December 2025 Summaries

Stainless is committed to revolutionizing API development by transforming accumulated experience into versatile tools for API teams, striving to alleviate common challenges like client library maintenance, documentation management, and API feature debates. The company has enhanced its SDK generator to support new languages like Java, Kotlin, and PHP, improved existing generators for Go and TypeScript, and introduced Terraform provider generation to streamline resource provisioning. Stainless also launched a Docs Platform that keeps API documentation synchronized with evolving APIs and developed an MCP server to facilitate API integration with AI agents. In 2025, Stainless expanded its team significantly and focused on preparing for a future where AI agents will interact more with APIs than traditional software interfaces, emphasizing the need for robust APIs to ensure seamless AI integration. Looking ahead to 2026, Stainless plans to advance its product offerings to support API teams in scaling their operations and adapting to the growing role of AI in software usage.

OpenAPI specifications often face subtle compatibility issues when generating SDKs, such as type mismatches, naming collisions, and structural issues, which cannot be easily fixed by upstream teams. Stainless Transforms offer a solution by allowing modifications to the OpenAPI spec without changing the original source file. These transforms are defined in a configuration file and automatically applied, providing a transformed version of the spec that is explicit and reviewable. The system introduces a range of composable functions for tasks like updating, appending, merging, removing, copying, and moving components within a spec, addressing common real-world issues and improving SDK alignment with actual APIs. Unlike OpenAPI Overlays, which handle lightweight patches, Transforms support more complex operations such as schema deduplication, language-aware naming, and fail-fast validation, offering a robust approach to manage SDK and documentation pipelines. Additionally, Transforms facilitate schema-based targeting and support string interpolation for modifying existing values, enabling more efficient handling of auto-generated specs and preventing the silent drift that can occur with Overlays. Overall, Stainless Transforms provide a more structured and diagnostic-friendly approach to managing OpenAPI specs, enhancing the reliability and maintainability of SDKs.

APIs can significantly enhance business growth and awareness by attracting developers who, although not the primary audience, play a crucial role in decision-making and product utilization. Making APIs appealing to developers can open up new growth avenues, as developers often influence technical decisions, extend product reach, and advocate for products they appreciate. To effectively engage developers, it's essential to offer a well-designed API, idiomatic SDKs, comprehensive documentation, and an MCP server, as these elements collectively enhance the development experience. However, achieving this requires careful consideration of resources, as there are various approaches such as relying on community contributions, hiring contractors, building in-house, using free generators, or partnering with API companies. Each option comes with its own set of requirements, risks, and growth potential, making it crucial to align the choice with the organization's specific needs and future growth strategies.

API platform teams often face the dilemma of whether to hand-write SDKs or use an SDK generator like Stainless, with the decision largely hinging on whether the SDK primarily wraps an HTTP API or implements business logic. Generators are recommended when the SDK involves REST API integration, requires robust HTTP handling, type safety, and multi-language support, while hand-writing is better suited for SDKs that focus on business logic without a corresponding API specification. Using a generator, especially with an OpenAPI specification, provides a single source of truth that ensures consistency and type safety across client codebases, while also addressing challenges like drift, performance, and reliability. Despite common objections about complexity and readabilty, modern generators like Stainless produce idiomatic and human-readable code, facilitating easier updates and multi-language support. A hybrid approach, which involves generating the networking layer and crafting high-level helpers, offers a balanced solution, allowing teams to focus on differentiating backend services while maintaining flexibility and minimizing the need for bespoke libraries.