Senior/Staff AI Infrastructure Engineer

Build the secure execution substrate for Echelon's agents. You will scale ephemeral sandboxes, optimize filesystem and startup performance, and make long-running agent work durable under load without weakening tenant isolation or operational control. What you'll own • Design and operate sandbox lifecycle systems for agent code execution, browser work, document processing, and tool use. • Improve sandbox startup time, density, scheduling, warm pools, caching, and resource utilization. • Build fast, reliable filesystem primitives for ephemeral and persistent agent state, large artifacts, and concurrent workloads. • Enforce tenant isolation, network policy, secrets boundaries, quotas, and least-privilege access. • Make long-running agent jobs durable through checkpointing, retries, idempotency, cancellation, and recovery. • Scale orchestration and control-plane services through rapid workload growth and unpredictable bursts. • Build observability for resource pressure, execution failures, queue health, noisy neighbors, cost, and end-to-end latency. • Run load tests, capacity plans, failure drills, and incident reviews; fix root causes rather than adding fragile workarounds. What you bring • 5+ years building production infrastructure, distributed systems, developer platforms, or execution runtimes. • Hands-on ownership of containerized or virtualized workloads in a multi-tenant production environment. • Strong Linux systems knowledge across processes, filesystems, networking, resource isolation, and performance debugging. • Experience with Kubernetes or a comparable scheduler, infrastructure as code, and cloud primitives on AWS or Azure. • Strong programming ability in Go, Rust, TypeScript, Python, or another systems-oriented language. • Experience designing for retries, idempotency, backpressure, load shedding, observability, and safe rollouts. • Security instincts appropriate for executing untrusted or model-generated work. Useful experience • Firecracker, gVisor, Kata Containers, namespaces/cgroups, seccomp, or eBPF. • Sandbox products such as E2B, Modal, Fly Machines, or custom ephemeral compute platforms. • FUSE, overlay filesystems, content-addressed storage, snapshotting, distributed caches, or object storage. • Agent runtimes, code interpreters, browser automation, remote development environments, or CI execution systems. • BYOC, private networking, customer-managed deployments, or enterprise security reviews. • Inngest, Temporal, Kafka, NATS, or other durable workflow and event systems. Benefits • Team lunches and dinners in the office. • On-site Gym access for all employees. • Fully covered health, dental, and vision insurance. • 401(k) plan. • Access to AI Tooling of your choice. • Unlimited PTO.