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Automatic RuntimeIdentifier for certain projects

  • Article

Projects that specify any of the following properties now get a runtime identifier (RID) automatically. An RID enables publishing a self-contained deployment.

  • SelfContained
  • PublishAot
  • PublishReadyToRun
  • PublishSingleFile
  • PublishSelfContained (.NET SDK 7.0.200 and later versions only)

The following projects might be affected by this change:

  • Old projects that circumvented the missing runtime identifier error.
  • Projects that have RuntimeIdentifiers but not RuntimeIdentifier.
  • Projects that use hard-coded paths without RIDs.
  • Projects that had these properties but used a build instead of a publish and accepted publish being in a broken state.

There are other potential nuances that could break individual situations that we're not yet aware of.

Note

This change was restricted to the dotnet publish command in .NET 7.0.200 SDK. For more information, see Automatic RuntimeIdentifier for publish only.

Version introduced

.NET 7

Previous behavior

Previously, these projects failed to publish with errors such as:

It is not supported to publish an application to a single-file without specifying a RuntimeIdentifier. Please either specify a RuntimeIdentifier or set PublishSingleFile to false.

OR

error NETSDK1031: It is not supported to build or publish a self-contained application without specifying a RuntimeIdentifier. You must either specify a RuntimeIdentifier or set SelfContained to false.

In some cases, such as PublishSingleFile or with special RuntimeIdentifiers logic, projects might have built successfully without a RuntimeIdentifier.

New behavior

Projects that specify any of the properties listed at the beginning of this article get a RuntimeIdentifier automatically. This new behavior can cause build failures on projects that rely on RuntimeIdentifiers but not RuntimeIdentifier, because RuntimeIdentifier can affect the output path distinctly from RuntimeIdentifiers. It can also cause failures on AnyCPU projects that rely on PublishSingleFile but don't always give a RuntimeIdentifier when taking other actions. These failures can appear as follows:

The target process exited without raising a CoreCLR started event. Ensure that the target process is configured to use .NET Core.

Type of breaking change

This change can affect source compatibility.

Reason for change

A majority of .NET projects fail to publish using the mentioned properties without RuntimeIdentifier set. This change reduces the need to add the RID manually every time you use the mentioned properties.

If your project is impacted, you can disable the automatic RuntimeIdentifier by adding <UseCurrentRuntimeIdentifier>false</UseCurrentRuntimeIdentifier> to your project file.

If you encounter a break due to the output path changing, add <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath> to your project file.

See also