## dotnetCorePackages.sdk vs dotnetCorePackages.runtime vs dotnetCorePackages.aspnetcore {#dotnetcorepackages.sdk-vs-dotnetcorepackages.runtime-vs-dotnetcorepackages.aspnetcore}

The `dotnetCorePackages.sdk` contains both a runtime and the full sdk of a given version. The `runtime` and `aspnetcore` packages are meant to serve as minimal runtimes to deploy alongside already built applications.

## Packaging a Dotnet Application {#packaging-a-dotnet-application}

To package Dotnet applications, you can use `buildDotnetModule`. This has similar arguments to `stdenv.mkDerivation`, with the following additions:

* `projectFile` is used for specifying the dotnet project file, relative to the source root. These have `.sln` (entire solution) or `.csproj` (single project) file extensions. This can be a list of multiple projects as well. When omitted, will attempt to find and build the solution (`.sln`). If running into problems, make sure to set it to a file (or a list of files) with the `.csproj` extension - building applications as entire solutions is not fully supported by the .NET CLI.
* `nugetDeps` should be a path to a JSON file, a path to a nix file (deprecated), a derivation, or a list of derivations. A `deps.json` file can be generated using the script attached to `passthru.fetch-deps`, which is the preferred method. All `nugetDeps` packages are added to `buildInputs`.
::: {.note}
For more detail about managing the `deps.json` file, see [Generating and updating NuGet dependencies](#generating-and-updating-nuget-dependencies)
:::

* `packNupkg` is used to pack project as a `nupkg`, and installs it to `$out/share`. If set to `true`, the derivation can be used as a dependency for another dotnet project by adding it to `buildInputs`.
* `buildInputs` can be used to resolve `ProjectReference` project items. Referenced projects can be packed with `buildDotnetModule` by setting the `packNupkg = true` attribute and passing a list of derivations to `buildInputs`. Since we are sharing referenced projects as NuGets they must be added to csproj/fsproj files as `PackageReference` as well.
 For example, your project has a local dependency:
 ```xml
     <ProjectReference Include="../foo/bar.fsproj" />
 ```
 To enable discovery through `buildInputs` you would need to add:
 ```xml
     <ProjectReference Include="../foo/bar.fsproj" />
     <PackageReference Include="bar" Version="*" Condition=" '$(ContinuousIntegrationBuild)'=='true' "/>
  ```
* `executables` is used to specify which executables get wrapped to `$out/bin`, relative to `$out/lib/$pname`. If this is unset, all executables generated will get installed. If you do not want to install any, set this to `[]`. This gets done in the `preFixup` phase.
* `runtimeDeps` is used to wrap libraries into `LD_LIBRARY_PATH`. This is how dotnet usually handles runtime dependencies.
* `buildType` is used to change the type of build. Possible values are `Release`, `Debug`, etc. By default, this is set to `Release`.
* `selfContainedBuild` allows to enable the [self-contained](https://docs.microsoft.com/en-us/dotnet/core/deploying/#publish-self-contained) build flag. By default, it is set to false and generated applications have a dependency on the selected dotnet runtime. If enabled, the dotnet runtime is bundled into the executable and the built app has no dependency on .NET.
* `useAppHost` will enable creation of a binary executable that runs the .NET application using the specified root. More info in [Microsoft docs](https://learn.microsoft.com/en-us/dotnet/core/deploying/#publish-framework-dependent). Enabled by default.
* `useDotnetFromEnv` will change the binary wrapper so that it uses the .NET from the environment. The runtime specified by `dotnet-runtime` is given as a fallback in case no .NET is installed in the user's environment. This is most useful for .NET global tools and LSP servers, which often extend the .NET CLI and their runtime should match the users' .NET runtime.
* `dotnet-sdk` is useful in cases where you need to change what dotnet SDK is being used. You can also set this to the result of `dotnetSdkPackages.combinePackages`, if the project uses multiple SDKs to build.