Senior Kotlin Engineer (m/f/d) - B2B Sales & Distribution team

Coursekingdom; Deutschland; On-site; EUR 90,000 - 140,000; Full time

Benefits offered by this job

Work from Anywhere

Hybrid work model

Wellbeing support

Learning & Development

Mentoring Program

Job summary

Flix is seeking a Senior Kotlin Backend Engineer to design and develop backend services in Kotlin and Spring Boot, powering partner-facing ecosystems. You will build REST APIs, contribute to architecture, and improve observability and performance in a distributed, AI-enabled environment.

Join a hybrid work model with opportunities for learning, mentoring, and career growth across global mobility solutions. Strong emphasis on clean code, cloud infrastructure, and modern dev practices.

Qualifications

• 5+ years of professional backend development experience with JVM languages and at least 2 years with Kotlin
• Hands-on experience with Spring Boot
• Experience building and maintaining REST APIs and distributed systems
• Solid SQL knowledge and relational database design (MySQL, PostgreSQL)
• Strong software engineering fundamentals, clean code, and ORM/persistence familiarity
• Collaborative, pragmatic, and comfortable in cross-functional Agile teams
• Preferred: AWS, Kubernetes, GitLab CI/CD, Kafka, Terraform, LLM integrations, RAG systems, AI product development, or legacy migration experience

Responsibilities

• Design and develop backend services in Kotlin and Spring Boot
• Build and maintain REST APIs used by internal and external partners
• Participate in architectural decisions and modernization initiatives
• Improve observability, performance, and reliability of backend systems using DataDog
• Contribute to CI/CD pipelines and cloud infrastructure on AWS and Kubernetes
• Work in an AI-native development environment with AI-integrated code review automation

Skills

Kotlin

Spring Boot

REST APIs

SQL / PostgreSQL

Distributed systems

CI/CD

AWS

Kubernetes

Agile

ORM / persistence

Tools

DataDog

Terraform

Kafka

GitLab CI/CD

Job description

At Flix, we offer a tech-driven environment where innovation meets real-world impact, with competitive pay, strong growth opportunities, and a culture of collaboration and ownership. B2B Sales & Distribution team in Demand Division builds and operates the backend platform powering Flix's partner-fac

Senior Kotlin Engineer (m/f/d) - B2B Sales & Distribution team

Description

At Flix, we offer a tech-driven environment where innovation meets real-world impact, with competitive pay, strong growth opportunities, and a culture of collaboration and ownership. B2B Sales & Distribution team in Demand Division builds and operates the backend platform powering Flix's partner-fac

At Flix, we offer a tech-driven environment where innovation meets real-world impact, with competitive pay, strong growth opportunities, and a culture of collaboration and ownership.

B2B Sales & Distribution team in Demand Divisionbuilds and operates the backend platform powering Flix's partner-facing ecosystem — including a self-management platform for partners, a back office portal for internal users, and an AI agentic bot supporting partner operations. As aSenior Kotlin Backend Engineer (m/f/d), you can make an impact by supporting a significant modernization of backend architecture and working in an AI-native development environment.

About the Role

• Design and develop backend services in Kotlin and Spring Boot
• Build and maintain REST APIs used by internal and external partners
• Participate in architectural decisions and technical modernization initiatives
• Improve observability, performance, and reliability of backend systems using DataDog
• Contribute to CI/CD pipelines and cloud infrastructure on AWS and Kubernetes
• Work in and contribute to an AI-native development environment — including AI-integrated code review automation and an internal Claude Code plugin marketplace covering engineering standards: Kotlin/Spring Boot conventions, architectural patterns, testing practices, database guidelines, and team-specific conventions.

About You

• 5+ years of professional backend development experience with JVM languages with a t least 2 years of commercial experience with Kotlin
• Hands-on experience with Spring Boot
• Experience building and maintaining REST APIs and distributed systems
• Solid SQL knowledge and relational database design, including MySQL and PostgreSQL
• Sound software engineering fundamentals, clean code practices, and familiarity with ORM and persistence layers
• Collaborative and pragmatic, comfortable working in cross-functional Agile teams
• Preferred: AWS, Kubernetes, GitLab CI/CD, Kafka, Terraform, LLM integrations, RAG systems, AI product development, or legacy system migration experience

We recognize that everyone carries a unique set of valuable skills and experiences. If you think you could have an impact even though you don't meet 100% of the requirements, we still encourage you to apply. We want to hear from you!

What We Offer

• Work from (M)Anywhere: Depending on your role, work from another location for up to 60 days per year.
• Hybrid work model: We are an office-first company, but we offer flexibility to balance work and life.
• Wellbeing support: Access confidential 1:1 counselling, courses, and stress management for yourself and up to four family members.
• Learning & Development: Take advantage of language classes, training courses, and expert-led sessions to grow your skills.
• Mentoring Program: Connect with experienced colleagues to gain insights and accelerate your career.

At Flix, we empower our teams to push boundaries and shape the future of mobility. As we continue to scale globally, we harness cutting-edge technology to make mobility smarter, more sustainable, and more affordable.

If you're looking for a place where you can drive change and redefine how millions of people travel, Flix is the place where you can lead your journey!