Senior software engineer

About usAt Milu Health, our mission is to make healthcare affordable for millions of Americans. We receive real-time electronic health record data from consented patients, and we run that clinical data through a series of LLM agents to find ways we can proactively help patients get better quality and better value healthcare. When our agents find opportunities, our team of providers review every flagged intervention and SMS patients.We’re an early-stage startup backed by a16z, already working with thousands of patients, growing 10x every 6 months — and we’re just getting started.How we think about AI Engineering at MiluEvery technological wave has changed how software gets built. AI engineering is different : we’re not just building apps that people click on. We’re building autonomous agents that reason, plan, and take action.At Milu, this means engineering AI-native systems that analyze medical data, orchestrate decisions, and surface savings automatically. Our engineering philosophy centers on multi-agent collaboration, real-time reasoning, and production-grade AI systems that deliver results.Your role and purposeAs a Senior Software Engineer at Milu Health, you’ll be a founding member of our Madrid hub and help us scale our AI ecosystem. You’ll design and ship production-grade systems where LLM agents collaborate, connect to real-world data, and help people save on healthcare.This is a role for someone who wants impact, ownership, and the thrill of building at the frontier of AI + healthcare.What you’ll doBuild and scale backend services with Type Script / Node.js, AWS, and Postgres.Expand our ecosystem of AI agents : multi-agent orchestration, planning, reasoning, and intelligent tool-calling.Design secure, scalable data pipelines for sensitive healthcare data (HIPAA, GDPR).Collaborate with product and design to ship full-stack features (Node.js + React).Ensure reliability, observability, and speed in systems that run at scale.Contribute to our engineering culture : small team, big impact, ownership-driven.What we’re looking forStrong experience with Type Script, Node.js, React.Background in cloud architectures (AWS) and relational databases (Postgres).Experience in fast-paced startup environments with small, high-performing teams.Great communication in English (our working language).Nice to have : Experience with AI agents, LLM frameworks, or applied ML systems.Background in healthcareWhat we offerHighly competitive salary package (70k€ / year)Health insurance planHybrid setup : 1 day / week in Madrid office, rest remote.Work alongside a world-class team backed by a16z.Ownership opportunities : join early, shape foundations.The chance to change how millions of people access healthcare.What happens after you apply?Our Talent Acquisition team is invested in creating the best candidate experience possible, so don’t worry, you will definitely hear from us. We will review your CV and keep you posted by email at every step of the process!