How to Set Up a CI/CD Pipeline: Step-by-Step 2025 Guide

Let’s set up your first CI/CD pipeline from scratch. Learn GitHub Actions, automated testing, and deployment to a cloud VPS server.

What is a CI/CD Pipeline?

Every time a change is made, your code is automatically built, tested, and deployed using a CI/CD pipeline.

When developers make changes, Continuous Integration (CI) automatically builds and tests the code.
Code is automatically prepared or released to production with Continuous Delivery/Deployment (CD).

To put it simply:
Code may be moved from development to production more quickly, safely, and without the need for human labour, thanks to CI/CD.

CI vs CD vs CD — What’s the Difference?

This is confusing to a lot of people, so let’s make it simple:

• CI, or continuous integration:
  Code is often merged by developers, resulting in automatic build and test runs.
• Continuous Delivery (CD):
  Code is always prepared for deployment, but it needs to be approved manually.
• CD, or continuous deployment:
  Without human intervention, code is automatically delivered to production.

A brief synopsis

CI stands for Build & Test.
CD (Deployment) = Auto Deploy
CD (Delivery) = Ready to Deploy

Prerequisites Before You Start

Before setting up a CI/CD pipeline, make sure you have:

• Basic Git knowledge (clone, commit, push)
• Comfortable with Linux server commands
• Access to a cloud server (VPS / EC2 / Hetzner)
• A Git repository (GitHub/GitLab)

Step 1 — Choose Your CI/CD Tool

There are many CI/CD tools available. Here’s a practical comparison:

Commonly Used Tools

• Actions on GitHub
• GitLab CI/CD
• Jenkins
• CircleCI

Recommendation Matrix

Team Size	Recommended Tool
Solo / Beginner	GitHub Actions
Small Team	GitLab CI
Large Enterprise	Jenkins
SaaS Teams	CircleCI

GitHub Actions is the best option for 2025.

Since it’s

• Free for brief use
• GitHub integration
• Simple to set up

Step 2: Establish Your Branching and Repository Strategy

An effective branching strategy keeps deployment pandemonium at bay.

Suggested Organization: Main → Production dev → Development feature→New features

Workflow

• A feature branch is created by the developer
• Code is pushed ← Pull Request
• Deployment is triggered by merging into the main CI/CD pipeline after testing.

We refer to this as a streamlined Git Flow.

Step 3: Create Your Initial Pipeline File (GitHub Actions)

The crucial step is now to build your pipeline.

Create this file:

.github/workflows/deploy.yml

Example CI/CD Pipeline (Node.js App)

name: CI/CD Pipeline

on:
  push:
    branches:
      - main

jobs:
  build-test-deploy:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout code
      uses: actions/checkout@v3

    - name: Setup Node.js
      uses: actions/setup-node@v3
      with:
        node-version: '18'

    - name: Install dependencies
      run: npm install

    - name: Run tests
      run: npm test

    - name: Deploy to VPS via SSH
      uses: appleboy/[email protected]
      with:
        host: ${{ secrets.SERVER_IP }}
        username: root
        key: ${{ secrets.SSH_PRIVATE_KEY }}
        script: |
          cd /var/www/app
          git pull origin main
          npm install
          pm2 restart app

The Functions of This Pipeline

• pulls code from GitHub
• Dependencies are installed
• conducts tests
• uses SSH to deploy to your server

This pipeline consists of Build → Test → Deploy.

Step 4 — Add Automated Tests

CI/CD is dependable because of testing.

Examples of Tools

• PHP: PHPUnit
• Node.js: Jest
• Java: JUnit

The Significance of Tests

Without assessments:

• Production is affected by bugs.
• Deployments become dangerous

Fail-Fast Approach

If testing are unsuccessful, the pipeline stops right away.

Broken deployments are avoided as a result.

Step 5: Deploy on Your Server

Let’s now link your pipeline to your VPS.

Option 1: SSH Deployment (Easy & Popular)

Steps

• Generate SSH key:

ssh-keygen -t rsa

• Add public key to your server:

~/.ssh/authorized_keys

• Add secrets in GitHub:
  - SERVER_IP
  – SSH_PRIVATE_KEY

• Use SSH action (already shown above)

Option 2: Advanced Docker Deployment

Rather than directly installing code:

1. Construct a Docker image
2. Push to the registry
3. Pull and launch the server’s container

Example:

- name: Build Docker image
  run: docker build -t myapp .

- name: Run container
  run: docker run -d -p 80:80 myapp

Docker creates deployments:

• Reliable and scalable
• Easier to reverse

Common CI/CD Errors & How to Fix Them

1. Permission Denied (SSH)
   Cause: Wrong SSH key or permissions
   Fix: chmod 600 ~/.ssh/id_rsa
2. Environment Variables Not Working
   Cause: Missing secrets in pipeline
   Fix: Add them in GitHub Secrets
3. Pipeline Fails Randomly
   Cause: Dependency or caching issue
   Fix:
   – Clear cache
   – Lock dependency versions
4. Deployment Not Updating
   Cause: Git not pulling latest code
   Fix: git pull origin main

FAQ

What is the setup time for CI/CD?

For beginners: Approximately two to five hours
30 to 60 minutes for seasoned engineers

Does Docker have to be used for CI/CD?

No, because Docker creates deployments:

More dependable and easier to grow
Suggested for production settings.

Final Remarks

CI/CD is now essential for modern uses and is no longer optional.

By establishing a pipeline for CI/CD, you:

• Deploy more quickly
• Cut down on human error
• Boost dependability
• Easily scale your infrastructure