Contributor and Development Docs

Learn the processes and technical information needed for contributing to GitLab.

This content is intended for members of the GitLab Team as well as community contributors. Content specific to the GitLab Team should instead be included in the Handbook.

For information on using GitLab to work on your own software projects, see the GitLab user documentation.

For information on working with the GitLab APIs, see the API documentation.

For information about how to install, configure, update, and upgrade your own GitLab instance, see the administration documentation.

Get started

• Set up the GitLab development environment with the GitLab Development Kit (GDK)
• GitLab contributing guide
  • Issues workflow for more information about:
    • Issue tracker guidelines.
    • Triaging.
    • Labels.
    • Feature proposals.
    • Issue weight.
    • Regression issues.
    • Technical or UX debt.
  • Merge requests workflow for more information about:
    • Merge request guidelines.
    • Contribution acceptance criteria.
    • Definition of done.
    • Dependencies.
  • Style guides
  • Implement design & UI elements
• GitLab Architecture Overview
• Rake tasks for development

Processes

Must-reads:

• Guide on adapting existing and introducing new components
• Code review guidelines for reviewing code and having code reviewed
• Database review guidelines for reviewing database-related changes and complex SQL queries, and having them reviewed
• Secure coding guidelines
• Pipelines for the GitLab project

Complementary reads:

• GitLab core team & GitLab Inc. contribution process
• Security process for developers
• Guidelines for implementing Enterprise Edition features
• Danger bot
• Generate a changelog entry with bin/changelog
• Requesting access to ChatOps on GitLab.com (for GitLab team members)
• Patch release process for developers
• Adding a new service component to GitLab

Development guidelines review

When you submit a change to the GitLab development guidelines, who you ask for reviews depends on the level of change.

Wording, style, or link changes

Not all changes require extensive review. For example, MRs that don't change the content's meaning or function can be reviewed, approved, and merged by any maintainer or Technical Writer. These can include:

• Typo fixes.
• Clarifying links, such as to external programming language documentation.
• Changes to comply with the Documentation Style Guide that don't change the intent of the documentation page.

Specific changes

If the MR proposes changes that are limited to a particular stage, group, or team, request a review and approval from an experienced GitLab Team Member in that group. For example, if you're documenting a new internal API used exclusively by a given group, request an engineering review from one of the group's members.

After the engineering review is complete, assign the MR to the Technical Writer associated with the stage and group in the modified documentation page's metadata.

If you have questions or need further input, request a review from the Technical Writer assigned to the Development Guidelines.

Broader changes

Some changes affect more than one group. For example:

• Changes to code review guidelines.
• Changes to commit message guidelines.
• Changes to guidelines in feature flags in development of GitLab.
• Changes to feature flags documentation guidelines.

In these cases, use the following workflow:

1. Request a peer review from a member of your team.

2. Request a review and approval of an Engineering Manager (EM) or Staff Engineer who's responsible for the area in question:

   • Frontend
   • Backend
   • Database
   • User Experience (UX)
   • Security
   • Quality
     • Engineering Productivity
   • Infrastructure
   • Technical Writing

   You can skip this step for MRs authored by EMs or Staff Engineers responsible for their area.

   If there are several affected groups, you may need approvals at the EM/Staff Engineer level from each affected area.

3. After completing the reviews, consult with the EM/Staff Engineer author / approver of the MR.

   If this is a significant change across multiple areas, request final review and approval from the VP of Development, the DRI for Development Guidelines, @clefelhocz1.

4. After all approvals are complete, assign the merge request to the Technical Writer for Development Guidelines for final content review and merge. The Technical Writer may ask for additional approvals as previously suggested before merging the MR.

UX and Frontend guides

• GitLab Design System, for building GitLab with existing CSS styles and elements
• Frontend guidelines
• Emoji guide

Backend guides

• Directory structure
• GitLab utilities
• Issuable-like Rails models
• Logging
• API style guide for contributing to the API
• GraphQL API style guide for contributing to the GraphQL API
• Sidekiq guidelines for working with Sidekiq workers
• Working with Gitaly
• Manage feature flags
• Licensed feature availability
• Dealing with email/mailers
• Shell commands in the GitLab codebase
• Gemfile guidelines
• Pry debugging
• Sidekiq debugging
• Accessing session data
• Gotchas to avoid
• Avoid modules with instance variables, if possible
• How to dump production data to staging
• Working with the GitHub importer
• Import/Export development documentation
• Test Import Project
• Elasticsearch integration docs
• Working with Merge Request diffs
• Kubernetes integration guidelines
• Permissions
• Guidelines for reusing abstractions
• DeclarativePolicy framework
• How Git object deduplication works in GitLab
• Geo development
• Routing
• Repository mirroring
• Git LFS
• Developing against interacting components or features
• File uploads
• Auto DevOps development guide
• Mass Inserting Models
• Value Stream Analytics development guide
• Issue types vs first-class types
• Application limits
• Redis guidelines
• Rails initializers
• Code comments
• Renaming features
• Windows Development on GCP
• Code Intelligence
• Approval Rules
• Feature categorization
• Wikis development guide
• Newlines style guide
• Image scaling guide
• Export to CSV

Performance guides

• Instrumentation for Ruby code running in production environments.
• Performance guidelines for writing code, benchmarks, and certain patterns to avoid.
• Merge request performance guidelines for ensuring merge requests do not negatively impact GitLab performance
• Profiling a URL, measuring performance using Sherlock, or tracking down N+1 queries using Bullet.
• Cached queries guidelines, for tracking down N+1 queries masked by query caching, memory profiling and why should we avoid cached queries.

Database guides

See database guidelines.

Integration guides

• Jira Connect app
• Security Scanners
• Secure Partner Integration
• How to run Jenkins in development environment
• How to run local Codesandbox integration for Web IDE Live Preview

Testing guides

• Testing standards and style guidelines
• Frontend testing standards and style guidelines

Refactoring guides

• Refactoring guidelines

Deprecation guides

• Deprecation guidelines

Documentation guides

• Writing documentation
• Documentation style guide
• Markdown

Internationalization (i18n) guides

• Introduction
• Externalization
• Translation

Product Intelligence guides

• Product Intelligence guide
• Usage Ping guide
• Snowplow guide

Experiment guide

• Introduction

Build guides

• Building a package for testing purposes

Compliance

• Licensing for ensuring license compliance

Go guides

• Go Guidelines

Shell Scripting guides

• Shell scripting standards and style guidelines

Domain-specific guides

• CI/CD development documentation

Other Development guides

• Defining relations between files using projections
• Reference processing
• Compatibility with multiple versions of the application running at the same time
• Features inside .gitlab/
• Dashboards for stage groups
• Preventing transient bugs

Other GitLab Development Kit (GDK) guides

• Run full Auto DevOps cycle in a GDK instance
• Using GitLab Runner with the GDK
• Using the Web IDE terminal with the GDK