Fullstack Developer

Your mission

You'll be part of a small team of software developers building the factory of tomorrow. As our Full Stack Developer, you'll work across the entire product flow — from foot scanning and production to the consumer experience — refactoring existing software and building new tools and services. You'll tackle problems you've never encountered before, grow your knowledge every day, and directly shape the way we build.

What you'll do

• Build and refactor features end-to-end, across interfaces, production tooling, and consumer-facing apps

• Develop and integrate REST and GraphQL APIs — both sides of the contract

• Create responsive, polished frontends that translate design intent into production UI

• Work with Docker as part of normal development and deployment

• Make architectural and product decisions, not just implement them

• Collaborate closely with backend, frontend, design, and hardware teammates

• Continuously raise the quality bar: performance, testing, and code health on both sides of the stack

• Own product and platform flows end-to-end: design, build, ship, operate, and improve. Not "frontend with backend tickets," and not "backend with React on the side." Real ownership across both sides of the API

• Drive architectural decisions that span the stack: where logic lives, how data flows, how systems stay coherent as they grow

• Operate production systems. Debug across browser, API, queue, database, and infrastructure, and improve observability so the next person doesn't have to start from scratch

• Lead on performance and scalability on both sides: frontend render performance, bundle and asset strategy, backend query and queue performance, caching, async processing

• Apply real security awareness across the stack: authentication and authorization done correctly, common exploits avoided by design (injection, SSRF, broken access control, XSS, CSRF), and dependency hygiene

• Navigate the everyday tradeoff between shipping fast and building sustainable systems, and explain your reasoning to people who aren't engineers

• Collaborate directly with hardware engineers on production-side workflows, and with operations on scanning and consumer-facing flows

• Mentor other engineers and help establish the practices (reviews, testing, deployment, on-call) that scale with the team

Your profile

• Senior-level experience as a full-stack engineer who has genuinely owned both sides. Not a frontend dev with backend tickets, not a backend dev who occasionally touches React

• Strong React, TypeScript, and Next.js on the frontend; strong Node.js fundamentals

• Demonstrated architectural judgment across the stack: knowing where to put logic, when to introduce abstractions, when to extract a service

• Production operations experience: debugging real incidents end-to-end across browser, API, queue, database, and infrastructure

• Performance and scalability work on both sides, on systems with real load

• Security awareness beyond basic auth. You understand the common attack surface and design to avoid it

• Comfort with ambiguity and the ability to drive technical direction independently

Big advantage

• Laravel, Laravel Nova, and PHP — this is our primary backend stack, and full-stack here genuinely means full-stack

• Tailwind CSS

• Docker as part of normal development and deployment

• Solid relational database work (MySQL); exposure to non-relational stores (MongoDB, InfluxDB) is a plus

Background

We care about what you can do, not where you learned it. Formal CS background, apprenticeship, serious open-source contributions, or a strong portfolio of shipped work, all valid signals.

Why us?

At Zellerfeld, you will find a multidisciplinary team of engineers, SW and HW specialists, entrepreneurs, designers, and students with a common passion. We embrace contrarian thinking, humility, pushing limits, and improving ourselves. We utilize a flat hierarchy, and we want your voice to be heard. We also care about bonding because we want to be a tight-knit community, so be prepared to spend quality time with everyone, including the CEO!

As a company specializing in both hardware and software, we value close collaboration within our team. Therefore, we are seeking candidates who can join us at our office in Hamburg.