'dotnet publish' uses Release configuration

Article
02/08/2023

The dotnet publish command now uses the Release configuration instead of the Debug configuration by default if the target framework is .NET 8 or a later version.

Previous behavior

Previously, dotnet publish used the Debug configuration unless the configuration was specified explicitly or PublishRelease was set to true.

The PublishRelease property was added in .NET 7 as a path forward to this breaking change. Previously, you could set the DOTNET_CLI_ENABLE_PUBLISH_RELEASE_FOR_SOLUTIONS environment variable to use PublishRelease in a project that was part of a Visual Studio solution.

New behavior

If you're developing with the .NET 8 SDK or a later version, dotnet publish uses the Release configuration by default for projects whose TargetFramework is set to net8.0 or a later version. If you have a CI/CD script, tests, or code where you've hardcoded Debug into an output path, this change may break your workflow.

If your project targets multiple versions, the new behavior only applies if you specify a target framework of .NET 8 or later when you publish (for example, using dotnet publish -f net8.0).

For projects in a solution:

dotnet publish can publish all the projects in a Visual Studio solution if given a solution file. For the solution projects that target .NET 8 or later, the value of PublishRelease is implicitly set to true if it's undefined. However, in order for dotnet publish to determine the correct configuration to use for the solution, all projects in the solution must agree on their value of PublishRelease. If an older project in the solution has PublishRelease set to false, you should explicitly set the property to false for any new .NET 8+ projects as well.
This change might cause the performance of dotnet publish to regress, especially for solutions that contain many projects. To address this, a new environment variable DOTNET_CLI_LAZY_PUBLISH_AND_PACK_RELEASE_FOR_SOLUTIONS has been introduced.
The DOTNET_CLI_ENABLE_PUBLISH_RELEASE_FOR_SOLUTIONS environment variable is no longer recognized.

Version introduced

.NET 8 Preview 1

Type of breaking change

This change can affect source compatibility and is also a behavioral change.

Reason for change

In most cases when you publish, you want your code to be optimized and can keep the app smaller by excluding debugging information. Customers have asked for Release to be the default configuration for publish for a long time. Also, Visual Studio has had this behavior for many years.

The DOTNET_CLI_ENABLE_PUBLISH_RELEASE_FOR_SOLUTIONS environment variable was removed since the behavior it enabled is now the default behavior and the granular control is no longer necessary.

Recommended action

To disable the new behavior entirely, you can set the DOTNET_CLI_DISABLE_PUBLISH_AND_PACK_RELEASE environment variable to true (or any other value). This variable affects both dotnet publish and dotnet pack.
To explicitly specify the Debug configuration for publishing, use the -c or --configuration option with dotnet publish.
If your CI/CD pipeline is broken due to hardcoded output paths, update the paths to Release instead of Debug, disable the new behavior using the DOTNET_CLI_DISABLE_PUBLISH_AND_PACK_RELEASE environment variable, or specify that the Debug configuration should be used.
If you're publishing a solution and it's broken, you can explicitly set PublishRelease to true (or false to revert to the previous behavior).
```
<PropertyGroup>
  <PublishRelease>true</PublishRelease>
</PropertyGroup>
```
Alternatively, you can specify the property in a Directory.Build.Props file. However, if you set it false in this file, you'll still need to explicitly set the property to false in the .NET 8+ projects in the solution. Similarly, if some projects explicitly set a value that's different from the value in the Directory.Build.Props file, publish will fail.
If you're publishing a solution and the performance has regressed, you can set the DOTNET_CLI_LAZY_PUBLISH_AND_PACK_RELEASE_FOR_SOLUTIONS environment variable to true (or any other value) to remove the regression. However, if you set this variable and your solution contains a .NET 8+ project and a project that targets .NET 7 or earlier, publishing will fail until all projects define PublishRelease. This variable affects both dotnet publish and dotnet pack.

Share via