[jrhoads]

Purpose

GitHub's ubuntu-latest label is Ubuntu 26.04 as of October 2026. That image publishes Ruby 4.0.9 and does not publish Ruby 4.0.1, so ruby/setup-ruby cannot install 4.0.1 there. Master temporarily pins the Ruby CI jobs to ubuntu-24.04 so 4.0.1 still installs. This removes that pin, bumps Ruby to 4.0.9, and moves the app image to Passenger 3.2.2.

Approach

Rebased onto current master after the crass 1.0.8 bump and the ubuntu-24.04 pin landed. Keep the lockfile bump. Change the Ruby pins from 4.0.1 to 4.0.9, set the two pinned jobs back to runs-on: ubuntu-latest, and install the MySQL client library Ubuntu 26.04 actually ships.

The Passenger base image is now phusion/passenger-ruby40:3.2.2, which already defaults to Ruby 4.0.9. Ubuntu 26.04 replaced ntp with ntpsec, and replaced ntpdate with ntpsec-ntpdate.

Specs start SimpleCov before Bootsnap. On Ruby 4.0.9, InstructionSequence#to_binary raises should not compile with coverage, and Bootsnap 1.23.0's load-time probe only rescues TypeError. Bootsnap 1.26.1 handles that.

Key Modifications

• .ruby-version: ruby-4.0.1 → ruby-4.0.9
• .github/workflows/rubocop.yml and .github/workflows/parallel_ci.yml: ruby-version: 4.0.9, and runs-on: ubuntu-24.04 → ubuntu-latest
• .github/workflows/parallel_ci.yml: Sync time installs ntpsec-ntpdate and still runs ntpdate pool.ntp.org. Install libmysqlclient-dev (pulls libmysqlclient24) and key the gem cache to that library so mysql2 is not restored from a libmysqlclient.so.21 build
• Dockerfile: FROM phusion/passenger-ruby40:3.2.2, install ntpsec instead of ntp, and drop the RVM default line because the base image already provides Ruby 4.0.9
• Gemfile.lock: bootsnap 1.23.0 → 1.26.1. crass stays at 1.0.8

Important Technical Details

• A local image build of phusion/passenger-ruby40:3.2.2 completed, and the container booted. GET /heartbeat returned OK from nginx and Phusion Passenger 6.2.1, running Ruby 4.0.9.
• On Ruby 4.0.9, loading Bootsnap 1.23.0 after SimpleCov.start raises RuntimeError: should not compile with coverage from iseq.rb:23. Bootsnap 1.26.1 loads cleanly in that same setup. The Gemfile constraint ~> 1.23 already allowed 1.26.1.
• BUNDLED WITH in Gemfile.lock is Bundler 4.0.14, not a Ruby version.
• AGENTS.md still describes the Cursor Cloud VM, which has Ruby 4.0.1 installed via rbenv. That file is environment documentation, not a toolchain pin.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

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• Be humble in the language and feedback you give, ask don't tell.
• Consider using positive language as opposed to neutral when offering feedback. This is to avoid the negative bias that can occur with neutral language appearing negative.
• Offer suggestions on how to improve code e.g. simplification or expanding clarity.
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