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Ruby Project Guardrails - Gemfile Exists

Gemfile Exists

✓ Guardrail Ruby Project Guardrails Beta Devex Build And Ci
ruby.gemfile-exists

Ensures the project has a Gemfile for dependency management. Required for all Ruby projects using Bundler.

Gemfile bundler ruby project dependency management
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Compatible Integrations

This guardrail works with the following integrations. Click to see how to use Gemfile Exists with each collector.

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Gemfile Exists + Ruby Collector Provides Ruby project metadata
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Enable This Guardrail

Add the parent policy to your lunar-config.yml to enable this guardrail.

📄 lunar-config.yml 
policies:
  - uses: github://earthly/lunar-lib/policies/ruby@v1.0.5
    include: [gemfile-exists]
    # with: ...

How This Guardrail Works

This guardrail is part of the Ruby Project Guardrails policy. It evaluates data collected by integrations and produces a pass/fail check with actionable feedback.

When enabled, this check runs automatically on every PR and in AI coding workflows, providing real-time enforcement of your engineering standards.

Learn How Lunar Works →
1
↓ Integrations Gather Data
Collectors extract metadata from code, CI pipelines, tool outputs, and scans
2
{ } Centralized as JSON
All data merged into each component's unified metadata document
3
✓ This Guardrail Checks Current
Gemfile Exists runs and provides pass/fail feedback

Configuration Options

These inputs can be configured in your lunar-config.yml to customize how the parent policy (and this guardrail) behaves.

Input Required Default Description
max_audit_vulnerabilities Optional 0 Maximum allowed known vulnerabilities from bundler-audit (0 = must be clean)
min_ruby_version Optional 3.0 Minimum required Ruby version (e.g., "3.0", "3.2")
min_ruby_version_cicd Optional 3.0 Minimum required Ruby version for CI/CD commands
min_bundler_version_cicd Optional 2.4 Minimum required Bundler version for CI/CD commands
min_rake_version_cicd Optional 13.0 Minimum required Rake version for CI/CD commands

Related Guardrails

Other guardrails in the Ruby Project Guardrails policy.

Guardrail Devex Build And Ci
Lockfile Exists

Ensures the project has a Gemfile.lock for reproducible dependency resolution. Pinned dependencies prevent unexpected...
Guardrail Devex Build And Ci
Ruby Version Set

Ensures the Ruby version is explicitly specified via a .ruby-version file or a ruby directive in the Gemfile. Pinning...
Guardrail Devex Build And Ci
Bundler Audit Clean

Ensures bundler-audit reports no known vulnerabilities in the project's gem dependencies. Skips gracefully if...
Guardrail Devex Build And Ci
Min Ruby Version

Ensures the project uses at least the minimum required Ruby version. Helps maintain security and compatibility...
Guardrail Devex Build And Ci
Min Ruby Version Cicd

Ensures the Ruby version used in CI/CD commands meets the minimum required version for build environments.
Guardrail Devex Build And Ci
Min Bundler Version Cicd

Ensures the Bundler version used in CI/CD commands meets the minimum required version. Outdated Bundler versions may...
View all 8 guardrails in Ruby Project Guardrails →
Ruby Project Guardrails

Ruby Project Guardrails

This guardrail is part of the Ruby Project Guardrails policy, which includes 8 guardrails for devex build and ci.

View Policy

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