Founding Principal Engineer (m/f/d)

Contract type
Ongoing
Work mode
Hybrid · Berlin, Germany
Experience
Lead / principal · Not stated

Level inferred from job title

Job description

Founding engineer role at a Berlin medical software startup, owning the entire platform (backend, data, infrastructure, security and identity) behind a smartphone-based microscope cell-analysis product. The focus is making the system trustworthy and reliable enough for clinical use.

At a glance

Employment
Full-time · Employee (employment agreement)
Work mode
Hybrid · Berlin, Germany
Languages
English

What you'll do

  • Own the platform end to end: backend, data, infrastructure and security.
  • Get it ready for clinical use, and keep it reliable as we grow.
  • Build identity, access and data handling that clinics and auditors can trust.
  • Make the architecture calls: what to build now, what to defer, what to cut.
  • Set the engineering standard and help hire the team that follows.

What we're looking for

  • Platforms you've built and run: built backend platforms from scratch and run them in production, through outages, data incidents, migrations and growth.
  • Database depth: indexing, locking, transactions, replication, zero-downtime schema changes, and backups you've actually restored.
  • Security by default: authentication and authorisation, tenant isolation, secrets, audit logging.
  • Identity done properly: identity providers, sessions and tokens, roles and permissions, onboarding and offboarding.
  • Infrastructure: infrastructure as code, containers, Linux, networking and cloud.
  • Beyond the backend: able to read and change the app when the product needs it.
  • Systematic troubleshooting: reproduce first and fix root causes, working from logs, traces, metrics and query plans.
  • AI-native engineering: coding agents are part of your daily work.
  • Ownership: help shape the roadmap, push back on weak ideas, set your own priorities and raise problems early.
  • Range: worked across several companies, stacks or environments.

Nice to have

  • Regulated environments with audits: medical devices, health, finance.
  • Serving ML models in production.

Benefits

  • Ownership from day one: part of the company through our virtual share option plan (VSOP) as a founding engineer.
  • You grow with us: as the company grows, your role grows with it.
  • Real influence: you decide how we build software, and you shape the engineering team we build.
  • A competitive salary.
  • A product that matters: a medical device for real clinics, built together with clinicians and lab staff.
  • Flexible hours and office days.
  • English is our working language. German isn't required.
  • We sponsor the EU Blue Card if you're moving to Berlin.

Apply

Direct apply at Ferto Health GmbH

Opens the job posting at Ferto Health GmbH

About Ferto Health GmbH

Most labs still count cells under a microscope by hand. It's slow, repetitive, and error-prone. We're replacing that manual work with software. By combining a standard microscope with a smartphone, we run computer vision models that locate, track, and measure cells automatically in real time. We're starting with semen analysis and expanding to other routine microscopic samples.

Mission

Make automated, reliable diagnostic analysis accessible on any phone connected to a microscope.

Key facts

  • 2026
  • Berlin
  • Small, well-funded team in Berlin
  • Founded in 2026
  • Starting with semen analysis and expanding to other routine microscopic samples