Senior Fullstack Engineer - Observability Real User Monitoring (RUM) | US | Remote

What you’ll be doing

• Build and evolve fullstack features for RUM, spanning backend services, APIs, storage systems, and frontend user experiences.
• Design and implement systems that ingest, store, and query high-cardinality, high-volume telemetry data using columnar/analytical databases.
• Develop performant query layers and APIs that power real-time exploration of user sessions, traces, and events.
• Contribute to frontend applications that visualize RUM data, enabling users to debug performance issues and understand user behavior.
• Work on data modeling, indexing strategies, and query optimization to ensure low-latency, cost-efficient analytics at scale.
• Collaborate closely with SDK engineers (browser and mobile) to ensure high-quality data ingestion and schema evolution.
• Own projects end-to-end: from design and implementation to deployment, monitoring, and iteration.
• Break down complex, ambiguous problems into incremental deliverables and iterate quickly based on feedback.
• Ensure quality through testing, observability of your own systems, documentation, and smooth upgrade paths.
• Collaborate cross-functionally with backend, frontend, product, and solutions engineering to deliver cohesive observability workflows.
• Support teammates, participate in technical design discussions and help shape the RUM roadmap.

What makes you a great fit

• 5+ years of fullstack engineering experience with strong backend fundamentals
• Backend experience (Go is preferred) and frontend experience, we use TypeScript and React
• Experience building or operating distributed systems in production (e.g., Kafka, WarpStream, ClickHouse, Cassandra, Postgres)
• Familiarity with cloud-native systems (Docker, Kubernetes, AWS, GCP, Azure)
• Experience working with high-throughput, high-cardinality data (logs, metrics, traces, events)
• Strong understanding of data modeling, query optimization, and performance tradeoffs
• Experience designing and building APIs and distributed services
• Experience building data-heavy UIs (dashboards, query tools, debugging interfaces)
• Familiarity with observability concepts (traces, logs, metrics) and/or OpenTelemetry
• Strong communication skills and ability to work in a remote, distributed team
• Pragmatic, self-driven, and comfortable navigating ambiguity
• Customer-focused mindset with a passion for developer experience

Bonus / nice-to-have

• Experience with browser or mobile instrumentation (RUM SDKs, telemetry collection).
• Mobile development experience (iOS or Android) or familiarity with mobile performance and telemetry.
• Contributions to OpenTelemetry or other observability OSS.
• Experience building developer-facing platforms or observability products.
• Familiarity with session replay, sampling strategies, or user behavior analytics systems.

Compensation range: $154,445 - $185,334 USD.