Used by over 100,000 organizations and ranked first in the Gartner Magic Quadrant for DevOps Platforms, GitLab is the open-core DevSecOps platform that delivers the complete software development lifecycle — from planning and source code management through CI/CD, security scanning, and monitoring — in a single self-managed application. The built-in CI/CD engine executes pipelines defined in YAML with parallel jobs, directed acyclic graph scheduling, multi-project pipelines, and auto-scaling runners on Docker, Kubernetes, or bare metal. Merge requests provide inline code review with approval rules, code owners, merge trains for serialized merging, and five merge strategies including fast-forward and semi-linear history. The integrated container registry stores Docker images alongside code, while the package registry supports npm, Maven, NuGet, PyPI, Conan, Go, and generic packages. Issue boards with epics, milestones, and labels enable agile planning, while the built-in wiki and GitLab Pages provide documentation hosting and static site publishing. Security scanning in the Community Edition includes basic SAST, secret detection, and container scanning running as pipeline jobs. The Omnibus installer bundles Rails, Puma, Gitaly, Workhorse, Nginx, PostgreSQL, Redis, Sidekiq, and Prometheus into a single package installable in minutes, while Docker and Helm chart options support containerized and Kubernetes deployments. GitLab Duo AI assists with code suggestions, merge request summaries, and vulnerability resolution. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.