Self‑Contained .NET Application with Dynamic Library Version

This README explains how to publish a .NET application as a self‑contained, single‑file executable, target multiple frameworks, and override library versions at build/runtime. It also breaks down each CLI flag and MSBuild parameter.

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What is a Self‑Contained Application?

A self‑contained deployment bundles your app and the entire .NET runtime into the output folder. This means the target machine does not need to have .NET installed. You get:

• The application executable (or single file if you bundle).
• All framework libraries and runtime components.

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Prerequisites

• .NET SDK installed on your machine
• Your project uses the SDK‑style .csproj format
• (Optional) A multi‑targeted project if you need to support multiple frameworks

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Project Configuration

In your .csproj, you can set up multi‑targeting, default library version, and runtime identifiers. Example:

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <!-- Multi-target frameworks -->
    <TargetFrameworks>net9.0;net8.0</TargetFrameworks>

    <!-- Default library version; can be overridden -->
    <LibraryVersion>6.0.16</LibraryVersion>

    <!-- Nullable and implicit usings -->
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>

    <!-- Supported runtime environments -->
    <RuntimeIdentifiers>win-x64;linux-x64</RuntimeIdentifiers>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite"
                      Version="$(LibraryVersion)" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design"
                      Version="$(LibraryVersion)"
                      PrivateAssets="all" />
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.2.3" />
  </ItemGroup>
</Project>

• TargetFrameworks: list of frameworks you want to compile for.
• LibraryVersion: a custom MSBuild property for your NuGet package version.
• RuntimeIdentifiers: RIDs for each platform you want to deploy to.

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Publishing the Application

Basic Publish Command

From your project directory (next to MyApp.csproj), run:

dotnet publish MyApp.csproj \
  -c Release \
  -r linux-x64 \
  --self-contained true \
  -o ./publish/linux-x64

This produces a self‑contained folder under ./publish/linux-x64 containing:

• Your app executable (MyApp)
• All framework DLLs
• The .NET runtime

Targeting Specific Frameworks

If you multi‑target, specify -f / --framework:

dotnet publish MyApp.csproj \
  -c Release \
  -r linux-x64 \
  -f net8.0 \
  --self-contained true \
  -o ./publish/linux-x64-net8

That picks the net8.0 target and builds only that.

Overriding LibraryVersion at Runtime

Override MSBuild properties on the CLI with -p: (short for --property:):

# Override the LibraryVersion property
dotnet publish MyApp.csproj \
  -c Release -r linux-x64 -f net8.0 \
  -p:LibraryVersion=7.0.0-preview \
  --self-contained true \
  -o ./publish/linux-x64-net8-preview

Alternatively, set the environment variable (MSBuild imports all env‑vars):

export LibraryVersion=7.1.2
dotnet publish MyApp.csproj -c Release -r linux-x64 -f net8.0

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Explanation of Flags & Parameters

Flag / Parameter	Description
MyApp.csproj	Path to your project file; you can omit if you’re in the same directory and there’s only one .csproj.
-c Release / --configuration	Build configuration; Release enables optimizations, Debug includes debug symbols.
-r linux-x64 / --runtime	Target Runtime Identifier (RID) for the platform you’re publishing to (e.g., win-x64, linux-arm64).
-f net8.0 / --framework	Target framework when multi‑targeting (e.g., net7.0, net8.0, netstandard2.0).
--self-contained true	Packages the .NET runtime and framework libraries so the app can run on machines without .NET installed.
/p:PublishSingleFile=true	Bundle app and dependencies into a single executable file (on Windows .exe, Linux a native ELF binary).
/p:PublishTrimmed=true	Trims unused IL to reduce final binary size; may require explicit trimmer roots for reflection-heavy libraries.
/p:PublishReadyToRun=true	Ahead‑of‑time (AOT) compile native code to improve startup performance.
-p:LibraryVersion=<version>	Overrides your custom LibraryVersion MSBuild property to pull a different NuGet package version at build time.
-o ./publish/... / --output	Overrides the default output directory for published files.

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Conditional Package References

To pull different package versions per framework, use MSBuild conditions:

<PropertyGroup Condition="'$(TargetFramework)'=='net8.0'">
  <LibraryVersion>6.0.16</LibraryVersion>
</PropertyGroup>
<PropertyGroup Condition="'$(TargetFramework)'=='net9.0'">
  <LibraryVersion>7.0.0-preview</LibraryVersion>
</PropertyGroup>

<ItemGroup>
  <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite"
                    Version="$(LibraryVersion)" />
</ItemGroup>

When you run dotnet publish -f net8.0 it uses EF 6.0.16; with -f net9.0 it uses EF 7.0.0-preview.

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Examples

Publish for Linux x64 on .NET 8 (default version)

dotnet publish MyApp.csproj -c Release -r linux-x64 -f net8.0 --self-contained true -o ./publish/linux-x64

Publish for Windows x64 on .NET 9 with preview EF

dotnet publish MyApp.csproj -c Release -r win-x64 -f net9.0 \
  -p:LibraryVersion=7.0.0-preview \
  --self-contained true \
  /p:PublishSingleFile=true \
  /p:PublishTrimmed=true \
  /p:PublishReadyToRun=true \
  -o ./publish/win-x64-net9-preview

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