Senior Fullstack Engineer

At voize, we believe the greatest gift to frontline workers is time—time to care, connect, and be present. Today, that time is lost to busywork and complex systems that pull them away from what matters most: people.

Our vision is to change that by building AI companions that seamlessly take over digital workflows. We don’t replace humans with technology—we amplify their impact.

Our mission is backed with a $50M Series A funding led by Balderton Capital, with support from HV Capital, Y Combinator, and other leading VCs. Today, 2,000+ facilities trust voize, and over 200,000 users rely on our AI companion to ease their daily workload.

Your Mission

As a Senior Fullstack Engineer at voize, you will be a co-owner of voize's ML App—the in-house platform for annotation, data exploration, ML training orchestration, model evaluation, and the HIPAA-bearing data flows that move PHI from customer to model. Make in-house tooling good enough that revisiting Labelbox/Encord-style vendors is permanently off the table, and unblock HIPAA-compliant training on US customer data.

Your Daily Business - No two days are alike

• Co-own the ML App codebase (React/TypeScript SPA + Kotlin services + Kotlin ETL on EKS)

• Design and ship features for data labelling, data exploration, ML training orchestration, model evaluation, model playgrounds, and ML-issue triage

• Drive the next iteration of in-house annotation tooling—UX, throughput, task-type extensibility—to the bar where vendor revisits are unnecessary

• Maintain CI/CD, EKS deploys, and LGTM-stack observability for ML App; triage and fix defects

• Pair with the Platform team on platform-side prerequisites (FGA proxy, OIDC) that the new training flows depend on

Your Skillset - What you bring to the table

• 5+ years building production fullstack web apps with React + TypeScript

• Excellent Kotlin (or JVM) backend experience—services, ETL/data pipelines, schema design

• Demonstrated ownership of a complex, production-critical system

• Comfortable engineering with regulated / sensitive data (HIPAA, GDPR, BAA, PHI, or similar)

• Strong product/UX instincts (annotation, labeling, data exploration, ops UI)

Growing together - what you can expect at voize

• We are a fast-growing startup, meaning you will tackle challenges, grow quickly, and make a real impact, giving frontline workers more time for people.

• We foster an open, collaborative culture with regular team events, whether you work from our Berlin office or remotely across Germany.

• Become a co-creator of our success with stock options.

• Generous perks: 30 vacation days plus your birthday off, Germany Transport Ticket, Urban Sports Club, regular company off-sites, and access to learning platforms such as Blinkist and Audible, plus free language courses.

• You decide when you work best, meaning flexible working hours and a good hybrid setup.