Keycard
Software Engineer, SDK
US - Remote +1 · Remote · Full-time · Posted Oct 26, 2026
- Location
- US - Remote
Canada - Remote
About the job
Own and improve Keycard’s developer SDKs, keeping authentication behavior consistent across languages while managing integrations, generated clients, releases, and developer documentation.
What you'll do
- Design consistent, idiomatic APIs across Python, TypeScript, Go, and Ruby, with secure token validation and refresh behavior.
- Maintain upstream MCP and framework compatibility; manage package versioning, publishing, generated clients, and CI.
- Improve developer experience through quick starts, examples, documentation, and feedback-driven API changes.
What they ask for
- Shipped libraries or SDKs used by other developers and supported them through breaking changes.
- Maintained a consistent API across at least two languages; writes idiomatic Python and TypeScript.
- Knows OAuth 2.0 and OIDC at the library level, including token verification, refresh, PKCE, and token exchange (RFC 8693).
- Managed real-world versioning, including peer dependency ranges, maintenance branches, and planned deprecations; built framework integrations or protocol libraries and can work through MCP authorization flows and compatibility changes.
Nice to have
- Multi-language SDK code generation using Stainless, Speakeasy, Fern, OpenAPI, or protobuf; plugin or integration ecosystems.
- Contributions to MCP, A2A, or open-source agent frameworks; experience with Cloudflare Workers or Temporal.
Tools
Python, TypeScript, Go, Ruby, MCP, OpenAPI, FastMCP, LangChain
AI focus
Build SDKs and integrations for agent identity, credential exchange, delegation, policy, and audit; use coding agents in SDK development and determine appropriate trust boundaries and review safeguards.
Model-written summary · the original posting is authoritative