Full stack engineer

About The RoleRadixArk is building the infrastructure layer for frontier AI systems - unified inference, training, and evaluation stacks powering next-generation LLM applications at scale. Our platform integrates high-performance model serving, RL pipelines, and large-scale distributed systems across GPUs, TPUs, and emerging accelerators. We work at the intersection of systems engineering, AI research, and developer experience. We are looking for a world-class Full Stack Engineer who thrives in high-ambiguity environments and wants to build foundational tools for the next decade of AI.RequirementsTechnical Excellence4+ years of professional full stack engineering experienceBased in Palo Alto, CA (Hybrid) / Remote (U.S.)Deep experience in:Frontend: React / Next.js / TypeScriptBackend: Python (FastAPI / Django) or Node.jsRESTful and/or gRPC API designStrong understanding of distributed systems conceptsExperience building systems that handle real-time streaming or high-throughput workloadsStrong database design skills (Postgres, Redis, etc.)Familiarity with containerized environments (Docker, Kubernetes)Strong software engineering fundamentals: testing, CI/CD, version control, design reviewsBonus (High Impact)Experience building developer tools or infrastructure platformsExperience in ML infrastructure, model serving, or AI toolingFamiliarity with observability stacks (Prometheus, Grafana, OpenTelemetry)Experience with WebSockets or streaming architecturesPerformance optimization at scaleExperience building internal platforms used by engineersResponsibilitiesYou will own end-to-end product surfaces across our developer platform:Design and implement high-performance web applications for AI infrastructure toolingBuild scalable backend systems that interact with distributed inference and training servicesArchitect APIs and service layers that serve enterprise and research customersDevelop observability dashboards, experiment tracking UIs, and performance analytics toolsOptimize real-time streaming interfaces for model inference workflowsWork closely with ML engineers and infra teams to expose complex systems through intuitive product surfacesLead architectural decisions for frontend-backend communication, state management, and performance tuningShip production-grade features in fast iteration cyclesYou will not just "write UI."You will build the control plane for frontier AI systems.Your work will directly power:Large-scale LLM inference systemsReinforcement learning training platformsEvaluation and experimentation frameworksDeveloper-facing AI infrastructure productsThis is not CRUD dashboard engineering.This is building the operating system for AI builders.About RadixArkRadixArk is building the infrastructure layer for frontier AI systems - unified inference, training, and evaluation stacks powering next-generation LLM applications at scale.Our platform integrates high-performance model serving, RL pipelines, and large-scale distributed systems across GPUs, TPUs, and emerging accelerators. We work at the intersection of systems engineering, AI research, and developer experience.CompensationCompetitive base salaryMeaningful equity ownershipFull benefitsAccess to top-tier AI tooling (enterprise Claude, Codex, etc.)Work alongside world-class AI systems engineersEqual OpportunityCompetitive salary and equity package.Work with a world-class team from xAI, Google, and leading research labs.Directly impact the future of open AI infrastructure.The most compelling perk in Silicon Valley isn't 401(k) matching.It's working on systems that define the next computing paradigm.If you want to build the infrastructure layer behind frontier AI - and ship fast - we want to talk.

Created: 2026-04-02