Tuesday, August 4, 2026

On Rails — Aaron Patterson: Ractors, JIT Compilers, and Rewriting How Gems Install

Posted by Rails Foundation and Robby Russell

In this episode of On Rails, Robby is joined by Aaron Patterson, better known online as Tenderlove, a senior staff engineer on Shopify’s Ruby infrastructure team and a longtime contributor to both Ruby and Rails Core. Aaron and Robby chat about how Ractors are finally bringing true multi-core parallelism to Ruby, the proposal Aaron has pitched to RubyGems.org for content addressable gems that could make bundle install dramatically faster, and the real reasons gems reach for native C extensions in the first place.

They also have a candid conversation about how Aaron actually uses AI day to day, from digging through unfamiliar code at Shopify's scale to building a JPEG encoder almost entirely with Claude, and why he still can't quite bring himself to trust it the way he trusts a longtime teammate.

Links

Tenderlove
Shopify
Ractors
RubyGems.org
FFI 

Listen to this episode (1h 23m) or subscribe to On Rails in your podcast player.