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Fever

AI Staff Engineer

RemoteSpain only
Published
Role
Backend
Experience
Senior
Salary not disclosed
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Open to ES only. Set where you work from to check your eligibility.

No BS summary

Senior Software Engineer with 5+ years of production software experience and deep LLM application knowledge. Must have strong engineering fundamentals, backend depth (APIs, SQL, async patterns), and end-to-end production ownership. Experience building AI agents, skills, and evaluation harnesses is required. Focus on AI for Product Engineering, including agentic harnesses and delivery substrates.

Core skills

LLM applicationsAIagentic harness

Required skills

RESTful APIsSQLcontext engineeringRAGmulti-agent systemsorchestrationevals

Optional skills

agent harnessesAI evaluationdeveloper experienceAI-era engineering toolinginternal toolsdeveloper platforms

Required languages

English

What you'll do

  • Build and improve the skills, sub-agents, guardrails, tools, and verification that make agents produce high-quality output — not just for engineering, but for the entire squad and org.
  • Build the shared knowledge-base substrate these agents read from and write into — and grow it from team-level into something that compounds across the entire Fever organization.
  • Cloud dev environments, CI runtime, ephemeral environments on demand, and migration tooling — the road every engineer drives on — plus the rails that turn a request into an environment, an agent run, and a pull request with reviewable evidence.
  • Own how fast it is and how reliably it works.
  • Look beyond coding agents to the whole operating reality of a squad — assistants for engineering leads, the tooling and workflows people work through, the way they plan, coordinate, and communicate — and find where AI removes the most friction.
  • Build the measurement substrate that lets every change land on signal, not vibes.
  • Naked baselines, “ship only on a measured improvement,” and metrics that matter: lead time idea→production, DORA, real adoption.
  • Make AI-driven workflows fast and cost-bounded: model routing, prompt caching, and knowing when self-hosted open-source wins versus frontier models on the joint quality + cost frontier.
  • Work directly with the squads we serve so the tools actually get used — and actually make people better, measured, not assumed.
  • Testing, design patterns, CI/CD, observability.
  • Everything here ships as production software, so the people who build it set the bar for what good code looks like.

What they require

  • 5+ years building and operating production software at meaningful scale — you’ve owned systems end to end, not just shipped isolated features.
  • Strong software design fundamentals: good practices, testing, design patterns, clean architecture.
  • You don’t just get things done; you get them done right.
  • Backend depth: RESTful APIs (implementation and consumption), relational databases and SQL, and the distributed and async / event-driven patterns (queues, messaging) behind high-traffic services.
  • End-to-end production ownership: CI/CD, observability and monitoring, infrastructure, and accountability for how your code behaves once it’s live.
  • “Done” means healthy in production, not merged.
  • Proficient in business English.
  • At least the last 1–2 years deep in LLM applications shipped to production, not just prototyped — with a working command of the modern toolkit: context engineering, RAG, multi-agent systems and orchestration, and evals.
  • You build with agents, you don’t just use them.
  • You’ve authored skills, sub-agents, evals, and verification harnesses yourself — and you can show us something real you built with agents and walk us through how you did it.
  • You think in measurements: baselines, before/after comparisons, and killing experiments that don’t move the needle.
  • Comfort operating with ambiguity at startup speed — small teams, no playbook, decisions you can’t outsource.

Benefits

  • Attractive compensation package consisting of base salary and the potential to earn a significant bonus for top performance.
  • Stock options.
  • Opportunity to have a real impact in a high-growth global category leader
  • 40% discount on all Fever events and experiences
  • Home office friendly
  • Responsibility from day one and professional and personal growth
  • Great work environment with a young, international team of talented people to work with!
  • Health insurance and other benefits such as Flexible remuneration with a 100% tax exemption through Cobee.
  • English Lessons
  • We have free food, drink and fruit at the office!
  • Possibility to receive in advance part of your salary by Payflow.
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