0.8.0 · Preview

Configuration

Configure the generator with MSBuild properties in your consuming project’s .csproj, or in a shared Directory.Build.props when several projects should use the same settings.

Property	Default	Supported values
`AvroSourceGeneratorAccessModifier`	`public`	`public`, `internal`
`AvroSourceGeneratorRecordDeclaration`	Records when supported	`record`, `class`
`AvroSourceGeneratorLanguageFeatures`	`All`, limited by the project’s C# version	`CSharp7_3`, `CSharp8`, `CSharp9`, `CSharp10`, `CSharp11`, `CSharp12`, `CSharp13`, `CSharp14`, `CSharp15`, `All`
`AvroSourceGeneratorAvroLibrary`	`Auto`	`Auto`, `None`, `Apache`
`AvroSourceGeneratorDuplicateResolution`	`Error`	`Error`, `Ignore`
`AvroSourceGeneratorReferenceResolution`	`Strict`	`Strict`, `Deferred`
`AvroSourceGeneratorPreviewFeatures`	`None`	`None`, `Unions`

Chr support is removed in the next 0.8.0 preview. Explicit Chr settings or automatic Chr detection report AVROSG6002 and generate standalone fallback models. See migration guidance.

Access modifier

Generate types that are visible only within your assembly:

<PropertyGroup>
  <AvroSourceGeneratorAccessModifier>internal</AvroSourceGeneratorAccessModifier>
</PropertyGroup>

Records or classes

Use classes when that better fits your application:

<PropertyGroup>
  <AvroSourceGeneratorRecordDeclaration>class</AvroSourceGeneratorRecordDeclaration>
</PropertyGroup>

By default, records are used when supported by the selected feature set and runtime target. Some schema kinds require classes because of inheritance constraints.

Language features

Usually, leave this unset and let the generator follow your project’s C# version. You can choose a reduced set of generated features without changing your application’s SDK:

<PropertyGroup>
  <AvroSourceGeneratorLanguageFeatures>CSharp10</AvroSourceGeneratorLanguageFeatures>
</PropertyGroup>

For example, this avoids generating required properties. A feature-set value controls generated syntax; it does not install a compiler or change the project’s LangVersion. Choose a feature set your compiler supports.

Library selection

Force Apache.Avro when both supported libraries are referenced:

<PropertyGroup>
  <AvroSourceGeneratorAvroLibrary>Apache</AvroSourceGeneratorAvroLibrary>
</PropertyGroup>

Choose None to generate standalone models without a no-library warning. See Avro libraries for installation and detection behavior.

Duplicate resolution

Duplicates normally produce errors. When duplicate declarations across files are intentional, you can keep the first declaration in the supplied file order:

<PropertyGroup>
  <AvroSourceGeneratorDuplicateResolution>Ignore</AvroSourceGeneratorDuplicateResolution>
</PropertyGroup>

With Ignore, input order determines the selected definition. Use this only when that choice is safe. Duplicate declarations within a single file and equivalent source paths remain errors.

The default Error reports the duplicate and suppresses affected files. Independent valid files still generate.

Reference resolution

Choose deferred binding for related types declared in separate JSON input files:

<PropertyGroup>
  <AvroSourceGeneratorReferenceResolution>Deferred</AvroSourceGeneratorReferenceResolution>
</PropertyGroup>

Strict requires an earlier declaration in the same file or a declaration in its transitive IDL import closure. Deferred resolves references after all supported inputs are read. Import paths are validated in either mode. See Schemas and imports for examples.

C# union types

To opt into native C# union types, set AvroSourceGeneratorPreviewFeatures to Unions and use .NET 11 with LangVersion=preview. If you set a language feature set, choose CSharp15 or All. See native C# unions for the complete setup and limitations.