diff --git a/.github/workflows/release-rubygem.yaml b/.github/workflows/release-rubygem.yaml
index 301a923a..d6932f1a 100644
--- a/.github/workflows/release-rubygem.yaml
+++ b/.github/workflows/release-rubygem.yaml
@@ -23,6 +23,10 @@ jobs:
         with:
           ruby-version: 4.0.6
           working-directory: ruby
+      - name: Synchronize CiEnvironments.json
+        working-directory: ruby
+        run: bundle exec rake ci_environments
+      - run: ./scripts/fail-if-dirty
       - uses: rubygems/configure-rubygems-credentials@dc5a8d8553e6ee01fc26761a49e99e733d17954a # v2.1.0
       - uses: cucumber/action-publish-rubygem@4e79bb9aed597c835e8438f57c04d0996ab80d72 # v2.0.0
         with:
diff --git a/.github/workflows/test-ruby.yaml b/.github/workflows/test-ruby.yaml
index 46710276..610cc707 100644
--- a/.github/workflows/test-ruby.yaml
+++ b/.github/workflows/test-ruby.yaml
@@ -28,12 +28,12 @@ jobs:
       fail-fast: true
       matrix:
         os: [ubuntu-latest]
-        ruby: ['3.2', '3.3', '3.4', '3.5']
+        ruby: ['3.2', '3.3', '3.4', '4.0']
         include:
           - os: windows-latest
-            ruby: '3.4'
+            ruby: '4.0'
           - os: macos-latest
-            ruby: '3.4'
+            ruby: '4.0'
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 723d4b76..103c2741 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
+### Fixed
+- [Ruby] Ensure `CiEnvironments.json` is published (in new dir), in gem package
+- BREAKING CHANGE: [Ruby] change `VariableExpression` module namespace to be top level alongside `CiEnvironment` module
 
 ## [14.0.0] - 2026-06-11
 ### Changed
diff --git a/ruby/.gitignore b/ruby/.gitignore
index 5e7eec9f..463c834f 100644
--- a/ruby/.gitignore
+++ b/ruby/.gitignore
@@ -3,7 +3,6 @@ coverage/
 pkg/
 *.gem
 .compared
-.deps
-.tested*
+lib/cucumber/CiEnvironments.json
 *-go
 *.iml
diff --git a/ruby/.rubocop_todo.yml b/ruby/.rubocop_todo.yml
index bdf91a04..1fa9bf2e 100644
--- a/ruby/.rubocop_todo.yml
+++ b/ruby/.rubocop_todo.yml
@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2025-10-07 17:03:37 UTC using RuboCop version 1.81.1.
+# on 2026-07-22 07:32:12 UTC using RuboCop version 1.81.1.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
@@ -9,19 +9,14 @@
 # TODO: Oct '23 -> 10 files inspected, 63 offenses detected, 53 offenses autocorrectable
 # TODO: Nov '24 -> 9 files inspected, 4 offenses detected, 0 offenses autocorrectable
 # TODO: Oct '25 -> 9 files inspected, 5 offenses detected, 1 offenses autocorrectable
+# TODO: Jul '26 -> 7 files inspected, 2 offenses detected
 
 # Offense count: 1
-# This cop supports safe autocorrection (--autocorrect).
-Layout/EmptyLinesAfterModuleInclusion:
-  Exclude:
-    - 'lib/cucumber/ci_environment.rb'
-
-# Offense count: 2
 # Configuration parameters: AllowedMethods, AllowedPatterns, CountRepeatedAttributes.
 Metrics/AbcSize:
   Max: 22
 
-# Offense count: 2
+# Offense count: 1
 # Configuration parameters: CountComments, CountAsOne, AllowedMethods, AllowedPatterns.
 Metrics/MethodLength:
-  Max: 23
+  Max: 21
diff --git a/ruby/Rakefile b/ruby/Rakefile
index e00ae19c..6341b384 100644
--- a/ruby/Rakefile
+++ b/ruby/Rakefile
@@ -3,7 +3,7 @@
 $LOAD_PATH.unshift(File.expand_path('lib', __dir__))
 
 file :ci_environments do
-  FileUtils.cp('../CiEnvironments.json', 'lib/cucumber/ci_environment/CiEnvironments.json')
+  FileUtils.cp('../CiEnvironments.json', 'lib/cucumber/CiEnvironments.json')
 end
 
 desc 'Copy the sample environments & run all the unit tests for all environment types'
diff --git a/ruby/cucumber-ci-environment.gemspec b/ruby/cucumber-ci-environment.gemspec
index 91bb3985..333aa3cb 100644
--- a/ruby/cucumber-ci-environment.gemspec
+++ b/ruby/cucumber-ci-environment.gemspec
@@ -5,7 +5,7 @@ version = File.read(File.expand_path('VERSION', __dir__)).strip
 Gem::Specification.new do |s|
   s.name        = 'cucumber-ci-environment'
   s.version     = version
-  s.authors     = ['Vincent Prêtre']
+  s.authors     = ['Vincent Prêtre', 'Luke Hill']
   s.description = 'Detect CI Environment from environment variables'
   s.summary     = "#{s.name}-#{s.version}"
   s.email       = 'cukes@googlegroups.com'
diff --git a/ruby/lib/cucumber/ci_environment.rb b/ruby/lib/cucumber/ci_environment.rb
index 8a768859..f713bb59 100644
--- a/ruby/lib/cucumber/ci_environment.rb
+++ b/ruby/lib/cucumber/ci_environment.rb
@@ -2,79 +2,78 @@
 
 require 'uri'
 require 'json'
-require 'cucumber/ci_environment/variable_expression'
+require 'cucumber/variable_expression'
 
 module Cucumber
-  module CiEnvironment
+  class CiEnvironment
     extend VariableExpression
-    CI_ENVIRONMENTS_PATH = File.join(File.dirname(__FILE__), 'ci_environment/CiEnvironments.json')
 
-    module_function
+    CI_ENVIRONMENTS_PATH = File.join(File.dirname(__FILE__), './CiEnvironments.json')
 
-    def detect_ci_environment(env)
-      ci_environments = JSON.parse(File.read(CI_ENVIRONMENTS_PATH))
-      ci_environments.each do |ci_environment|
-        detected = detect(ci_environment, env)
-        return detected unless detected.nil?
-      end
-
-      nil
-    end
+    class << self
+      def detect_ci_environment(env)
+        ci_environments = JSON.parse(File.read(CI_ENVIRONMENTS_PATH))
+        ci_environments.each do |ci_environment|
+          detected = detect(ci_environment, env)
+          return detected unless detected.nil?
+        end
 
-    def detect(ci_environment, env)
-      url = evaluate(ci_environment['url'], env)
-      return nil if url.nil?
+        nil
+      end
 
-      result = {
-        name: ci_environment['name'],
-        url: url,
-        buildNumber: evaluate(ci_environment['buildNumber'], env)
-      }
+      def remove_userinfo_from_url(value)
+        return nil if value.nil?
 
-      detected_git = detect_git(ci_environment, env)
-      result[:git] = detected_git if detected_git
-      result
-    end
+        begin
+          uri = URI(value)
+          uri.userinfo = ''
+          uri.to_s
+        rescue StandardError
+          value
+        end
+      end
 
-    def detect_git(ci_environment, env)
-      revision = detect_revision(ci_environment, env)
-      return nil if revision.nil?
+      private
 
-      remote = evaluate(ci_environment['git']['remote'], env)
-      return nil if remote.nil?
+      def detect(ci_environment, env)
+        url = evaluate(ci_environment['url'], env)
+        return nil if url.nil?
 
-      git_info = {
-        remote: remove_userinfo_from_url(remote),
-        revision: revision
-      }
+        result = {
+          name: ci_environment['name'],
+          url: url,
+          buildNumber: evaluate(ci_environment['buildNumber'], env)
+        }
 
-      tag = evaluate(ci_environment['git']['tag'], env)
-      branch = evaluate(ci_environment['git']['branch'], env)
-      git_info[:tag] = tag if tag
-      git_info[:branch] = branch if branch
-      git_info
-    end
+        detected_git = detect_git(ci_environment, env)
+        result[:git] = detected_git if detected_git
+        result
+      end
 
-    def detect_revision(ci_environment, env)
-      return evaluate(ci_environment['git']['revision'], env) unless env['GITHUB_EVENT_NAME'] == 'pull_request'
+      def detect_git(ci_environment, env)
+        revision = detect_revision(ci_environment, env)
+        return nil if revision.nil?
 
-      raise StandardError('GITHUB_EVENT_PATH not set') unless env['GITHUB_EVENT_PATH']
+        remote = evaluate(ci_environment['git']['remote'], env)
+        return nil if remote.nil?
 
-      event = JSON.parse(File.read(env['GITHUB_EVENT_PATH']))
-      event.dig('pull_request', 'head', 'sha').tap do |revision|
-        raise StandardError("Could not find .pull_request.head.sha in GITHUB_EVENT_PATH:\n#{JSON.pretty_generate(event)}") if revision.nil?
+        {
+          remote: remove_userinfo_from_url(remote),
+          revision: revision,
+          tag: evaluate(ci_environment['git']['tag'], env),
+          branch: evaluate(ci_environment['git']['branch'], env)
+        }.compact
       end
-    end
 
-    def remove_userinfo_from_url(value)
-      return nil if value.nil?
+      def detect_revision(ci_environment, env)
+        return evaluate(ci_environment['git']['revision'], env) unless env['GITHUB_EVENT_NAME'] == 'pull_request'
+
+        raise StandardError('GITHUB_EVENT_PATH not set') unless env['GITHUB_EVENT_PATH']
 
-      begin
-        uri = URI(value)
-        uri.userinfo = ''
-        uri.to_s
-      rescue StandardError
-        value
+        event = JSON.parse(File.read(env['GITHUB_EVENT_PATH']))
+        event.dig('pull_request', 'head', 'sha').tap do |revision|
+          raise StandardError("Could not find .pull_request.head.sha in GITHUB_EVENT_PATH:\n#{JSON.pretty_generate(event)}") if revision.nil?
+        end
       end
     end
   end
diff --git a/ruby/lib/cucumber/ci_environment/.gitignore b/ruby/lib/cucumber/ci_environment/.gitignore
deleted file mode 100644
index ab44ddb1..00000000
--- a/ruby/lib/cucumber/ci_environment/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-CiEnvironments.json
diff --git a/ruby/lib/cucumber/ci_environment/variable_expression.rb b/ruby/lib/cucumber/ci_environment/variable_expression.rb
deleted file mode 100644
index dadf80a2..00000000
--- a/ruby/lib/cucumber/ci_environment/variable_expression.rb
+++ /dev/null
@@ -1,49 +0,0 @@
-# frozen_string_literal: true
-
-module Cucumber
-  module CiEnvironment
-    module VariableExpression
-      def evaluate(expression, env)
-        return nil if expression.nil?
-
-        begin
-          expression.gsub(/\${(.*?)(?:(?<!\\)\/(.*)\/(.*))?}/) do
-            variable = Regexp.last_match(1)
-            pattern = Regexp.last_match(2)
-            replacement = Regexp.last_match(3)
-
-            value = get_value(variable, env)
-            raise "Undefined variable #{variable}" if value.nil?
-
-            if pattern.nil?
-              value
-            else
-              regexp = Regexp.new(pattern.gsub('\/', '/'))
-              match = value.match(regexp)
-              raise "No match for variable #{variable}" if match.nil?
-
-              match[1..].each_with_index do |group, i|
-                replacement = replacement.gsub("\\#{i + 1}", group)
-              end
-              replacement
-            end
-          end
-        rescue StandardError
-          nil
-        end
-      end
-
-      def get_value(variable, env)
-        if variable.index('*')
-          regexp = Regexp.new(variable.gsub('*', '.*'))
-          # GoCD env var with dynamic "material" name
-          # https://github.com/ashwanthkumar/gocd-build-github-pull-requests#github
-          env.each do |name, value|
-            return value if regexp.match?(name)
-          end
-        end
-        env[variable]
-      end
-    end
-  end
-end
diff --git a/ruby/lib/cucumber/variable_expression.rb b/ruby/lib/cucumber/variable_expression.rb
new file mode 100644
index 00000000..2d334adb
--- /dev/null
+++ b/ruby/lib/cucumber/variable_expression.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Cucumber
+  module VariableExpression
+    def evaluate(expression, env)
+      return nil if expression.nil?
+
+      expression.gsub(/\${(.*?)(?:(?<!\\)\/(.*)\/(.*))?}/) do
+        variable = Regexp.last_match(1)
+        pattern = Regexp.last_match(2)
+        replacement = Regexp.last_match(3)
+
+        value = get_value(variable, env)
+        raise "Undefined variable #{variable}" if value.nil?
+
+        if pattern.nil?
+          value
+        else
+          regexp = Regexp.new(pattern.gsub('\/', '/'))
+          match = value.match(regexp)
+          raise "No match for variable #{variable}" if match.nil?
+
+          match[1..].each_with_index do |group, i|
+            replacement = replacement.gsub("\\#{i + 1}", group)
+          end
+          replacement
+        end
+      end
+    rescue StandardError
+      nil
+    end
+
+    def get_value(variable, env)
+      if variable.index('*')
+        regexp = Regexp.new(variable.gsub('*', '.*'))
+        # GoCD env var with dynamic "material" name
+        # https://github.com/ashwanthkumar/gocd-build-github-pull-requests#github
+        env.each do |name, value|
+          return value if regexp.match?(name)
+        end
+      end
+      env[variable]
+    end
+  end
+end
diff --git a/ruby/spec/cucumber/ci_environment/variable_expression_spec.rb b/ruby/spec/cucumber/variable_expression_spec.rb
similarity index 93%
rename from ruby/spec/cucumber/ci_environment/variable_expression_spec.rb
rename to ruby/spec/cucumber/variable_expression_spec.rb
index f69d41ad..06faefc5 100644
--- a/ruby/spec/cucumber/ci_environment/variable_expression_spec.rb
+++ b/ruby/spec/cucumber/variable_expression_spec.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
-require 'cucumber/ci_environment'
+require 'cucumber/variable_expression'
 
-describe Cucumber::CiEnvironment::VariableExpression do
+describe Cucumber::VariableExpression do
   describe '.evaluate' do
     subject(:ci_environment) { Cucumber::CiEnvironment }