Jan H.

Senior Software Engineer

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Berlin, Germany

Experience

Jan 2025 - Jun 2025
6 months

Senior Software Engineer

Helmholtz Centre for Environmental Research (UFZ)

  • Spearheaded implementation of a new authentication system across PHP backend, Vue.js web application, and Ionic-based iOS/Android mobile apps to ensure compliance with Keycloak security requirements
  • Owned requirements engineering and product roadmap development, aligning technical initiatives with business objectives and stakeholder needs
  • Delivered multiple high-impact features across web and mobile platforms, enhancing user experience and expanding system capabilities
  • Facilitated knowledge transfer through comprehensive documentation and handover processes to ensure continuity of operations
Jul 2021 - Present
4 years 6 months
Berlin, Germany

Technical Founder

Telemarie

  • Conducted trade-off analyses for tech stacks and led the design and implementation of the software architecture, including mobile and backend solutions
  • Facilitated event storming workshops to define solution domains for DDD and architecture
  • Defined overall product and organizational strategic direction and explored new forms like steward ownership
  • Guided adoption of Lean and Agile principles, implemented lean prototypes, and ensured adherence to Lean Startup processes
  • Facilitated workshops, retrospectives, and futurespectives to align team, resolve conflicts, and foster collaboration
  • Technologies: Flutter, Google Cloud, Firebase, Android, iOS, Hexnode MDM, proto.io
  • Organizational Methods: Lean startup, lean canvas, event storming, retrospectives
Jan 2015 - Jun 2021
6 years 6 months

Delivery Lead

Zalon by Zalando

  • Initiated implementation using Scala Play framework with Postgres and AWS and expanded architecture incorporating a microservices strategy
  • Commanded delivery teams in journey from 0 to ~€50M revenue, collaborating with business on tech-critical decisions and nurturing cross-functional teams
  • Held accountability for entire application and system architecture, including microservice strategy, AWS, Kubernetes, and Docker
  • Technologies: Scala, Akka, Scalaz, Scalatest, Play2, Postgres, AWS (EC2, Lambda, RDS, Route53, CloudFront, S3), Kubernetes, Grafana, NewRelic/AppDynamics
  • Organizational Methods: Lean and Agile methodologies, event storming workshops for goal alignment
Mar 2013 - Dec 2014
1 year 10 months

Technical Founder

get2play GmbH

  • Responsible for implementation of platform and coordination of development
  • Defined product and organizational strategic direction and explored steward ownership models
  • Guided adoption of Lean and Agile principles, implemented lean prototypes, and iterated from product/solution-fit to product/market-fit
  • Facilitated workshops, retrospectives, and futurespectives to align team, resolve conflicts, and foster collaboration
  • Technologies: Play2, Scala, JavaScript, WebAudio, jQuery, Heroku, AWS (EC2, S3, Media Services), Mixpanel, MongoDB
  • Organizational Methods: Lean startup, lean canvas, event storming, retrospectives
Apr 2011 - Dec 2012
1 year 9 months

Software Developer

PARSHIP GmbH

  • Developed major improvements of online matchmaking platform and new mobile web application
  • Overhauled legacy modules to object-oriented architecture to improve performance and maintainability
  • Initiated and implemented build and configuration management tools to facilitate continuous deployment
  • Collaborated with team members to ensure code quality and conducted peer reviews
  • Technologies: Java, Microservices
  • Organizational Methods: Agile development, Continuous Integration/Continuous Deployment, Code reviews
Aug 2009 - Mar 2011
1 year 8 months

Software Developer

edict egaming GmbH

  • Created multiplatform desktop Java client for online casino admin and backoffice, ensuring compatibility and performance across operating systems
  • Developed robust automated acceptance tests to validate features and ensure quality assurance prior to deployment
  • Technologies: Java, Java Swing, Java FX, REST APIs
  • Organizational Methods: Agile development, RESTful architecture, Automated Acceptance Testing
Dec 2008 - Aug 2009
9 months

Consultant and Developer

Freelancer

  • Developed ERP modules for Creations Media using Java
  • Consulted at Heitcon3 and Creations Media on system and software architectures, OO analysis and design, TDD, and Scrum
Jan 2007 - Nov 2008
1 year 11 months

Senior Consultant

Steria Mummert Consulting AG

  • Led migration of CRM application suite to web-based SAP applications using SAP WAS (ABAP)
  • Created and executed roadmap for integrated CRM and sales channel management landscape used by 500–1000 users
  • Conducted business process and requirements analysis for solution modeling and implementation
  • Introduced Agile principles and served as Scrum Master for a team of 7 members
  • Provided training and consulting in OO design and system architectures
  • Developed GUI using BSP and HTML and implemented business and data layers using ABAP Objects, Object Services, Open SQL, and XML
  • Technologies: SAP WAS (ABAP), BSP, HTML, Open SQL, XML
  • Organizational Methods: Agile principles, Scrum, Object-Oriented Design, Business Process Analysis
Nov 2004 - Jan 2007
2 years 3 months

Technology Consultant

Accenture

  • Served as Assistant Project Manager for transactional data portal with ~500 users and led development team of 5 members
  • Conducted business process and requirements analysis and functional design
  • Oversaw technical design and implementation of services and change requests using EJBs, ABAP Objects, WebDynpros, and JSPs
  • Crafted technical design for validation module with complex algebra for financial consolidation and custom application for rule definitions
  • Defined data model for rules using XML and XML Schemas and developed business and data layers with Java EJB, JDO, and JAX
  • Technologies: EJB, ABAP Objects, WebDynpros, JSPs, XML, XML Schemas, Java EJB, JDO, JAX
  • Organizational Methods: Project Management, Business Process and Requirements Analysis, Technical Design, Module Design
Aug 2001 - Mar 2004
2 years 8 months

Research Assistant

University of Hamburg

  • Worked in artificial intelligence focusing on knowledge representation and processing to verify theories on human spatial concepts and processes
  • Built virtual robot to interpret textual route descriptions, create internal representations, and navigate within artificial environment
  • Developed application interface and key knowledge representation modules in Java and text-interpretation module in Prolog integrated via C-based interface
  • Used complex geometric framework for artificial environment operations and conclusions
  • Technologies: Java, Prolog, C, Artificial Intelligence, Knowledge Representation

Summary

I'm a hands-on software engineer with deep technical expertise who gets energized by adjacent fields like organizational design, product strategy, and modern work methodologies. My sweet spot: combining solid engineering fundamentals with state-of-the-art approaches to deliver real business value.

  • Technical depth: Backend-focused (Scala, Java, cloud platforms) with T-shaped skills across mobile, frontend, and architecture
  • Business-tech bridge: Strong communication skills that translate between engineering realities and business needs
  • Delivery focus: From startup MVPs to €50M+ products
  • Modern methods: Lean Startup, Agile, DDD, and AI-enhanced development workflows
  • Hands-on leadership: Code, architect, facilitate—whatever gets the job done

I thrive at the intersection of technical excellence and smart business decisions, helping teams navigate complex trade-offs while keeping everyone aligned.

Whether it's technical co-founding, scaling delivery teams, or optimizing how teams work together, I love creating systems and cultures that deliver value fast.

Languages

German
Native
English
Advanced

Education

Oct 1997 - Jul 2004

University of Hamburg

Diploma in Computer Science, major in Knowledge Representation and Processing; minor in Business Administration (Operations · Computer Science · Hamburg, Germany · 1.4

Oct 1993 - Jun 1996

Technical High School G16

Abitur · Hamburg, Germany

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