speakeasy-api/speakeasy

Build APIs your users love ❤️ with Speakeasy. ✨ Polished and type-safe SDKs. 🌐 Terraform providers, MCP servers, CLIs and Contract Tests for your API. OpenAPI native.

What it solves

Speakeasy provides a modern toolchain for API developers to automate the creation of high-quality, type-safe client SDKs, Terraform providers, and contract tests. It eliminates the manual effort of writing and maintaining these assets across multiple programming languages as an API evolves.

How it works

Speakeasy uses OpenAPI 3.X specifications as the source of truth. It provides a set of tools for linting, cleaning, and editing these specs (via Overlays) and then generates polished, idiomatic code for SDKs in 10+ languages, Terraform providers, and contract tests powered by Arazzo.

Who it’s for

API providers and developers who need to distribute their API to users in multiple languages (e.g., TypeScript, Python, Go, Java, C#, PHP, Ruby, Unity) and ensure their API contracts are strictly validated.

Highlights

  • Multi-language SDKs: Generates idiomatic, type-safe code for over 10 languages.
  • Terraform Providers: Automatically builds complete Terraform providers based on a type-safe Go SDK.
  • Contract Testing: Generates contract tests with a pre-built mock server.
  • OpenAPI Tooling: Includes a toolchain for linting, diffing, and editing OpenAPI specs.
  • AI Agent Integration: Offers "Agent Skills" to allow AI coding agents (like Claude Code, Cursor, and GitHub Copilot) to manage SDK projects and validate specs.

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