Jannis Lehmann

Jannis Lehmann

Software Engineer



Hey! My name is Jannis Lehmann and I am a 23 year-old/young software engineer. I love tackling complex projects, which require architectural thinking, planning and working together with colleagues to solve the project with the possibly best solution in the long term.

This January 2021, I concluded my dual studies program, which consisted of the Computer Science Expert - Software Development training and my Business Informatics study program.

During the practical phases at KDO I mainly worked on Java backend applications. Thereby I try to create clean, performant and, most importantly for me, secure code. I also always like to point out new tools and technologies, which we then discussed together and some were also introduced.

Currently, I am working as a backend engineer at Spotify as part of the commerce platform teams.

Within private and/or professional projects, I have worked and tried a lot of technologies so far. I didn’t settle for one programming language.

In my spare time I also spend time away from the computer by working out or spending time with friends. But sometimes I am drawn back to my hobbies, which are (not a complete list though) working on smart home stuff and keeping my server from crashing.

  • Distributed systems
  • Sport
  • Coffee
  • Smart Home
  • B. Sc. Business Informatics, 2017 - 2021

    IT & Business School Oldenburg

  • Computer Science Expert - Software Development, 2017 - 2019

    KDO Service GmbH, IHK Oldenburg

  • High School Graduation, 2017

    Herbartgymnasium Oldenburg


Node.js (JavaScript and TypeScript)


Java and Kotlin






Machine Learning




GitHub Actions


Backend Software Engineer
Apr 2022 – Present Remote
Backend development
Backend Software Engineer
Oct 2021 – Apr 2022 Remote
  • Developed Spring Boot backend applications
  • Architected an IoT message queueing system
  • Improved message handling capacity by at least 1000%
  • Communicated closely with stakeholders
Java Software Engineer
Feb 2021 – Sep 2021 Oldenburg
  • Worked on Java distributed backend applications using Spring Boot
  • Architected Kubernetes cluster for German nation-wide covid vaccination pass Managed a project of 5+ developers undertaking the product owner and lead engineer role
  • Engineered modern software architecture to reliably communicate with thousand of workers
  • Prepared a move to Kubernetes with the development and ops team
  • Critically evaluated new technologies for projects focusing on compliance
Dual studies: Business Informatics - Software Engineer
Aug 2017 – Jan 2021 Oldenburg
  • Built new software architectures using Java with 100% compliance and security best practice
  • Improved application data protection for highly confidential data by implementing a secured REST API
  • Lowered application loading times by 80% by distributing data preparation tasks
  • Bachelor thesis: Introduction of a continuous delivery process using Kubernetes (Grade 1.0)


B. Sc. Business Informatics
Introduction of a continiuous delivery process using Kubernetes
Computer Science Expert - Software Development
Examplary implemention of a REST interface with fokus on security for an existing client-server-application
High School Graduation


CSGO Microservices

Multiple Golang microservices as a port of my csgo tools project, which contains services for consuming Valve’s API, downloading csgo demos etc.

CSGO Tools

A small set of Golang tools, which consume the Valve REST API and act as a Counter-Strike Global Offensive game client to download the recording of a recent match. Furthermore, this toolset offers a tool to analyse the matches and provide information and statistics. A native iOS Swift app is in progress.

Discord Bot

A small Discord bot written in TypeScript, which allows for dynamic voice chat creation by joining a pre-defined channel. It also offers some commands for server admins and moderators.