Senior Software Developer (m/f/d) - Keycloak Identity & Access Management

CTS EVENTIM AG & Co. KGaA; Bremen; On-site; EUR 90,000 - 130,000; Full time

Benefits offered by this job

30 days vacation

25 days workation in EU

Flexible working hours

Sofa Concerts & events

Ticket discounts

Corporate benefits

Job Ticket / Germany Ticket subsidy

Bike leasing

Mental health program

GoFluent language platform

Lunch & Learn sessions

Job summary

CTS EVENTIM AG & Co. KGaA is seeking a Senior Software Developer to advance our Identity & Access Management and API Management platforms built on Keycloak.

You will develop extensions, integrate with APIs, and ensure secure authentication across international markets from our offices in Hamburg, Bremen, or Berlin. You will work on designing scalable authentication, authorization, and API security solutions while collaborating with product teams and stakeholders worldwide.

Qualifications

• Several years of Java software development in large-scale production systems.
• Experience with Identity & Access Management (IAM) and security challenges of modern authentication.
• Hands-on Keycloak experience, including customization and extension.
• Strong understanding of OpenID Connect and OAuth 2.0.
• Experience with API Management and API Gateways.
• Operating distributed applications in clustered or cloud environments.
• Interest in Application Security and Identity Security.
• Ability to explain complex concepts clearly and collaborate across teams.
• Very good German and good English language skills.

Responsibilities

• Identity & Access Management: Develop and operate our central IAM platform based on Keycloak, with your team.
• Keycloak Development: Build extensions and integrations for Keycloak across markets.
• Authentication & Authorization: Design secure solutions using OpenID Connect, OAuth 2.0, SSO, and Identity Federation.
• API Management: Develop API Gateway and integrate with identity platform, focusing on security and access control.
• Platform Reliability: Ensure stability, scalability, security, and observability of the identity platform.
• Troubleshooting: Analyze issues and contribute to sustainable solutions for incidents and performance.
• Stakeholder Collaboration: Work with internal customers, product teams and international EVENTIM entities.
• Technical Architecture: Contribute to architecture decisions and technical reviews.
• Knowledge Sharing: Support developers through code reviews and guidance.

Skills

Java development

IAM

Keycloak

OpenID Connect

OAuth 2.0

API Management

Distributed systems

Application security

German & English

Tools

Kubernetes

Terraform

OpenResty

Kong

NGINX

Apache APISIX

Job description

Our Auth API & API Management team develops and operates central platform services that support EVENTIM’s products across international markets.

A key part of our work is our central Identity & Access Management platform built on Keycloak. It enables secure authentication and Single Sign-On across different products and markets, operating internationally and handling high traffic volumes.

Closely connected to our identity platform are our API Gateway and API Management solutions , which ensure that APIs are exposed securely and reliably. Both areas are tightly integrated, particularly when it comes to authentication, authorization, and API security.

As a Senior Software Developer, you will work alongside your team to continuously develop and enhance these platforms, shaping essential solutions around Identity & Access Management, Authentication, and Security.

You can work from one of our offices in Hamburg, Bremen, or Berlin. We look forward to receiving your application!

Key Responsibilities:

• Identity & Access Management: Develop, configure, and operate our central Identity & Access Management platform based on Keycloak , together with your team.
• Keycloak Development: Build extensions and integrations for Keycloak, adapting the platform to the requirements of our products and international markets.
• Authentication & Authorization: Design secure and scalable solutions using OpenID Connect, OAuth 2.0, Single Sign-On, and Identity Federation.
• API Management: Further develop our API Gateway and API Management solutions and integrate them with our identity platform, particularly regarding API security, token validation, and access control.
• Platform Reliability: Take ownership of the stability, scalability, security, and observability of our identity platform in production.
• Troubleshooting: Analyze technical issues and contribute to sustainable solutions for incidents and performance challenges.
• Stakeholder Collaboration: Work directly with internal customers, product teams, and international EVENTIM entities to understand requirements and develop suitable technical solutions.
• Technical Architecture: Actively contribute your expertise to architecture decisions, technical concepts, and reviews.
• Knowledge Sharing: Support fellow developers through knowledge sharing, code reviews, and technical guidance.

What you’ll need :

• Several years of solid experience in Java software development , including working with large-scale, business-critical production systems.
• Practical experience with Identity & Access Management (IAM) and a strong understanding of the technical and security challenges of modern authentication systems.
• Ideally, extensive hands-on experience with Keycloak , including its architecture, configuration, and particularly its customization and extension capabilities.
• A solid understanding of OpenID Connect and OAuth 2.0 , including the underlying authentication flows, tokens, and security concepts.
• Experience with API Management and API Gateways , including their integration with modern authentication and authorization solutions.
• Hands-on experience operating distributed applications in clustered or cloud environments, with a strong interest in scalability, performance, and observability.
• A strong interest in Application Security and Identity Security , with a security-first mindset throughout design and implementation.
• The ability to explain complex technical concepts clearly and collaborate effectively with developers, architects, product teams, and international stakeholders.
• Very good German and good English language skills complete your profile.

Nice to have:

• Experience with Keycloak customization, SPIs, and extensions
• Experience with Quarkus
• Hands-on experience with API Gateway technologies , ideally OpenResty-based solutions such as Kong or Apache APISIX
• Knowledge of NGINX, OpenResty, or Lua for configuring and extending API Gateways
• Experience with Kubernetes and container technologies
• Experience with Terraform/Terragrunt and Infrastructure as Code (IaC)
• Experience with monitoring and observability tools , such as Grafana Cloud
• Experience with automated integration and end-to-end testing
• Experience with cloud platforms such as AWS, Google Cloud, or Azure
• Familiarity with agile software development methodologies

Benefits

• 30 days of paid vacation plus the option of up to 15 days of unpaid leave
• 25 days of workation within the EU
• Flexible working hours
• Sofa Concerts and employee events
• Discounts on ticket purchases & opportunities for clearing assignments
• Corporate benefits and discounts at KESS
• Central location & subsidy for a Job Ticket or Germany Ticket
• Bike leasing
• Mental health program & company pension scheme
• “GoFluent” language learning platform as well as Lunch & Learn sessions

We value diversity and treat all applications equally – regardless of gender, background, age, religion, disability, or sexual orientation. Different perspectives enrich our team and make EVENTIM stronger.