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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Software Engineer - AI Agents & Developer Platform - **Company:** We're Fever - **Location:** Madrid, Spain - **Contract:** Permanent contract - **Skills:** Multitier Architecture, Artificial Intelligence, Continuous Integration, Relational Databases, Software Design Patterns, Open Source Technology, Software Engineering, Application Enhancement Tool, Large Language Models, Multi-Agent Systems, Backend, Build Tools, Restful APIs, Automation Anywhere - **Published:** August 24, 2026 - **Apply:** https://www.adzuna.es/contact-us.html ## About the Role + 5+ years building and operating production software at meaningful scale, with end-to-end ownership (not just shipping isolated features). + Strong software design fundamentals: testing, design patterns, clean architecture. + Backend depth: RESTful APIs, relational databases and SQL, distributed and event-driven patterns (queues, messaging) behind high-traffic services. + Full production ownership: CI/CD, observability, infrastructure. "Done" means healthy in production, not merged. + Proficient business English. Built on top, AI & agents + 1 to 2+ years shipping LLM applications to production (not just prototypes), with hands-on command of context engineering, RAG, multi-agent orchestration, and evals. + You've personally authored skills, sub-agents, evals, or verification harnesses, and can walk us through something real you built. + You think in measurements: baselines, before/after comparisons, and killing experiments that don't move the needle. Bonus points + Public work on agent harnesses, AI evaluation, or developer experience: open source, talks, blog posts, papers. + Experience building internal tools or developer platforms, where other engineers are your users. + Comfort operating with ambiguity at startup speed: small teams, no playbook, decisions you own. ## Description We're building the team that defines how AI transforms Product Engineering at Fever. This is a backend engineering role first: you need strong software fundamentals to build systems that scale and hold up in production. The AI expertise builds on top of that foundation. You won't just use agents, you'll build the harnesses, evals, and infrastructure that make them ship reliable, high-quality output across the entire company. You'll join the AI & DevEx team. Our mission is to raise the performance of Fever's whole Product Engineering organization, not just individual engineers, but entire squads (product, design, and engineering together) and everything that surrounds their work: CI/CD, observability, infrastructure, data, and how people communicate and coordinate. We look for the highest-leverage points in that chain and build AI-powered tools to improve them, always backed by measurement, not assumptions. What you'll work on + Agentic harness: Build the skills, sub-agents, guardrails, and verification systems that make agents produce high-quality, trustworthy output, for engineering and beyond. + Knowledge base: Build the shared knowledge substrate agents read from and write into, growing it from team-level to something that compounds across all of Fever. + Delivery substrate: Own the cloud dev environments, CI runtime, and autonomous-delivery rails that turn a request into an environment, an agent run, and a reviewable pull request. You're responsible for how fast and reliably this works. + AI across how squads work: Go beyond coding agents. Find where AI removes friction in planning, coordination, and communication across a squad's daily work. + Measurement: Build the evaluation and metrics systems (baselines, before/after comparisons, DORA metrics, lead time, real adoption) that ensure every change ships on signal, not vibes. + Inference economics: Optimize AI workflows for speed and cost: model routing, prompt caching, and choosing self-hosted vs. frontier models based on the quality/cost trade-off. + Engineering excellence: Testing, design patterns, CI/CD, and observability. Everything ships as production software, and you help set the bar for what good looks like. ## Related Videos - [Rest API Antipatterns](https://www.wearedevelopers.com/videos/100208-rest-api-antipatterns) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Modern Data Architectures need Software Engineering](https://www.wearedevelopers.com/videos/1030-modern-data-architectures-need-software-engineering) - [Agentic employees in world's most downloaded FinTech app](https://www.wearedevelopers.com/videos/100123-agentic-employees-in-world-s-most-downloaded-fintech-app) - [Nest.js - TypeScript in the backend can also be clean](https://www.wearedevelopers.com/videos/1033-nest-js-typescript-in-the-backend-can-also-be-clean) - [Building a Multi-Agent Orchestration Engine That Actually Follows the Rules](https://www.wearedevelopers.com/videos/100159-building-a-multi-agent-orchestration-engine-that-actually-follows-the-rules) ## Related Articles - [Navigating the AI Shift](https://www.wearedevelopers.com/magazine/629-navigating-the-ai-shift) - [Never delegate the understanding](https://www.wearedevelopers.com/magazine/749-never-delegate-the-understanding) - [Dev Digest 132 - Binging WADFlix?](https://www.wearedevelopers.com/magazine/473-dev-digest-132-binging-wadflix) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [What is Agentic Programming and Why Should Developers Care?](https://www.wearedevelopers.com/magazine/625-what-is-agentic-programming-and-why-should-developers-care)