MID/SENIOR Software Developer Android

Job description

We conceptualize and develop software solutions for Android and iOS. We thoroughly analyze our clients’ issues to provide them with extra value. As an Android developer, you will be working as part of our team to develop new apps as well as to maintain and refine existing client apps.


At Karlmax Berlin, fixed teams work using cross-functional and agile methodologies on client projects from different industries. Even small projects are done as a team and so profit from all developer’s know-how. In everyday work, we use processes following SCRUM and Kanban and thereby continually work on improving them in an iterative fashion. For quality and flexibility, we implement code reviews, continuous integration and automated tests.

These days, new Android projects start in Kotlin. Maintenance of existing projects is in some cases still continued in Java. The last couple of years we shipped our first Flutter apps.

We organize our tasks in Jira, or partly with other systems that our clients use. For source code management, we rely on Git and the workflow Gitflow. Code review is performed before integrating a feature branch. We implement continuous integration with Jenkins and deliver test versions via HockeyApp and the Google Play Alpha channel. For testing we apply an appropriate combination of Unit Tests, Espresso tests and manual tests on various devices in our test device pool.

When developing for Android, we use Retrofit for accessing REST-APIs. Some of our recent projects use ViewModels and LiveData, Room, Data Binding, Koin and Android KTX. Kotlin Coroutines have replaced rxJava for most use cases. Some projects follow the Model-View-Presenter pattern, others Model-View-Viewmodel or Clean Architecture. Sometimes prototypes or projects of a very short lifespan may “Keep it simple”.

More important than perfection in the tools and frameworks mentioned above is your openness and ability to learn. Some apps are developed from scratch and you are involved in defining the architecture from day 1. Other projects have an existing code base and we improve them along with adding new features and updates.

In addition, you will carry new developments and trends into the team. On acquiring a new project, input from our teams is an important part of the estimation process and offer. This is how we incorporate the technical side of a new project from the very beginning. We plan our work for the long term with everyone involved, so that work-life balance is not an empty promise.


  • Work contract from 30 to 40 hours per week, depending on your personal preference
  • Flexible working times with core hours
  • A modern-equipped workplace with a MacBook and a customizable desk environment
  • Development opportunities such as time for exploring new APIs, frameworks and tools; or by attending conferences
  • A central, spacious office directly on Gleisdreieck Park with very good transportation connections
  • Bike locker room with shower
  • Coffee, water, fruit and comfort food for those times when only sugar helps

Job requirements


  • Career experience as professional app developer – some companies may call this level senior, some mid level
  • Experience with Kotlin and Java, at least one expert level
  • Expert knowledge of Android frameworks and tools, object-oriented design as well as the desire to “stay on the ball“
  • Striving for clear software architecture, combined with the ability to explain and establish new standards in the team
  • Strong communication skills
  • English fluency and at least basic German with willingness to improve
  • The readiness to listen to clients and the ability to understand them and to put yourself in the place of their users
  • Desired, but not required: Experience with software development for other platforms
  • Senior: Experience as team lead or lead developer and in customer relations

If this position looks good to you, then we would like to get to know you. Write us what we should know about you. How do you like to work? Under which conditions do you work best? We are looking forward to authentic people who are fun to work with in a multidisciplinary team.

We are looking forward to your application. Please use the "Apply-Button" and upload your CV. Also, let us know what you expect from your future employer. Please also include when you can start as well as your salary expectations.