(Senior) Backend Engineer – Golang arbeitnow 7NXT GmbH Berlin · 10/16/2026

Primetime; Berlin; Hybrid; EUR 90,000 - 130,000; Full time

Benefits offered by this job

30 days vacation

Hybrid work model

Work from home

Mobility budget

Wellbeing programs

Office fruits & snacks

Pet-friendly office

Job summary

Gymondo, a leading digital fitness platform in the DACH region, is hiring a (Senior) Backend Engineer in Berlin. You will build scalable backend services with Golang and Gin-Gonic, design REST APIs per OpenAPI, and contribute to a microservices-based architecture. Join a team that values code quality, testing, and agile delivery.

Expect a hybrid Berlin model with office days and remote work. You will shape the technical foundation, modernize legacy systems, and drive data-driven features across

Qualifications

• 4+ years of backend-focused development, including infrastructure.
• 3+ years contributing to microservice architectures focusing on reliability, scaling, stateless apps, event-driven systems and clean architecture.
• 3+ years designing REST APIs following OpenAPI standards.
• Proven hands-on experience with Golang and Gin-Gonic.
• Ability to design proof of concepts and prototypes.
• Standardised coding practices: peer reviews, unit testing and agile development.
• Open mindset and interest in state-of-the-art technologies.

Responsibilities

• Build, improve and maintain scalable backend services using Golang and Gin-Gonic.
• Design and implement REST APIs following OpenAPI standards for clarity and maintainability.
• Contribute to our microservice architecture focusing on reliability, scaling and statelessness.
• Translate legacy concepts into maintainable, modern patterns.
• Develop data-driven features across the full development lifecycle.
• Work on scalable infrastructure using AWS, Kubernetes and Terraform.
• Participate in peer code reviews, write unit tests and promote agile practices.
• Share knowledge and grow together with the team.

Skills

Golang

Gin-Gonic

REST APIs

OpenAPI

Microservices

Clean architecture

Unit tests

Agile

Code reviews

Cloud/AWS

Tools

Docker

Kubernetes

Terraform

Job description

Location: Berlin — hybrid, 3 days in the office

Salary band: Shared before your first interview

Your impact

As (Senior) Backend Engineer at Gymondo, you build and improve the scalable backend systems that power our platform for hundreds of thousands of active users. You work with a modern tech stack, establish new services using clean architecture principles, and help translate legacy concepts into maintainable, future-proof code. Your work directly shapes the technical foundation that enables Gymondo to grow — reliably, efficiently and at scale.

What you’ll drive

You build, improve and maintain scalable backend services using Golang and Gin-Gonic, following clean architecture and established design patterns

You design and implement REST APIs following OpenAPI standards, with a focus on clarity, reliability and long-term maintainability

You contribute to our microservice architecture — working on reliability, scaling, stateless applications and event-driven systems

You rebuild legacy concepts and translate them into well-known programming patterns with transparent and maintainable business logic

You develop data-driven features and are involved in all stages of the development process — from design to deployment

You work on our scalable, automated infrastructure using AWS, Kubernetes and Terraform

You participate in peer code reviews, write unit tests and champion agile development practices

You share knowledge, discuss better solutions openly and grow together with the team

What defines you

Must-have

4+ years of professional experience in backend-focused development, including infrastructure

3+ years contributing to microservice architectures with a focus on reliability, scaling, stateless applications, event-driven systems and clean architecture

3+ years designing REST APIs following OpenAPI standards

Proven hands-on experience with Golang and Gin-Gonic

Ability to design proof of concepts and prototypes

Standardised coding practices: peer code reviews, unit testing and a preference for agile development

An open mindset and genuine interest in state-of-the-art technologies and methodologies

Nice-to-have

Experience with JVM languages (Kotlin / Java) and frameworks such as Ktor, Spring or Node.js

A Product Engineer mindset: balancing technical excellence with business impact, proactively identifying trade-offs that prioritise user value and speed-to-market without compromising long-term system health

Strong communication skills across the Product & Engineering team and additional stakeholders

A collaborative, humble approach — you promote good relationships in your guild and are always willing to learn from others

Success requires positive energy. That's why we ensure the right conditions are in place — physically, mentally, and within the team:

30 days of vacation per year + Christmas Eve & New Year's Eve as additional paid days off

Hybrid working model — 60% in the office, 40% from home, applicable to all working hours

Up to 4 weeks of work from abroad per year (Berlin-based roles)

Free Urban Sports Club M membership & access to Nilo Health for mental health and personal development

Free access to 7Mind, Gymondo & Buddyfit — our own digital wellbeing products

€30 monthly mobility budget via Navit

€1,000 annual training budget + a wide range of opportunities for personal growth and development

Family-friendly benefits — childcare costs & paid sick days for children

The office classics — fruit & vegetable basket, muesli & yogurt (also vegan), drinks & snacks

Pet-friendly office — four-legged colleagues are very welcome!

These benefits apply to full-time and part-time permanent employees. Working students and interns receive a pro-rated selection.

People who make things happen

Gymondo is one of the leading digital fitness and nutrition platforms in the DACH region — with over 2,000 workouts, holistic training programmes and smart nutrition plans. As part of 7NXT Health Group, we help millions of people make movement a lasting part of their everyday lives.

Our team pushes each other, thinks critically and grows together. We take responsibility — for our users, our products and our planet.

We welcome what makes you unique.

At Gymondo we believe in diversity, openness and team spirit. No matter which gender you identify with, whether you have a disability, what your neurotype is, where you come from, what you believe in or how you love — you are welcome here.

Don’t meet all the criteria? No problem — if you’d like to help shape the future of fitness & wellbeing with us, we look forward to your application.

Need a more accessible process or have questions? Write to us — we’ll find a way.

This overview was written from the original listing to help you understand the role. Always confirm the specifics on the employer’s application page.