Stainless has become the SDK generation platform of choice for leading API companies, producing the official client libraries used by developers integrating with Anthropic, OpenAI, Cloudflare, Lithic, and Modern Treasury. Unlike template-based generators that produce generic, boilerplate-heavy code, Stainless creates SDKs that feel hand-crafted — with idiomatic naming conventions, proper type definitions, comprehensive error types, and built-in reliability features like automatic retries with exponential backoff, configurable timeouts, and intelligent pagination.
The platform handles the full SDK lifecycle from generation through publishing. When an API specification changes, Stainless regenerates the affected SDK code, runs test suites against the live API, and can publish new package versions to npm, PyPI, Maven, and other registries through CI/CD integration. SDKs include streaming support for real-time APIs, file upload handling, webhook signature verification, and other complex patterns that are tedious to implement and maintain manually across multiple languages.
Stainless operates as a SaaS platform with API specification as input and published, versioned SDK packages as output. The generated code is the API provider's own — fully readable, customizable, and hosted in their repositories. For API companies where SDK quality directly impacts developer adoption and satisfaction, Stainless eliminates the ongoing maintenance burden of supporting SDKs in multiple languages while ensuring consistency across all client libraries as the API evolves.