Thierry Joyal
Senior Staff Software Engineer at Shopify
Montreal, Quebec, Canada
Summary
🤩
Rockstar🎓
Top SchoolThierry Joyal is a Senior Staff Software Engineer in Montreal with 14 years of experience building resilient backend systems and operational tooling, currently leading engineering efforts at Shopify. He favors outcome-driven delivery—shipping fast, iterating, and improving stability—and has progressed through roles from software engineer to production engineering lead and staff engineer within Shopify. Thierry is an active open-source contributor in prominent Ruby projects (including Shopify’s own shopify_app, the Liquid templating engine, and IdentityCache), where his work improved initialization safety, caching correctness, error handling, and test coverage. His background spans DevOps, automation, and backend development—bringing practical experience with Puppet, Jenkins, AWS, and large-scale Rails systems. Notably, he blends deep ActiveRecord/caching knowledge with production-facing reliability work, making him effective at fixing subtle correctness and invalidation issues that surface at scale. He holds a computer science degree from Université du Québec à Montréal and a track record of turning complex production constraints into robust, maintainable solutions.
14 years of coding experience
11 years of employment as a software developer
DEC, Informatique de gestion, DEC, Informatique de gestion at Collège Lionel-GroulxBaccalauréat en informatique et génie logiciel, Informatique, Baccalauréat en informatique et génie logiciel, Informatique at Université du Québec à Montréal
French, English
Github Skills (19)
ruby-rails10
caching10
test-driven-design10
shopify10
rails10
ruby10
activerecord10
test-automation10
api-design9
testing9
apidoc9
object-oriented-programming9
api9
disk-cache9
web-cache9
Programming languages (9)
Github contributions (5)
Shopify/liquid
Apr 2014 - Mar 2022
Liquid markup language. Safe, customer facing template language for flexible web apps.
Role in this project:
Back-end Developer
Back-end DeveloperContributions:16 reviews, 46 commits, 32 PRs in 7 years 11 months
Contributions summary:Thierry primarily contributed to the core logic of the Liquid templating engine. Their work includes refactoring and enhancing error handling, and updating the `Drop` class. They also implemented new features related to method missing behavior in Liquid drops and added CGI powered filters. Additionally, the user improved test coverage for the templating engine.
hamltemplatemarkup-languageliquidweb-apps
Shopify/identity_cache
Jan 2014 - Nov 2016
IdentityCache is a blob level caching solution to plug into Active Record. Don't #find, #fetch!
Role in this project:Back-end Developer
Back-end DeveloperContributions:13 commits, 1 PR, 1 push in 2 years 10 months
Contributions summary:Thierry primarily focused on optimizing and maintaining the `IdentityCache` library, a caching solution for ActiveRecord. Their contributions included optimizing the handling of nil IDs, improving cache invalidation logic, and adding regression tests. They also addressed issues related to parent cache invalidation in the context of embedded associations. The commits suggest expertise in ActiveRecord and caching strategies.
webscalerailsblobcachinghotel-booking
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