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. Pay: Target pay ranges based on Geographic Zones* for Level 4: Zone 1: San Francisco/Bay Area or NYC Metropolitan Area, Boston, Seattle - $191,800 - 263,670** Zone 2: Irvine, LA, Monterey, Santa Barbara, Santa Rosa, Austin, Portland, Philadelphia, Chicago - $172,600 - $237,270** Zone 3: All other US locations - $163,000 - $224,070** LaunchDarkly operates from a place of high trust and transparency; we are happy to state the pay range for our open roles to best align with your needs. Exact compensation may vary based on skills, experience, and location. *Within the United States, our geographic pay zones are defined by counties surrounding major metropolitan areas.**Restricted Stock Units (RSUs), health, vision, and dental insurance, and mental health benefits in addition to salary. About LaunchDarkly: Modern software delivery was supposed to be the foundation for a thriving digital business but reality has proven otherwise. Slow, inefficient development cycles, costly outages, and fragmented customer experiences are preventing developers from building their best software. The LaunchDarkly platform helps developers innovate on new features faster while protecting them with a safety valve to instantly rewind when things go wrong. Developers can target product experiences to any customer segment and maximize the business impact of every feature. And by gradually rolling out new application components, they escape nightmare "big-bang" technology migrations. The LaunchDarkly platform was built to guide engineers to the next frontier of DevOps by: Improving the velocity and stability of software releases, without the fear of end customer outages Delivering targeted experiences by easily personalizing features to customer cohorts Maximizing the business impact of every feature through the ability to experiment and optimize Coordinating the release and optimization of software to provide consistent experiences across mobile platforms and device types Improving the effectiveness and productivity of engineering teams, by providing insights into engineering cadence and stability At LaunchDarkly, we believe in the power of teams. We're building a team that is humble, open, collaborative, respectful and kind. We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, gender identity, sexual orientation, age, marital status, veteran status, or disability status. LD invites any applicant to review our written Affirmative Action Plan. To do so, contact People Ops at hr@launchdarkly.com. Do you need a disability accommodation? Fill out this accommodations request form and someone from our People Operations team will contact you for assistance. Your safety matters to us. To protect yourself from potential scams, LaunchDarkly recruiters will only contact you from @launchdarkly.com email addresses or via LinkedIn from "Verified Recruiter" accounts. Be cautious of emails from other domains. Legitimate LaunchDarkly recruiters will never ask for money, fees, or banking information before making a job offer. LaunchDarkly will never make a job offer without conducting a formal interview process. Our interview process does not involve asking detailed questions by email. If you are ever unsure about a communication that you receive, don't click any links—visit Careers | LaunchDarkly directly for confirmed job openings and links to apply.Please notify us of any fraudulent representation by sending an email to careers@launchdarkly.com.