smithy-lang/smithy

Health v2 · maintenance only

Adoption not part of the score

2345 stars · 257 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

Smithy is a protocol-agnostic interface definition language (IDL) and a set of tools for modeling services as collections of resources, operations, and shapes. From a single model, it generates type-safe clients, servers, documentation, and OpenAPI/JSON Schema artifacts across many programming languages, and it powers the APIs and SDKs at AWS.

Use cases

• define an API once and generate client SDKs in multiple languages
• generate server scaffolding and API documentation from a service model
• convert Smithy models to OpenAPI or JSON Schema
• model services protocol-agnostically and switch wire protocols without changing the model
• build and validate Smithy models with the Smithy CLI
• generate AWS-style SDKs for custom services

When to choose

• you need multi-language client/server code generation from a single API definition
• you want protocol-agnostic API modeling with extensible traits
• you build AWS SDKs or AWS-compatible services
• you need normalized, diffable, machine-traversable API models

When to avoid

• you need a lightweight REST API without code generation overhead
• your team is already invested in OpenAPI-first or GraphQL workflows
• you only target a single language and a simple hand-written client suffices

Facets

framework · maturity stable

api-framework sdk documentation cli build-tool developer-tools apis web-development backend jvm cross-platform cli idl interface-definition-language api-modeling code-generation openapi aws protocol-agnostic smithy

Member repositories

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