Devops Engineer

Job title: Devops Engineer

Location: London; full in-office working as default

Start date: ASAP

Reports to: CTO

Compensation: £60 - 90k + Equity

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Cosine at a glance

At Cosine, we’re building autonomous AI engineers that plan, write, and ship code inside real development workflows.

Cosine is designed for on-premise and virtual private cloud (VPC) deployments, including fully air-gapped environments. We build our agent tooling entirely in-house and post-train open-source models to deliver reliable, enterprise-grade coding performance in security-critical settings.

In 2024, Cosine achieved a 72% score on OpenAI’s SWE-Lancer benchmark, placing us among the strongest real-world software-engineering AI systems evaluated.

YC-backed and well-funded, Cosine was founded by experienced operators focused on building dependable, production-grade AI.

This role is based in our Hoxton office, five days a week, because close collaboration, fast feedback, and shared context matter for the problems we’re solving.

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The role

We’re looking for a Devops / Senior Platform / Infra Engineer to own the core infrastructure that powers Cosine’s products — from Kubernetes and deployment pipelines to networking and platform services.

You’ll design and run the “paved road” that our engineers, researchers, and customers build on: reliable Kubernetes clusters, fast and safe CI/CD, solid observability, and hardened environments for demanding enterprise and on-prem deployments. You’ll also wear a classic “DevOps/SRE” hat: thinking in SLOs, running incident response, and keeping us up even as we move quickly.

This is a high-ownership role at a fast-paced, venture-backed Silicon Valley startup. You’ll work directly with founding engineers and leadership, and your decisions will materially shape how we build and ship products.

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What You’ll Do

• Own core infrastructure
• Design, operate, and evolve our Kubernetes-based platform (EKS or similar), including cluster topology, node groups, autoscaling, and multi-environment isolation.

Help design patterns for secure enterprise and on-prem / regulated deployments.

Partner with product & research

• Work closely with application, ML, and research teams to understand their needs and translate them into reusable infra building blocks.
• Provide guidance on “how to run this in production” — capacity planning, failure modes, and operational readiness reviews.
  

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What We’re Looking For

• Have strong experience
• 5+ years building and operating production infrastructure on a major cloud (AWS, GCP, or Azure).
• Significant hands-on experience running Kubernetes in production (EKS/GKE/AKS or self-managed):
• Cluster upgrades, autoscaling, node group design, and multi-env setups.
• Helm or similar for packaging services.
• Think in infrastructure-as-code
• Deep experience with IaC tools (Pulumi, Terraform, CDK, or similar).
• Comfortable managing infra changes via code review, CI, and automated rollouts.
• Care deeply about reliability
• Have owned the uptime and performance of user-facing systems.

Argo CD or other GitOps tools for Kubernetes.

On-prem, air-gapped, or regulated industry deployments (e.g. finance, healthcare).

AI/ML infrastructure (GPU workloads, model hosting, feature stores).

Prior experience as an early infra / platform hire at a startup.

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Cosine is an equal opportunity employer.

We value diverse backgrounds, perspectives, and ways of thinking, and we’re committed to creating an inclusive and respectful workplace.

We encourage applications from anyone who meets the role requirements, even if you don’t meet every single qualification. If you need reasonable adjustments at any stage of the hiring process, we’re happy to discuss them.

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Compensation, Benefits & Ways Of Working

We’re an in-office team, five days a week, by design. We believe the work we’re doing benefits from being together, collaborating closely, and building shared context.

What You Can Expect

• Competitive salary, benchmarked to the market

Equity / share options, so you share in the upside you help create

30 days’ holiday + bank holidays

Genuine 9–5 working hours — we don’t expect late nights or weekend work

Work hard in the office, collaborate closely, and switch off properly

Dog-friendly office — bring your dog to work

Daily lunch provided

Monthly team breakfasts

Monthly socials

Pension

High-quality equipment to do your best work

We care about focus, sustainability, and doing great work — not performative overwork. We value people who show up, contribute thoughtfully, collaborate well with their colleagues, and then go home.

This role won’t suit everyone. But if you want structure, clarity, strong collaboration, and a team that takes both the work and work-life balance seriously, it’s a great place to be.

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Agency & Data Protection Notice

To comply with UK GDPR and our internal data-protection and equal-opportunity obligations, we only accept candidate applications and agency submissions via our Applicant Tracking System (ATS). This ensures appropriate privacy notices, lawful processing, auditability, and consistent retention controls.

Any CVs or candidate details received outside the ATS (including via email, Slack, or direct message) will be treated as unsolicited, will not be co

nsidered as part of the recruitment process, and will not give rise to any fee or payment obligation.