Distributing Contracts

Distributing your Smithy model lets other projects consume it without copying files. There are two distribution paths:

• Maven JAR — any Smithy-based toolchain (Java, TypeScript, Python, and .NET) can consume it from a Maven registry, making it the more universal option.
• NuGet package — .NET consumers reference it like any other package; NSmithy picks up the model files and synthesizes a smithy-build.json automatically.

Maven JAR Distribution

Recommended

Maven JAR distribution is generally preferred — it works with any Smithy-based toolchain, not just .NET, so your model remains accessible to Java, TypeScript, Python, and other consumers without any extra steps.

Configure

Add SmithyMavenGroupId and SmithyMavenArtifactId to the contracts project:

<PropertyGroup>
  <SmithyPublish>true</SmithyPublish>
  <SmithyMavenGroupId>io.github.acme</SmithyMavenGroupId>
  <SmithyMavenArtifactId>my-service-contracts</SmithyMavenArtifactId>
</PropertyGroup>

Version (or VersionPrefix/VersionSuffix) is reused as the Maven version.

Pack

dotnet pack MyService.Contracts --configuration Release

When SmithyMavenGroupId is set, the _CreateSmithyJar MSBuild target runs after Pack and writes the JAR alongside the .nupkg:

bin/Release/
  MyService.Contracts.1.0.0.nupkg
  my-service-contracts-1.0.0.jar
  my-service-contracts-1.0.0.jar.md5
  my-service-contracts-1.0.0.jar.sha1
  my-service-contracts-1.0.0.pom
  my-service-contracts-1.0.0.pom.md5
  my-service-contracts-1.0.0.pom.sha1

The JAR follows Smithy’s model-discovery layout:

META-INF/smithy/
  manifest        ← newline-delimited list of model file paths
  hello.smithy    ← model file(s) from model/

Install Locally

To make the JAR available to a local Smithy CLI invocation during development:

mvn install:install-file \
  -Dfile=bin/Release/my-service-contracts-1.0.0.jar \
  -DpomFile=bin/Release/my-service-contracts-1.0.0.pom \
  -Dpackaging=jar

Publish to a Remote Registry

Use the dotnet-nsmithy push tool to upload to any Maven registry that accepts HTTP PUT (GitHub Packages, Artifactory, Nexus, etc.):

dotnet tool install -g dotnet-nsmithy

dotnet nsmithy push bin/Release \
  --registry https://maven.pkg.github.com/ORG/REPO \
  --username $GITHUB_ACTOR \
  --token    $GITHUB_TOKEN

push reads the Maven coordinates and version from the .csproj automatically. Credentials can also be supplied via MAVEN_USERNAME / MAVEN_TOKEN environment variables.

Note

Maven JAR distribution does not require a dedicated contracts project. You can add SmithyMavenGroupId, SmithyMavenArtifactId, and SmithyPublish=true directly to a server project that already owns its model files and dotnet pack will produce the JAR from there. That said, we still recommend splitting the model out into a separate contracts project — it keeps the model decoupled from any one implementation and makes it easier to share across server and client projects.

NuGet Distribution

Pack

dotnet pack MyService.Contracts --configuration Release

NSmithy.MSBuild embeds the model and dependency metadata into the package:

Package path	Contents
build/smithy/**/*.smithy	model files
build/smithy-maven-deps.txt	one Maven coordinate per line
build/NSmithy.MSBuild.props	sets SmithySources for consumers
buildTransitive/NSmithy.MSBuild.targets	MSBuild targets imported transitively

Consume

A project that references the published package picks up the model and Maven dependencies automatically — no ProjectReference needed:

<PropertyGroup>
  <SmithyService>example.hello#HelloService</SmithyService>
</PropertyGroup>

<ItemGroup>
  <PackageReference Include="NSmithy.Server.AspNetCore" Version="0.1.0-preview.15" />
  <PackageReference Include="MyService.Contracts" Version="1.0.0" />
</ItemGroup>

NSmithy synthesizes a smithy-build.json under obj/, invokes smithy build, and adds the generated .g.cs files to compilation — identical behaviour to a ProjectReference.