hashes)

What you'll learn

  • Gain experience with stackprof and the concept of stack sampling profilers
  • Understand how to use high-level language features to achieve large speed increases without sacrificing readability or maintainability
  • Learn a general process for improving the performance of a known piece of slow code


No one wants to be stuck in the slow lane, especially Rubyists, but many Rubyists aren’t familiar or comfortable with many benchmarking tools, so their code is slow. Drawing on technical work done on Sprockets internals, Richard Schneeman discusses the slow process of writing fast code, exploring several real-world performance optimizations using use stackprof and other low level profiling tools as well as benchmark-ips and simple bash scripts that look strange but make your code faster by fixing performance problems. Richard then rewinds to show how these slow spots were found and fixed. Join Richard to “C” how fast your Ruby can “Go.”

Photo of Richard Schneeman

Richard Schneeman


Richard “Schneems” Schneeman is a programmer at Heroku. A mechanical engineer turned to the dark side of programming, Schneems focuses on performance and open source. He is one of the top 50 contributors to Ruby on Rails and is the current maintainer of Sprockets. He’s know for writing Ruby libraries such as Wicked and Derailed Benchmarks. He also runs a service to get people started with their open source journey. You can read his writing at