Smithy Go

June 1, 2026 · View on GitHub

Smithy code generators for Go and the accompanying smithy-go runtime.

The smithy-go runtime requires a minimum version of Go 1.24.

WARNING: All interfaces are subject to change.

:warning: Client codegen is unstable

The client code generator in this repository powers the aws-sdk-go-v2. Arbitrary client generation, while technically possible, is in an early stage of development:

Generated clients are missing certain features that were originally implemented SDK-side (e.g. retries)
There may be bugs
The public APIs of generated clients may be unstable

If you are interested in using the client code generators, we encourage you to experiment and share any feedback with us in an issue.

Plugins

This repository implements the following Smithy build plugins:

ID	GAV prefix	Description
`go-codegen`	`software.amazon.smithy.go:smithy-go-codegen`	Implements Go client code generation for Smithy models.
`go-server-codegen`	`software.amazon.smithy.go:smithy-go-codegen`	Implements Go server code generation for Smithy models.
`go-shape-codegen`	`software.amazon.smithy.go:smithy-go-codegen`	Implements Go shape code generation (types only) for Smithy models.

NOTE: Build plugins are not currently published to mavenCentral. You must publish to mavenLocal to make the build plugins visible to the Smithy CLI. The artifact version is currently fixed at 0.1.0.

`go-codegen`

Configuration

GoSettings contains all of the settings enabled from smithy-build.json and helper methods and types. The up-to-date list of top-level properties enabled for go-client-codegen can be found in GoSettings::from().

Setting	Type	Required	Description
`service`	string	yes	The Shape ID of the service for which to generate the client.
`module`	string	yes	Name of the module in `generated.json` (and `go.mod` if `generateGoMod` is enabled) and `doc.go`.
`generateGoMod`	boolean		Whether to generate a default `go.mod` file. The default value is `false`.
`goDirective`	string		Go directive of the module. The default value is the minimum supported Go version.

Supported protocols

The protocol a client uses is configured by the Protocol field on a client's Options. The SDK will configure a default based on the protocol traits applied to the modeled service.

Protocol	Notes
`smithy.protocols#rpcv2Cbor`
`aws.protocols#restJson1`
`aws.protocols#restXml`
`aws.protocols#awsJson1_0`
`aws.protocols#awsJson1_1`
`aws.protocols#awsQuery`
`aws.protocols#ec2Query`

Example

This example applies the go-codegen build plugin to the Smithy quickstart example created from smithy init:

{
  "version": "1.0",
  "sources": [
    "models"
  ],
  "maven": {
    "dependencies": [
      "software.amazon.smithy.go:smithy-go-codegen:0.1.0"
    ]
  },
  "plugins": {
    "go-codegen": {
      "service": "example.weather#Weather",
      "module": "github.com/example/weather",
      "generateGoMod": true,
      "goDirective": "1.24"
    }
  }
}