package-management

Manage NuGet packages using Central Package Management (CPM) and dotnet CLI commands. Never edit XML directly - use dotnet add/remove/list commands. Use shared version variables for related packages.

Compatible avec~Claude Code~Codex CLI~Cursor
npx add-skill https://github.com/Aaronontheweb/dotnet-skills/tree/main/skills/package-management

name: package-management description: Manage NuGet packages using Central Package Management (CPM) and dotnet CLI commands. Never edit XML directly - use dotnet add/remove/list commands. Use shared version variables for related packages. invocable: false

NuGet Package Management

When to Use This Skill

Use this skill when:

  • Adding, removing, or updating NuGet packages
  • Setting up Central Package Management (CPM) for a solution
  • Managing package versions across multiple projects
  • Troubleshooting package conflicts or restore issues

Golden Rule: Never Edit XML Directly

Always use dotnet CLI commands to manage packages. Never manually edit .csproj or Directory.Packages.props files.

# DO: Use CLI commands
dotnet add package Newtonsoft.Json
dotnet remove package Newtonsoft.Json
dotnet list package --outdated

# DON'T: Edit XML directly
# <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />

Why:

  • CLI validates package exists and resolves correct version
  • Handles transitive dependencies correctly
  • Updates lock files if present
  • Avoids typos and malformed XML
  • Works correctly with CPM

Central Package Management (CPM)

CPM centralizes all package versions in one file, eliminating version conflicts across projects.

Enable CPM

Create Directory.Packages.props in solution root:

<Project>
  <PropertyGroup>
    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
  </PropertyGroup>

  <ItemGroup>
    <PackageVersion Include="Newtonsoft.Json" Version="13.0.3" />
    <PackageVersion Include="Serilog" Version="4.0.0" />
    <PackageVersion Include="xunit" Version="2.9.2" />
  </ItemGroup>
</Project>

Project Files with CPM

Projects reference packages without versions:

<!-- src/MyApp/MyApp.csproj -->
<Project Sdk="Microsoft.NET.Sdk">
  <ItemGroup>
    <PackageReference Include="Newtonsoft.Json" />
    <PackageReference Include="Serilog" />
  </ItemGroup>
</Project>

Adding Packages with CPM

# Adds to Directory.Packages.props AND project file
dotnet add package Serilog.Sinks.Console

# Result in Directory.Packages.props:
# <PackageVersion Include="Serilog.Sinks.Console" Version="6.0.0" />

# Result in project file:
# <PackageReference Include="Serilog.Sinks.Console" />

Shared Version Variables

Group related packages with shared version variables:

<Project>
  <PropertyGroup>
    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
  </PropertyGroup>

  <!-- Shared version variables -->
  <PropertyGroup Label="SharedVersions">
    <AkkaVersion>1.5.59</AkkaVersion>
    <AkkaHostingVersion>1.5.59</AkkaHostingVersion>
    <AspireVersion>9.0.0</AspireVersion>
    <OpenTelemetryVersion>1.11.0</OpenTelemetryVersion>
    <XunitVersion>2.9.2</XunitVersion>
  </PropertyGroup>

  <!-- Akka.NET packages - all use same version -->
  <ItemGroup Label="Akka.NET">
    <PackageVersion Include="Akka" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Cluster" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Cluster.Sharding" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Cluster.Tools" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Persistence" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Streams" Version="$(AkkaVersion)" />
    <PackageVersion Include="Akka.Hosting" Version="$(AkkaHostingVersion)" />
    <PackageVersion Include="Akka.Cluster.Hosting" Version="$(AkkaHostingVersion)" />
  </ItemGroup>

  <!-- Aspire packages -->
  <ItemGroup Label="Aspire">
    <PackageVersion Include="Aspire.Hosting" Version="$(AspireVersion)" />
    <PackageVersion Include="Aspire.Hosting.AppHost" Version="$(AspireVersion)" />
    <PackageVersion Include="Aspire.Hosting.PostgreSQL" Version="$(AspireVersion)" />
    <PackageVersion Include="Aspire.Hosting.Testing" Version="$(AspireVersion)" />
  </ItemGroup>

  <!-- OpenTelemetry packages -->
  <ItemGroup Label="OpenTelemetry">
    <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="$(OpenTelemetryVersion)" />
    <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="$(OpenTelemetryVersion)" />
    <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="$(OpenTelemetryVersion)" />
    <PackageVersion Include="OpenTelemetry.Instrumentation.Http" Version="$(OpenTelemetryVersion)" />
  </ItemGroup>

  <!-- Testing -->
  <ItemGroup Label="Testing">
    <PackageVersion Include="xunit" Version="$(XunitVersion)" />
    <PackageVersion Include="xunit.runner.visualstudio" Version="$(XunitVersion)" />
    <PackageVersion Include="FluentAssertions" Version="6.12.0" />
    <PackageVersion Include="Verify.Xunit" Version="26.0.0" />
  </ItemGroup>
</Project>

Benefits:

  • Update all Akka packages by changing one variable
  • Clear organization with labeled ItemGroups
  • Prevents version mismatches in related packages

When NOT to Use CPM

Central Package Management isn't always the right choice:

Legacy Projects

Migrating an existing large solution to CPM can introduce issues:

  • Existing version conflicts become visible all at once
  • Some packages may have intentional version differences
  • Migration requires touching many files simultaneously

Recommendation: For legacy projects, migrate incrementally or stick with per-project versioning if it's working.

Version Ranges

CPM requires exact versions - it doesn't support version ranges:

<!-- NOT supported with CPM -->
<PackageVersion Include="Newtonsoft.Json" Version="[13.0,14.0)" />

<!-- Must use exact version -->
<PackageVersion Include="Newtonsoft.Json" Version="13.0.3" />

If you need version ranges (rare, but some library scenarios require it), CPM won't work.

Older .NET Versions

CPM requires:

  • .NET SDK 6.0.300+ or later
  • NuGet 6.2+ or later
  • Visual Studio 2022 17.2+ or later

If you're targeting older SDK versions or have team members on older tooling, CPM may cause build failures.

Multi-Repo Solutions

If your solution spans multiple repositories that are built independently, CPM's single Directory.Packages.props won't help - each repo needs its own.


CLI Command Reference

Adding Packages

# Add latest stable version
dotnet add package Serilog

# Add specific version
dotnet add package Serilog --version 4.0.0

# Add prerelease
dotnet add package Serilog --prerelease

# Add to specific project
dotnet add src/MyApp/MyApp.csproj package Serilog

Removing Packages

# Remove from current project
dotnet remove package Serilog

# Remove from specific project
dotnet remove src/MyApp/MyApp.csproj package Serilog

Listing Packages

# List all packages in solution
dotnet list package

# Show outdated packages
dotnet list package --outdated

# Include transitive dependencies
dotnet list package --include-transitive

# Show vulnerable packages
dotnet list package --vulnerable

# Show deprecated packages
dotnet list package --deprecated

Updating Packages

# With CPM: Edit the version in Directory.Packages.props
# Then restore to apply
dotnet restore

# Without CPM: Remove and add with new version
dotnet remove package Serilog
dotnet add package Serilog --version 4.1.0

# Or use dotnet-outdated tool (recommended)
dotnet tool install --global dotnet-outdated-tool
dotnet outdated --upgrade

Restore and Clean

# Restore packages
dotnet restore

# Clear local cache (troubleshooting)
dotnet nuget locals all --clear

# Force restore (ignore cache)
dotnet restore --force

Package Sources

List Sources

dotnet nuget list source

Add Private Feed

# Add authenticated feed
dotnet nuget add source https://pkgs.dev.azure.com/myorg/_packaging/myfeed/nuget/v3/index.json \
  --name MyFeed \
  --username az \
  --password $PAT \
  --store-password-in-clear-text

NuGet.config

For solution-specific sources, create NuGet.config:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <packageSources>
    <clear />
    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
    <add key="MyPrivateFeed" value="https://pkgs.dev.azure.com/myorg/_packaging/myfeed/nuget/v3/index.json" />
  </packageSources>
  <packageSourceCredentials>
    <MyPrivateFeed>
      <add key="Username" value="az" />
      <add key="ClearTextPassword" value="%NUGET_PAT%" />
    </MyPrivateFeed>
  </packageSourceCredentials>
</configuration>

Common Patterns

Development-Only Packages

<!-- Directory.Packages.props -->
<PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />

<!-- Project file - mark as development dependency -->
<PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All" />

Conditional Packages

<!-- Only include in Debug builds -->
<ItemGroup Condition="'$(Configuration)' == 'Debug'">
  <PackageReference Include="JetBrains.Annotations" />
</ItemGroup>

<!-- Platform-specific -->
<ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
  <PackageReference Include="System.Text.Json" />
</ItemGroup>

Version Override (Escape Hatch)

When you must override CPM for one project (rare):

<!-- Project file - use sparingly! -->
<PackageReference Include="Newtonsoft.Json" VersionOverride="12.0.3" />

Warning: This is detected by Slopwatch (see dotnet/slopwatch skill) as potential slop.


Troubleshooting

Version Conflicts

# See full dependency tree
dotnet list package --include-transitive

# Find what's pulling in a specific package
dotnet list package --include-transitive | grep -i "PackageName"

Restore Failures

# Clear all caches
dotnet nuget locals all --clear

# Restore with detailed logging
dotnet restore --verbosity detailed

# Check for locked packages
cat packages.lock.json

Lock Files

For reproducible builds, use package lock files:

<!-- Directory.Build.props -->
<PropertyGroup>
  <RestorePackagesWithLockFile>true</RestorePackagesWithLockFile>
</PropertyGroup>

Then commit packages.lock.json files.


Anti-Patterns

Don't: Edit XML Directly

<!-- BAD: Manual XML editing -->
<PackageReference Include="Typo.Package" Version="1.0.0" />
<!-- Package might not exist! CLI would catch this. -->

Don't: Inline Versions with CPM

<!-- BAD: Bypasses CPM -->
<PackageReference Include="Serilog" Version="4.0.0" />

<!-- GOOD: Version comes from Directory.Packages.props -->
<PackageReference Include="Serilog" />

Don't: Mix Version Management

<!-- BAD: Some versions in CPM, some inline -->
<PackageReference Include="Serilog" />  <!-- From CPM -->
<PackageReference Include="Newtonsoft.Json" Version="13.0.3" />  <!-- Inline -->

Don't: Forget Shared Variables

<!-- BAD: Related packages with different versions -->
<PackageVersion Include="Akka" Version="1.5.59" />
<PackageVersion Include="Akka.Cluster" Version="1.5.58" />  <!-- Mismatch! -->

<!-- GOOD: Use shared variable -->
<PackageVersion Include="Akka" Version="$(AkkaVersion)" />
<PackageVersion Include="Akka.Cluster" Version="$(AkkaVersion)" />

Quick Reference

TaskCommand
Add packagedotnet add package <name>
Add specific versiondotnet add package <name> --version <ver>
Remove packagedotnet remove package <name>
List packagesdotnet list package
Show outdateddotnet list package --outdated
Show vulnerabledotnet list package --vulnerable
Restoredotnet restore
Clear cachedotnet nuget locals all --clear

Resources

Individual skills in this repo

This repo contains 20 individual skills — each has its own dedicated page.

akka-hosting-actor-patterns

Patterns for building entity actors with Akka.Hosting - GenericChildPerEntityParent, message extractors, cluster sharding abstraction, akka-reminders, and ITimeProvider. Supports both local testing and clustered production modes.

akka-net-aspire-configuration

Configure Akka.NET with .NET Aspire for local development and production deployments. Covers actor system setup, clustering, persistence, Akka.Management integration, and Aspire orchestration patterns.

akka-net-best-practices

Critical Akka.NET best practices including EventStream vs DistributedPubSub, supervision strategies, error handling, Props vs DependencyResolver, work distribution patterns, and cluster/local mode abstractions for testability.

akka-net-management

Akka.Management for cluster bootstrapping, service discovery (Kubernetes, Azure, Config), health checks, and dynamic cluster formation without static seed nodes.

akka-net-testing-patterns

Write unit and integration tests for Akka.NET actors using modern Akka.Hosting.TestKit patterns. Covers dependency injection, TestProbes, persistence testing, and actor interaction verification. Includes guidance on when to use traditional TestKit.

api-design

Design stable, compatible public APIs using extend-only design principles. Manage API compatibility, wire compatibility, and versioning for NuGet packages and distributed systems.

aspire-configuration

Configure Aspire AppHost to emit explicit app config via environment variables; keep app code free of Aspire clients and service discovery.

aspire-integration-testing

Write integration tests using .NET Aspire

aspire-service-defaults

Create a shared ServiceDefaults project for Aspire applications. Centralizes OpenTelemetry, health checks, resilience, and service discovery configuration across all services.

crap-analysis

Analyze code coverage and CRAP (Change Risk Anti-Patterns) scores to identify high-risk code. Use OpenCover format with ReportGenerator for Risk Hotspots showing cyclomatic complexity and untested code paths.

csharp-concurrency-patterns

Choosing the right concurrency abstraction in .NET - from async/await for I/O to Channels for producer/consumer to Akka.NET for stateful entity management. Avoid locks and manual synchronization unless absolutely necessary.

database-performance

Database access patterns for performance. Separate read/write models, avoid N+1 queries, use AsNoTracking, apply row limits, and never do application-side joins. Works with EF Core and Dapper.

dependency-injection-patterns

Organize DI registrations using IServiceCollection extension methods. Group related services into composable Add* methods for clean Program.cs and reusable configuration in tests.

dotnet-devcert-trust

Diagnose and fix .NET HTTPS dev certificate trust issues on Linux. Covers the full certificate lifecycle from generation to system CA bundle inclusion, with distro-specific guidance for Ubuntu, Fedora, Arch, and WSL2.

dotnet-local-tools

Managing local .NET tools with dotnet-tools.json for consistent tooling across development environments and CI/CD pipelines.

dotnet-project-structure

Modern .NET project structure including .slnx solution format, Directory.Build.props, central package management, SourceLink, version management with RELEASE_NOTES.md, and SDK pinning with global.json.

dotnet-slopwatch

Use Slopwatch to detect LLM reward hacking in .NET code changes. Run after every code modification to catch disabled tests, suppressed warnings, empty catch blocks, and other shortcuts that mask real problems.

efcore-patterns

Entity Framework Core best practices including NoTracking by default, query splitting for navigation collections, migration management, dedicated migration services, and common pitfalls to avoid.

ilspy-decompile

Understand implementation details of .NET code by decompiling assemblies. Use when you want to see how a .NET API works internally, inspect NuGet package source, view framework implementation, or understand compiled .NET binaries.

mailpit-integration

Test email sending locally using Mailpit with .NET Aspire. Captures all outgoing emails without sending them. View rendered HTML, inspect headers, and verify delivery in integration tests.

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