Sr Backend Engineer, Flag Delivery

About the Job

Software powers the world, and LaunchDarkly empowers teams to deliver and control it safely. As a Senior Software Engineer on the Flag Delivery team, you will own the critical-path systems that stream feature-flag configuration to every connected SDK globally, in near real time. These systems run at high scale and have to stay reliable, low-latency, and correct; when they fail, customers lose control of their features.

This is added headcount on a growing team. You will work on the next generation of the flag-delivery architecture, streaming rollouts, and reliability and scale hardening. Our stack is Go, AWS, Terraform, and Datadog, but exact tool match matters less than deep backend expertise and a track record of owning production systems.

Responsibilities

• Design, build, and operate the distributed systems that deliver feature-flag configuration to LaunchDarkly SDKs.
• Own and improve the reliability, latency, and scalability of our streaming and polling infrastructure.
• Debug and resolve complex production issues, sharing the team’s on-call rotation.
• Partner with SDK, Core Product, and Data Platform teams on how flags reach customers.
• Write maintainable, well-tested code and engage in code reviews, design reviews, and production-readiness discussions.
• Drive architectural decisions, trading off performance, cost, and operability.
• Raise the bar on observability, deployment safety, and operational process for Flag Delivery.

Qualifications

• 6+ years of professional backend engineering, with significant work on distributed or high-throughput production systems.
• Track record designing, building, operating, and debugging reliable, low-latency services.
• Strong production ownership, including on-call experience and a focus on reliability and observability.
• Proficient in at least one backend language (Go, Rust, Python) and comfortable on a cloud platform (AWS or equivalent).
• Hands-on with infrastructure-as-code (Terraform or equivalent) and observability tooling (Datadog, Prometheus, New Relic).
• Deep grasp of distributed-systems fundamentals: concurrency, partitioning, retries, idempotency, backpressure, and failure handling.
• Writes clean, maintainable code and collaborates well on technical design.
• Communicates clearly and holds a high bar for operational excellence.