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.
SKILL.md
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dotnet list package --outdated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.
# 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:
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
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
