Senior SDK Engineer - Platform Enablement

Auction Technology Group (ATG) builds online auction technology connecting auction houses and buyers. The Senior SDK Engineer will design and maintain Python and Go libraries and developer tools used across ATG’s distributed services, embedding reliability and observability while improving developer velocity.

Responsibilities:

• Design, build, and maintain Python and Go SDKs used across ATG’s distributed systems, with a consistent developer experience across both languages
• Bake resiliency patterns such as retries, timeouts, circuit breakers, backpressure, graceful degradation, idempotency directly into the libraries so individual services don’t have to reinvent them
• Build first-class observability into the SDKs: structured logging, distributed tracing, and metrics instrumentation that “just works” out of the box for any service built on top
• Design clean, well-documented, versioned APIs and contracts, with an eye toward backward compatibility and safe rollout across many consuming services
• Drive developer velocity: reduce boilerplate, improve local development and testing ergonomics, and shorten the time from “new service” to “in production”
• Write comprehensive unit, integration, and contract tests, and build testing utilities/mocks that make the SDKs easy for other teams to test against
• Partner with service teams to understand real usage patterns, pain points, and failure modes, and feed that directly back into SDK design
• Own the release process for the libraries with versioning, changelogs, deprecation policy, and migration paths for breaking changes
• Build internal documentation, examples, and onboarding materials that let engineers self-serve adoption of the SDKs
• Participate in code reviews, architectural discussions, and design reviews across the teams that consume these libraries
• Debug and resolve issues that span the SDK and the distributed systems built on top of it
• Mentor other engineers on distributed systems fundamentals and SDK/library design

Requirements:

• 5+ years of professional software engineering experience, including designing and maintaining libraries, SDKs, or shared platform components used by other engineering teams
• Strong proficiency in both Python and Go, with production experience building and maintaining public-facing (internal or external) APIs/libraries in each
• Deep understanding of distributed systems fundamentals: consistency, partial failure, retries and idempotency, timeouts, backpressure, and consensus/coordination basics
• Experience designing resiliency patterns (circuit breakers, retries with backoff/jitter, bulkheads, graceful degradation) and building them into reusable components
• Hands-on experience instrumenting systems for observability — structured logging, distributed tracing (e.g. OpenTelemetry), and metrics (e.g. Prometheus)
• Strong API design sensibility: versioning strategy, backward compatibility, deprecation, and clear documentation
• Experience with the packaging, versioning, and distribution mechanics of Python (pip/PyPI) and Go (Go modules) libraries
• Proficiency with Git and CI/CD (e.g. GitHub Actions) for automated testing, versioning, and publishing of libraries
• Experience with message queues or event-driven systems (RabbitMQ, Kafka, AWS SQS/SNS) and/or RPC frameworks (gRPC, protocol buffers)
• Familiarity with containerization (Docker) and orchestration (Kubernetes/EKS) as deployment targets for services built on the SDKs
• Strong testing discipline: unit, integration, and contract testing, plus experience building test doubles/mocks for library consumers
• Strong problem-solving skills with the ability to reason about failure modes across many consuming services at once
• A product mindset toward internal tooling; you treat other engineers as your customers and care about their experience
• Excellent written communication skills; comfortable writing documentation, RFCs, and migration guides that other engineers actually read
• Comfortable working cross-functionally with Architecture, Platform Enablement, Data Engineering, and product engineering teams
• Strong track record of driving adoption of shared tooling through good design rather than mandate
• Proactive about identifying friction, inconsistency, and technical debt across the platform and turning it into SDK improvements
• Collaborative, low-ego approach to giving and receiving feedback on API and library design
• Ability to balance long-term platform investment with near-term velocity needs of consuming teams
• Experience building or maintaining an open-source library with external consumers
• Experience with schema/contract tools (protobuf, OpenAPI, JSON Schema) and code generation
• Familiarity with service mesh technologies (Istio, Linkerd) and their relationship to SDK-level resiliency
• Experience with feature flagging, progressive delivery, or canary/rollout tooling
• Background in high-traffic, real-time, or marketplace/auction platforms
• Experience with performance profiling and benchmarking in Python and/or Go
• Familiarity with distributed tracing backends such as Jaeger, Tempo, Honeycomb and Grafana/Loki/Prometheus stacks
• Contributions to well-known open-source SDKs or client libraries