Senior Software Engineer (SDK)

About the Role

Join a fast-growing open-source LLM observability platform — often described as the Datadog of AI — and own the SDKs that millions of developers rely on every month. The SDK is the very first touchpoint developers have with the platform, and your work ships to thousands of users the same day. This is a high-ownership, high-impact role at a company that has scaled to enterprise customers across the Fortune 50.

The platform processes over 10 billion observations per month, supports 80+ integrations, and is trusted by thousands of production AI teams. It is now part of a major analytics infrastructure company, bringing additional scale and resources.

What You'll Do

• Own Python and TypeScript SDKs — reliability, performance, and developer experience end-to-end, including rewrites and major version migrations (e.g. OpenTelemetry-based architectures).
• Design APIs developers love — naming conventions, parameter structure, breaking change communication, and documentation.
• Optimize for production environments — SDKs must run reliably from serverless functions to long-running agent loops with minimal CPU and memory overhead.
• Manage the full SDK lifecycle — versioning, packaging, release automation, compatibility testing, and CI/CD pipelines.
• Engage with the open-source community — triage GitHub issues, review PRs, respond to developer questions, and maintain a public presence across developer channels.
• Collaborate cross-functionally with product and data teams to shape the observability and tracing experience across the platform.

What We're Looking For

Required:

• 5+ years of professional software engineering experience, including at least 2 years building or maintaining SDKs or client libraries.
• Proven track record designing, implementing, and maintaining production-grade SDKs — API design, versioning, packaging, and release management.
• Experience optimizing SDK/library performance: profiling, reducing latency and memory usage, improving throughput.
• Hands-on experience with observability, tracing, metrics, or monitoring systems (e.g. OpenTelemetry or similar).
• Proficiency in at least one SDK language: Python, TypeScript/JavaScript, Go, or Java — with the ability to write idiomatic, production-quality code.
• Experience contributing to and maintaining open-source projects, including community interactions via GitHub.
• Strong written and verbal communication skills; comfortable writing documentation and engaging publicly with developers.
• Experience with automated testing and CI/CD pipelines for libraries (unit/integration testing, release automation, compatibility testing).
• Ability to work effectively in a small, distributed engineering team across EU timezones.
• Legal authorization to work in the EU is required — no visa sponsorship available.
• Ability to be onsite in Berlin at least one week per month.

Nice to Have:

• Familiarity with analytics or large-scale telemetry systems (e.g. OLAP/columnar databases such as ClickHouse).
• Bachelor's degree in Computer Science, Engineering, or equivalent practical experience.

Compensation & Benefits

• Salary range: $90,000 – $160,000 USD annually (or equivalent, depending on location)
• Equity and competitive benefits package
• Work in a small, senior engineering team with a strong open-source culture

Location

This is a hybrid remote role. You can be based anywhere in the EU (Germany, Austria, Switzerland, Netherlands, France, Spain, Sweden, Poland, UK, and more) with the expectation of spending approximately one week per month in Berlin. EU work authorization is required.