Member of Technical Staff — CI Engineer

RadixArk • Palo Alto, CA

2h

About The Position

RadixArk is hiring a Member of Technical Staff — CI Engineer to own the infrastructure that keeps SGLang moving. Our CI system runs 300+ GPU tests across NVIDIA, AMD, Intel, and Ascend hardware pools, gating every commit to one of the fastest-growing open-source LLM inference engines. When CI is green and fast, 100+ contributors ship with confidence. When it isn't, the entire project stalls. That bottleneck is your problem to solve.
You won't just maintain pipelines — you'll architect them. You'll replace brittle static thresholds with regression-based detection, harden runners against supply-chain attacks from fork PRs, and cut cycle times so contributors get feedback in minutes, not hours. You'll work directly with core maintainers, hardware partners, and the open-source community to keep the system that gates every merge request trustworthy, fast, and secure.
This is not a role for someone who wants to write CI YAML and walk away. It's for an engineer who treats CI infrastructure the way we treat serving infrastructure — as a system worth designing well.

Requirements

• 3+ years operating CI/CD at scale (GitHub Actions, Buildkite, Jenkins, GitLab CI, or similar)
• Deep Linux, Docker, GPU computing knowledge
• Self-hosted runner management experience
• Strong Bash and Python
• Security mindset — CI supply chain risks, fork PR attack vectors, runner hardening
• NVIDIA GPU drivers, CUDA, NCCL, InfiniBand/RDMA experience in CI contexts
• Familiarity with ML inference workloads (model loading, KV cache, quantization)

Nice To Haves

• Large open-source project CI experience (100+ contributors)
• AMD ROCm or Intel XPU CI pipelines

Responsibilities

• Own CI reliability end-to-end — triage failures, distinguish real regressions from flaky tests and infra issues, keep main green
• Build regression-based CI — replace hardcoded static thresholds with automated baseline comparison (metrics pipeline, durable storage, detection logic)
• Harden runner infrastructure — ephemeral runners, container isolation, security hardening for fork PR execution
• Cut CI time — right-size eval suites, deduplicate server startups, separate PR smoke tests from nightly full runs
• Improve developer experience — faster feedback, clearer failure messages, workflow orchestration

Benefits

• We offer competitive base with meaningful equity, comprehensive health benefits, and flexible work arrangements.
• Compensation is determined by location, level, and experience.

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Education Level: No Education Listed