Over the past couple of weeks, there’s been some conversation about Bundler and RubyGems and their place in the Ruby community.

Shopify, pulling strings at Ruby Central, forces Bundler and RubyGems takeover
Ruby Central recently took over a collection of open source projects from their maintainers without their consent.
Bundler belongs to the Ruby community
I’ve spent 15 years of my life working on Bundler. When I introduce myself, people say “oh, the Bundler guy?”, and I am forced to agree. I didn’t come up with the original idea for Bundler (that was Yehuda). I also didn’t work on the first six months worth of prototypes. That was all Carl and Yehuda together, back when “Carlhuda” was a super-prolific author of Ruby libraries, including most of the work to modularize Rails for version 3.
André.Arko.netAndré Arko

Taking a step back from the drama, I’m reminded of just how much Bundler has shaped not only Ruby development, but the entire world of modern programming.

Life Before Bundler

For anyone who wasn’t around pre-2010, it’s hard to overstate how chaotic dependency management was. With RubyGems alone, you could specify gem versions, but everything was installed globally. Version conflicts were constant, reproducibility was unreliable, and the phrase “works on my machine” was far too common. Every developer was one gem install away from breaking their local environment or their production servers.

The Bundler Revolution

Bundler changed that almost overnight. It introduced a simple, elegant model:

  • A Gemfile to declare what your project needs.
  • A Gemfile.lock to lock the exact dependency graph.
  • A project-specific environment, so apps stopped trampling over each other’s gems.

This finally made deterministic builds possible. CI pipelines were now reliable. It gave teams confidence that the code they shipped would work the same way in production as it did locally.

It sounds obvious now, but it wasn’t at the time. Bundler unified ideas that had existed in various forms and made them the default. Once developers experienced that workflow, they never wanted to go back.

A Ripple Felt Everywhere

Bundler’s lockfile idea quickly spread far beyond Ruby:

  • Bundler (Ruby, 2010) – introduced Gemfile.lock, pioneering the modern lockfile pattern.
  • npm (JavaScript, 2012/2017) – first tried npm-shrinkwrap.json (2012), then standardized on package-lock.json (2017).
  • Cargo (Rust, 2014) – Yehuda Katz, a Bundler co-author, helped design Cargo with Cargo.toml + Cargo.lock.
  • Elixir (Mix/Hex, 2014) – José Valim (ex-Rails core) brought Bundler’s ideas straight into mix.lock.
  • Go Modules (2018) – introduced go.mod + go.sum to guarantee reproducibility.
  • Python (2017–2018) – Pipenv (Pipfile + Pipfile.lock) and Poetry (pyproject.toml + poetry.lock) brought Bundler-style dependency management to Python.

Bundler didn’t just fix Ruby’s dependency hell. It defined the modern standard for reproducible builds across languages.

Gratitude

Personally, I can’t imagine building DocSpring without Bundler. Our application depends on a complex set of libraries, and managing the dependency graph by hand with individual gem install commands would be a nightmare, if not downright impossible. Bundler lets me ship with confidence. What works in CI works in production, and upgrading dependencies is... easier than it would be without Bundler. (It can only do so much.)

I’m grateful to everyone who poured their time, energy, and care into Bundler over the years: Yehuda Katz, Carl Lerche, André Arko, and the 354 individuals who contributed to Bundler and to RubyGems. Their work has reshaped the daily experience of software developers everywhere.