Azure DevOps Custom CI Pipeline (Time Boost)

⚡ Intelligent Build Optimization for Legacy .NET Solutions

Build only what changed, not the entire solution!

Features • Problem • Solution • Setup • Documentation

🎯 Overview

This PowerShell script revolutionizes CI/CD pipelines for large .NET solutions by implementing intelligent selective building. Instead of rebuilding hundreds of projects for a single file change, it analyzes Git diff and builds only affected projects.

Perfect for:

• 🏢 Enterprise legacy applications with 100+ projects
• 🔧 Teams without Docker or modern containerization
• ⏰ Projects with 20+ minute build times
• 💰 Organizations with limited CI/CD budget

😫 The Problem

Does this sound familiar?

❌ Solution with 150+ projects
❌ Every PR triggers a full solution build
❌ 20-30 minutes waiting for a single line change
❌ Legacy codebase without Docker support
❌ No budget for proper CI/CD refactoring

Traditional MSBuild approach:

<MSBuild Projects="EntireSolution.sln" />

☝️ Rebuilds EVERYTHING, even if you changed one CSS file!

✅ The Solution

Smart Selective Building

graph LR
    A[Feature Branch] -->|Git Diff| B[Changed Files]
    B --> C[Extract Projects]
    C --> D[Build Only Changed]
    D --> E[20 min saved! ⚡]

Loading

Our approach:

<MSBuild Projects="$(projects)" />

☝️ Builds only changed projects + their dependencies!

🌟 Key Features

Feature	Description
🎯 Selective Building	Analyzes Git changes and builds only affected projects
🔍 Dependency Tracking	Automatically includes referenced projects
🌿 Branch Comparison	Compares feature branches against master/develop
🔄 PR Support	Native Azure DevOps Pull Request integration
📊 Frontend Detection	Separate tracking for frontend changes
⚙️ Customizable	Adapt to your project structure
📈 Pipeline Variables	Sets Azure DevOps variables for next steps

🛠️ Technology Stack

Technology	Purpose	Documentation
	Script Engine	Learn More
	Build System	Learn More
	CI/CD Platform	Learn More
	Version Control	Learn More

📊 Performance Comparison

Before vs After

❌ Before (Traditional Build) Full solution build ⏱️ ~25 minutes 🔨 150 projects rebuilt 💸 High Azure costs

✅ After (Selective Build) Only changed projects ⚡ ~5 minutes 🎯 3-5 projects rebuilt 💰 80% cost reduction

🎉 Result: ~20 minutes saved per build!

🚀 Quick Start

Prerequisites

# Required
- Azure DevOps account
- Git repository
- MSBuild installed
- PowerShell 5.1+

Installation

1. Clone the repository

   git clone https://github.com/damianczer/azure-devops-msbuild-auto.git

2. Add script to your pipeline

   steps:
   - task: PowerShell@2
     inputs:
       filePath: 'script.ps1'
       arguments: >
         -CompareSourceBranch "master"
         -BranchName "$(Build.SourceBranch)"
         -Repository "$(Build.SourcesDirectory)"
         -TargetBranch "$(System.PullRequest.TargetBranch)"

3. Configure MSBuild task

   - task: MSBuild@1
     condition: eq(variables['isBuildable'], 'True')
     inputs:
       solution: '$(projects)'

⚙️ Configuration Guide

Step 1: PowerShell Task Configuration

Parameters:

• CompareSourceBranch: Base branch (e.g., master, develop)
• BranchName: Current branch from pipeline variable
• Repository: Source directory path
• TargetBranch: PR target branch (for PR builds)

Step 2: Pipeline Variables

Output Variables:

• projects: Space-separated list of .csproj files
• hasFrontendChanged: Boolean flag for frontend changes
• isBuildable: Boolean flag if build is needed

Step 3: MSBuild Configuration

Build.proj Example:

<Project>
  <Target Name="BuildChanged">
    <MSBuild Projects="$(projects)" 
             Properties="Configuration=Release;Platform=Any CPU" 
             BuildInParallel="true" />
  </Target>
</Project>

🔍 How It Works

# 1️⃣ Compare branches
git diff --name-only feature-branch..master

# 2️⃣ Extract changed files
src/Feature/Authentication/code/Models/User.cs
src/Feature/Catalog/code/Services/ProductService.cs
src/Frontend/App/components/Header.tsx

# 3️⃣ Find related .csproj files
src/Feature/Authentication/Authentication.csproj
src/Feature/Catalog/Catalog.csproj

# 4️⃣ Set pipeline variables
projects = "Auth.csproj Catalog.csproj"
hasFrontendChanged = true
isBuildable = true

# 5️⃣ MSBuild uses variables
<MSBuild Projects="$(projects)" />

🎨 Customization

Adapt to Your Project Structure

The script looks for /code directory by default. Modify for your structure:

# Current structure: src/Feature/FeatureName/code/
if ($element.Contains("/code")) {
    # Extract project path
}

# Your structure: src/Modules/ModuleName/
if ($element.Contains("/Modules/")) {
    $index = $element.IndexOf("/Modules/")
    # Custom logic
}

Add Custom Patterns

# Track database changes
if ($element.Contains("/Database/")) {
    $hasDatabaseChanged = $true
}

# Track API changes
if ($element.Contains("/API/")) {
    $hasAPIChanged = $true
}

📚 Documentation

Script Parameters

Parameter	Required	Description	Example
CompareSourceBranch	✅	Branch to compare against	master, develop
BranchName	✅	Current branch name	feature/new-feature
Repository	✅	Repository path	C:\Repos\MyProject
TargetBranch	❌	PR target branch	refs/heads/develop

Output Variables

variables:
  projects: 'Project1.csproj Project2.csproj'
  hasFrontendChanged: 'true'
  isBuildable: 'true'

🤝 Contributing

Contributions are welcome! Here's how:

1. 🍴 Fork the repository
2. 🌿 Create feature branch (git checkout -b feature/AmazingFeature)
3. 💾 Commit changes (git commit -m 'Add AmazingFeature')
4. 📤 Push to branch (git push origin feature/AmazingFeature)
5. 🔀 Open Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

MIT License - Copyright (c) 2025 Damian Czerwiński

👨‍💻 Author

Damian Czerwiński

If this project helped you, please ⭐ star this repository!

💡 Questions or Issues?

Open an Issue • Discussions

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