Software Engineer, SDK
Builds and maintains multi-language SDK libraries for Keycard's agent control plane, ensuring compatibility across frameworks and deployments. Requires systems engineering expertise, multi-language proficiency, and agent ecosystem knowledge.
About the job
Responsibilities
- Build and own the Keycard Agent SDK libraries across languages (Go, Python, TypeScript, Rust).
- Maintain compatibility with upstream agent frameworks and deployment patterns (cloud, edge, hybrid).
- Contribute to open protocol work (MCP, A2A).
- Advocate for agent developers' needs and work with founders, product, and systems engineers.
Requirements
- Follow the agent ecosystem closely and build with these tools.
- Strong systems engineering instincts: write tests, ensure backwards compatibility, version correctly, care about API surface area.
- Experience building libraries or SDKs that other developers depend on.
- Work across multiple languages without treating any as second-class.
Nice-to-Haves
- Experience with plugin systems, provider architectures, or marketplace/ecosystem engineering (Terraform providers, VS Code extensions, Stripe integrations).
- Contributions to open source agent frameworks or protocols.
- Background in identity/auth protocols (OIDC, OAuth, mTLS) at the library level.
- Experience with code generation tools (OpenAPI, protobuf, smithy) for multi-language SDK maintenance.
Compensation & Benefits
- Market-competitive salaries and generous equity packages (4-year vest, 1-year cliff).
- Comprehensive health, dental, vision, and paramedical coverage.
- 4 weeks vacation, 11 statutory holidays, 1 volunteer day.
- New MacBook Pro, $500 peripherals stipend, best AI tools.
- Remote-first flexibility.
Skills
Go, Python, TypeScript, Rust, Sdk Development, Agent Frameworks, OAuth, OIDC, Mtls, Openapi, Protobuf, Terraform, Open Source Contributions
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