API Automate GitLab via a simple and powerful API.
GitLab as OAuth2 authentication service provider. It allows you to login to other applications from GitLab.
GitLab Basics Find step by step how to start working on your commandline and on GitLab.
Importing to GitLab.
Markdown GitLab's advanced formatting system.
Permissions Learn what each role in a project (guest/reporter/developer/master/owner) can do.
Profile Settings
Project Services Integrate a project with external services, such as CI and chat.
Public access Learn how you can allow public and internal access to projects.
SSH Setup your ssh keys and deploy keys for secure access to your projects.
Web hooks Let GitLab notify you when new code has been pushed to your project.
Workflow Using GitLab functionality and importing projects from GitHub and SVN.

CI Documentation

Test and deploy Ruby applications to Heroku
Test and deploy Python applications to Heroku
Test Clojure applications
Help your favorite programming language and GitLab by sending a merge request with a guide for that language.

Administrator documentation

Audit Events Check how user access changed in projects and groups.
Changing the appearance of the login page Make the login page branded for your GitLab instance.
Custom git hooks Custom git hooks (on the filesystem) for when web hooks aren't enough.
Email Email GitLab users from GitLab
Git Hooks Advanced push rules for your project.
Help message Set information about administrators of your GitLab instance.
Install Requirements, directory structures and installation from source.
Integration How to integrate with systems such as JIRA, Redmine, LDAP and Twitter.
Issue closing Customize how to close an issue from commit messages.
Libravatar Use Libravatar for user avatars.
Log system Log system.
Operations Keeping GitLab up and running
Raketasks Backups, maintenance, automatic web hook setup and the importing of projects.
Security Learn what you can do to further secure your GitLab instance.
System hooks Notifications when users, projects and keys are changed.
Update Update guides to upgrade your installation.
Welcome message Add a custom welcome message to the sign-in page.
Reply by email Allow users to comment on issues and merge requests by replying to notification emails.
Migrate GitLab CI to CE/EE Follow this guide to migrate your existing GitLab CI data to GitLab CE/EE.
Downgrade back to CE Follow this guide if you need to downgrade from EE to CE.
Git LFS configuration