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KeycardKeycardUnited States

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.

Salary not listed
RemoteBackend Engineering

About the role

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

GoPythonTypeScriptRustSdk DevelopmentAgent FrameworksOAuthOIDCMtlsOpenapiProtobufTerraformOpen Source Contributions

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