Shopify CLI Warnings - MacOS Homebrew - "Warning: Add xxxx to your Gemfile or gemspec"

Topic summary

Users are encountering Ruby gem warnings when running shopify theme dev after installing Shopify CLI 3.53.0+ via Homebrew on macOS. The warnings indicate that three gems (observer, base64, and webrick) will no longer be part of Ruby’s default gems starting with Ruby 3.4.0 and should be added to Gemfile or gemspec.

Current Status: Multiple users confirm experiencing the identical issue with recent CLI versions (3.53.0-3.54.0).

Workaround Available:
One user suggests manually editing the Gemfile located at:
/opt/homebrew/Cellar/shopify-cli/3.54.0/libexec/lib/node_modules/@shopify/theme/node_modules/@shopify/cli-kit/assets/cli-ruby/Gemfile

Add these three lines below line 7:

  • gem “observer”
  • gem “webrick”
  • gem “base64”

Important Note: The CLI functionality continues to work despite the warnings. One participant reported the issue resolved after updating to the newest Homebrew CLI version, though the discussion remains open regarding whether this is a permanent fix or requires the manual workaround.

Summarized with AI on November 11. AI used: claude-sonnet-4-5-20250929.

Anyone else getting these warnings? I just did a fresh Shopify CLI install on my MacBook via Homebrew. Not sure how to remedy but these appear every time I run: shopify theme dev.

I’ve tried reinstalling CLI.

/opt/homebrew/Cellar/shopify-cli/3.53.0/libexec/lib/node_modules/@shopify/theme/node_modules/@shopify/cli-kit/assets/cli-ruby/bin/shopify:9: warning: observer was loaded from the standard library, but will no longer be part of the default gems since Ruby 3.4.0. Add observer to your Gemfile or gemspec.
/opt/homebrew/Cellar/shopify-cli/3.53.0/libexec/lib/node_modules/@shopify/theme/node_modules/@shopify/cli-kit/assets/cli-ruby/bin/shopify:9: warning: webrick was loaded from the standard library, but is not part of the default gems since Ruby 3.0.0. Add webrick to your Gemfile or gemspec.
/opt/homebrew/Cellar/shopify-cli/3.53.0/libexec/lib/node_modules/@shopify/theme/node_modules/@shopify/cli-kit/assets/cli-ruby/bin/shopify:9: warning: base64 was loaded from the standard library, but will no longer be part of the default gems since Ruby 3.4.0. Add base64 to your Gemfile or gemspec.
5 Likes

Just updated to the latest version - Got the exact same issue.

1 Like

The same issue, any ideas?

Looks like this is related to latest cli version. But it works well.
If you don’t want to see warnings there, you can modify this file /opt/homebrew/Cellar/shopify-cli/3.54.0/libexec/lib/node_modules/@shopify/theme/node_modules/@shopify/cli-kit/assets/cli-ruby/Gemfile
and add this:

gem “observer”
gem “webrick”
gem “base64”
below line 7.
but better to wait for cli update.

5 Likes

Fixed this, by updating my CLI to newest version with Homebrew