🔄 Incrementalist

Incrementalist is a .NET tool that leverages libgit2sharp and Roslyn to compute incremental build steps for large .NET solutions. It helps optimize your CI/CD pipeline by building and testing only the projects affected by your changes.

🎯 When to Use Incrementalist

Incrementalist is particularly valuable for:

🏗️ Large Solutions: If your solution contains dozens or hundreds of projects, Incrementalist can significantly reduce build times by only building what's necessary.
📦 Monorepos: When managing multiple applications or services in a single repository, Incrementalist helps identify and build only the affected components.
🌐 Microservice Architectures: In repositories containing multiple microservices, build only the services impacted by your changes.
🔗 Complex Dependencies: When projects have intricate dependencies, Incrementalist automatically determines the impacted build graph.
⚡ CI/CD Optimization: Reduce CI/CD pipeline execution time by skipping unnecessary builds and tests.

⚙️ Requirements

.NET 8.0 SDK or later
Git installed and available in the system PATH

📥 Installation

Incrementalist is available in two forms:

Incrementalist Library - a .NET 8 library for programmatic use
Incrementalist.Cmd - a dotnet tool for command-line use ( recommended)

Install the command-line tool globally:

dotnet tool install --global Incrementalist.Cmd

Or install locally in your project:

# From your repository root
dotnet new tool-manifest # if you haven't already created a .config/dotnet-tools.json
dotnet tool install Incrementalist.Cmd

Running as a Global Tool

When installed globally, run commands directly using the incrementalist command with one of the available verbs:

# Get list of affected projects
incrementalist run --dry -b dev -f ./affected-projects.txt

# List affected folders
incrementalist list-affected-folders -b dev -f ./affected-folders.txt

# Run tests for affected projects
incrementalist run -b dev -- test -c Release

# Run tests for affected projects those matching a glob
incrementalist run -b dev --target-glob "src/*.Tests.csproj" -- test -c Release

Running as a Local Tool

When using Incrementalist as a local tool, you need to use dotnet tool run with an additional -- before the Incrementalist commands:

# Get list of affected projects
dotnet incrementalist -- -b dev -f ./affected-projects.txt

# List affected folders
dotnet incrementalist -- list-affected-folders -b dev -f ./affected-folders.txt

# Build affected projects
dotnet incrementalist -- run -b dev -- build -c Release --nologo

# Run tests with coverage
dotnet incrementalist -- run -b dev -- test -c Release --no-build --logger:trx --collect:"XPlat Code Coverage" --results-directory ./testresults

# Run in parallel mode
dotnet incrementalist -- run -b dev --parallel -- build -c Release --nologo

# Save affected projects AND run commands
dotnet incrementalist -- -b dev -f ./affected-projects.txt run -- build -c Release --nologo

![NOTE] Don't call dotnet tool run incrementalist - this runs into some very annoying parse issues: https://github.com/petabridge/Incrementalist/issues/378 . Just call dotnet incrementalist instead.

📄 Configuration Files

Incrementalist supports JSON configuration files to store commonly used settings. This eliminates the need to specify the same command-line arguments repeatedly.

# Use default configuration file (.incrementalist/incrementalist.json)
incrementalist run -- build

# Specify a custom configuration file
incrementalist -c my-config.json run -- build

# Create configuration file with current settings
incrementalist create-config -b dev --verbose --parallel

Create a configuration file in your repository:

{
  "gitBranch": "dev",
  "verbose": true,
  "runInParallel": true
}

Command-line arguments take precedence over configuration file settings. See Configuration Documentation for complete details.

🚀 Quick Start Examples

# Get list of affected projects and save to file
incrementalist run --dry -b dev -f ./affected-projects.txt

# Specify solution explicitly
incrementalist run --dry -s ./src/MySolution.sln -b dev -f ./affected-projects.txt

# Get list of affected folders
incrementalist list-affected-folders -b dev -f ./affected-folders.txt

# Build only affected projects
incrementalist run -b dev -- build -c Release --nologo

# Run tests for affected projects
incrementalist run -b dev -- test -c Release --no-build --nologo

# Only include test projects in the final list
incrementalist run -b dev --target-glob "**/*.Tests.csproj" -f ./affected-test-projects.txt

# Exclude test projects from the final list
incrementalist run -b dev --skip-glob "**/*.Tests.csproj" -f ./affected-non-test-projects.txt

# Run tests with code coverage
incrementalist run -b dev -- test -c Release --no-build --nologo /p:CollectCoverage=true /p:CoverletOutputFormat=cobertura /p:CoverletOutput=./coverage/

# Save affected projects AND run commands
incrementalist run -b dev -f ./affected-projects.txt -- build -c Release --nologo

# Create configuration file with current settings (default path: .incrementalist/incrementalist.json)
incrementalist create-config -b dev --verbose --parallel

# Create configuration file with current settings and custom file name
incrementalist create-config -b dev --verbose --parallel -c ./my-incrementalist-config.json

# Run incrementalist with a custom configuration file
incrementalist run -c ./my-incrementalist-config.json -- build -c Release

# Perform a dry run without executing commands
incrementalist run -b dev --dry -- build -c Release --nologo

📄 Output Files

Incrementalist can generate two types of output files using -f, --file:

Project Lists (with the run verb):

D:\src\Project1\Project1.csproj,D:\src\Project2\Project2.csproj

Folder Lists (with the list-affected-folders verb):
```
D:\src\Project1,D:\src\Project2\SubFolder
```

These files can be used in build scripts, CI/CD pipelines, or other automation tools.

🛠️ Command-Line Options

Incrementalist now uses a verb-based command structure. Common options are available across all verbs, with some verb-specific options.

Common Options (available for all verbs)

  -s, --sln                   Optional. Solution file to analyze. Uses first .sln in
                              current directory if not specified.

  -f, --file                  Optional. Write output to the specified file.

  -b, --branch                Optional. Git branch to compare against
                              (e.g., 'dev' or 'master').

  -d, --dir                   Optional. Working directory. Defaults to current directory.

  --verbose                   Optional. (Default: false) Enable debug logging.

  -t, --timeout               Optional. (Default: 2) Solution load timeout in minutes.

  -c, --config                Optional. Path to the configuration file. Defaults to 
                              .incrementalist/incrementalist.json in the current directory.

  --continue-on-error         Optional. (Default: true) Continue executing commands even
                              if some fail.

  --parallel                  Optional. (Default: false) Execute commands in parallel.

  --parallel-limit            Optional. (Default: 0) When running in parallel, limits the
                              number of concurrent projects. 0 means no limit.

  --fail-on-no-projects       Optional. (Default: false) Fail if no projects are affected.
                        
  --skip-glob                 Optional. Glob pattern to exclude projects from the final
                              list. Applied after analyzing dependencies. Can be used
                              multiple times.

  --target-glob               Optional. Glob pattern to include only matching projects in
                              the final list. Applied after analyzing dependencies. Can
                              be used multiple times.

  --help                      Display help screen.

  --version                   Display version information.

Available Verbs

`create-config`

Creates a new configuration file with current options.

incrementalist create-config [options]

`list-affected-folders`

List affected folders instead of .NET projects.

incrementalist list-affected-folders [options]

`run`

Run a command against affected projects. Use the --dry option to test without executing.

incrementalist run [options] -- [dotnet command and arguments]

Additional options for run:

  --dry                 Optional. (Default: false) Performs a dry run without
                        executing any commands. Useful for testing.

`run-process`

Run a custom process against affected projects. Currently a discoverable alias for run that only supports dotnet commands.

incrementalist run-process [options] -- [process arguments]

Additional options for run-process:

  --process             Required. The name or path of the process to start (e.g. 'dotnet', '/bin/bash', 'mytool').
                        Currently only 'dotnet' is supported.

  --dry                 Optional. (Default: false) Performs a dry run without
                        executing any commands. Useful for testing.

⚡ Running Commands

Execute dotnet CLI commands against affected projects using the run verb:

Incrementalist

Install / Use

README