CI Template Library

A comprehensive collection of reusable GitLab CI/CD templates that eliminated code duplication across 50+ game development repositories.

Problem

Our team was managing dozens of game projects, each with similar but slightly different CI/CD configurations. This led to:

Maintenance nightmare: Updates required changes across multiple repositories
Inconsistent builds: Different projects used different Node.js versions, linting rules, and deployment strategies
Developer friction: New projects required copying and modifying existing CI configurations

Solution

I designed and implemented a modular CI template system using GitLab's include functionality:

Template Structure

# templates/base.yml
.base_job:
  image: node:18-alpine
  before_script:
    - npm ci --cache .npm --prefer-offline
  cache:
    key: ${CI_COMMIT_REF_SLUG}
    paths:
      - .npm/

# templates/test.yml
include:
  - local: '/templates/base.yml'

test:
  extends: .base_job
  stage: test
  script:
    - npm run test:coverage
  coverage: '/Lines\s*:\s*(\d+\.\d+)%/'

Project Integration

Projects can now include only the templates they need:

# Project's .gitlab-ci.yml
include:
  - project: 'platform/ci-templates'
    ref: v2.1.0
    file:
      - '/templates/test.yml'
      - '/templates/build.yml'
      - '/templates/deploy.yml'

stages:
  - test
  - build
  - deploy

Impact

90% reduction in CI configuration duplication
Zero-downtime updates: Template changes propagate automatically
Faster onboarding: New projects get CI in 5 minutes vs 2 hours
Standardized quality: All projects use the same linting, testing, and security scanning

Technical Details

The system uses GitLab's remote include feature with semantic versioning. Each template is thoroughly tested in a dedicated test project before release.

Key Features

Semantic versioning for backward compatibility
Parameterized templates for customization
Comprehensive documentation with examples
Automated testing of template changes

This project demonstrates how thoughtful abstraction can dramatically improve developer experience while maintaining flexibility.