Sonio
Staff Engineer
2mo ago
EuropeLeadRemoteelixirphoenixsystem architecture
Staff Engineer responsible for architecting and leading backend development of Elixir/Phoenix systems in prenatal medicine AI.
Responsibilities
- As a Staff Engineer at Sonio, you will be the ultimate technical authority for our Elixir/Phoenix ecosystem. You will join one of our squads led by Romain (Engineering Manager), which houses the core of our backend codebase.
- In this role, you will architect high-scale, resilient systems and arbitrate complex technical decisions to ensure the platform remains performant as we grow. You act as a force multiplier, driving engineering velocity across your squad through strategic design, clear communication, and deep-tier problem-solving.
- Your main missions:
- Be the in-house Elixir / Phoenix expert squads rely on for the deepest problems
- Drive architecture for scale: concurrency, fault tolerance, clustering, back-pressure, recovery patterns
- Own the hardest problems end-to-end—from scoping and design to implementation—while distributing knowledge across the team.
- Author RFCs / ADRs for cross-squad changes and review others' designs
- Drive the refactors and tech-debt reductions that unlock velocity
- Grow the team through pairing, code reviews, design reviews and internal talks
- Contribute to senior / staff hiring (case design, tech deep-dives)
- You'll join a growing engineering team with real room to shape how we build.
Other
- Each year, 140M children are born. Birth defects affect 1 in 33 births in developed countries, and in 50% of cases, they are not detected during prenatal examinations. Prenatal medicine is particularly complex, and the scans impose heavy responsibilities on healthcare professionals. They can also be a source of stress for future parents.
- Resulting from 5 years of collaboration between world-renowned experts from Necker Hospital and Ecole Polytechnique, Sonio uses artificial intelligence to improve prenatal screening and diagnosis. Based on patented algorithms and a proprietary expert database, Sonio aims to become the reference tool to help practitioners improve screening, reduce diagnostic errors, and optimize pregnant women’s medical path.
- Sonio's mission is to improve women's and children's health by promoting access and quality of care through technological innovation, medical expertise, and collective intelligence.
- Sonio is a mission-driven company, so interest in our mission is critical. Other requirements are:
- 8+ years of software engineering, with 3+ years in Elixir in production at scale (real bottlenecks debugged)
- You have expertise in web & cloud native environment,
- Deep BEAM mastery: GenServers, Phoenix, Ecto / PostgreSQL performance
- Distributed systems in a cloud context: fault tolerance, clustering, consistency/availability trade-offs, back-pressure, and recovery
- Strong architecture and API design; comfortable with event-driven, data-intensive systems
- Written communication is strong enough to author RFCs / ADRs that others use as a reference
- Technical leadership without authority: drives consensus across squads, mentors peers
- Fluent English; French a plus
- Bonus: experience in a regulated environment (medical devices, fintech…), React / TypeScript familiarity
- Location : We have offices in Paris, but this position can work remotely (ability to come to Paris every 1–1.5 months)
- Salary : €85k – €100k + 10% bonus
- We move fast and aspire to be transparent over the process - our objective is that the process from the first chat to an offer is no longer than a month. We also aspire to give an answer to every application in a week - if you have not heard from us, please follow up at