GitLab Mastery: The Complete DevSecOps Platform & CI/CD Pipeline Guide

1. Single Application DevSecOps vs. Fragmented Toolchains

Modern enterprises evaluate whether to stitch together best-of-breed disparate tools or standardize on GitLab's unified architecture:

2. GitLab Runner Architecture & Executor Models

GitLab separates the coordinator (the GitLab web server) from the build execution agents (GitLab Runners). Selecting the appropriate executor determines pipeline isolation and throughput:

3. Production Blueprint: Enterprise `.gitlab-ci.yml` Pipeline

A production-ready pipeline configuration demonstrating multi-stage execution, dependency caching, automated SAST security scanning, and conditional deployment rules:

# Enterprise GitLab CI/CD Pipeline
image: node:20-alpine

stages:
  - lint
  - test
  - security
  - build
  - deploy

variables:
  npm_config_cache: "$CI_PROJECT_DIR/.npm"

cache:
  key:
    files:
      - package-lock.json
  paths:
    - .npm/

# Stage 1: Static Code Quality
lint_code:
  stage: lint
  script:
    - npm ci --prefer-offline
    - npm run lint

# Stage 2: Automated Unit Testing
unit_tests:
  stage: test
  script:
    - npm ci --prefer-offline
    - npm test -- --coverage
  artifacts:
    when: always
    reports:
      junit: junit.xml
      coverage_report:
        coverage_format: cobertura
        path: coverage/cobertura-coverage.xml

# Stage 3: Shift-Left Security Scans
include:
  - template: Security/SAST.gitlab-ci.yml
  - template: Security/Secret-Detection.gitlab-ci.yml

# Stage 4: Production Build
build_app:
  stage: build
  script:
    - npm ci --prefer-offline
    - npm run build
  artifacts:
    paths:
      - dist/
    expire_in: 1 week

# Stage 5: Deployment to Production Environment
deploy_production:
  stage: deploy
  environment:
    name: production
    url: https://app.example.com
  script:
    - echo "Deploying to production cloud cluster..."
  rules:
    - if: '$CI_COMMIT_BRANCH == "main"'
      when: manual

Frequently Asked Questions: Modern GitLab Engineering