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TB©2026

Software Developer & Designer · CS Student

ThomasBreindl

Building robust backend systems, event pipelines, and interfaces people enjoy using. Currently studying CS in Passau, Germany.

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Software EngineeringInterface DesignDistributed Systems
Legacy ModernizationSelf-Hosted InfrastructureData Visualization
/01

About

I build software end to end: migrating decades-old COBOL into modern Java services, designing event pipelines that move millions of messages a day, and crafting interfaces that people actually enjoy using.

06+

Years writing JavaScript

05+

Years shipping Java

03

Professional roles

/02

Experience

01

itestra

Software Developer · Intern → Working Student

  • Reengineered ~21K LOC of legacy COBOL health-insurance logic in Java/Quarkus, migrating batch flows to chunk-oriented Jakarta Batch/JBeret and reducing code size by 40%
  • Built an annotation-driven Java library that turns binary COBOL copybook data into typed objects, eliminating repetitive parsing across the codebase
Mar - Jul 2025 · Oct 2025 - Present
02

CHECK24

Software Engineer · Intern

  • Designed an ActiveMQ/JMS pipeline deferring non-critical provider calls off the initial request path, improving response time and downstream load
  • Cut production P95 latency by 50% to ~150ms across 1.5M daily events, instrumented with Micrometer/Prometheus and Grafana SLO dashboards
Aug - Sep 2025
03

4process

Software Developer · Intern

  • Built an internal idea database with SAP Fiori Elements to streamline proposal and workflow management
  • Developed a Java tool for SAP Sales Cloud exporting HTML records to Excel, validating >5K bulk edits per second before applying
Jul - Aug 2024
/03

Selected Work

©2023

Stratosphere Mission

FrontiersToSpace

Web platform visualizing sensor data from a stratospheric balloon mission, built with the German Amateur Radio Club (DARC) and the Passau Observatory. I owned the frontend and site architecture, and helped build and program the probe itself: sensor integration and APRS data transmission on a TTGO T-Beam.

©2021

E-Commerce Platform

BetterGaming

An e-commerce platform for video games with Ajax-powered live search, sorting, and dynamic product data served by PHP and MySQL. User management built on hashed & salted passwords with client-side validation for secure registration and login.

©2020

Micro Framework

JustHTML

A lightweight framework that simplifies building simple websites: ready-made CSS classes and JavaScript functions used directly in HTML, drastically reducing the need for separate scripts and stylesheets.

©2020

Product Concept

Griffin Energy

A fictional product built from scratch: brand concept, packaging designed in Photoshop, a photorealistic 3D can modeled and rendered in Blender, and a responsive website integrating the renders through animation.

/04

Stack

Backend

  • Java
  • Spring Boot
  • Quarkus
  • JPA / Hibernate
  • Node.js
  • Python
  • SQL

Frontend

  • TypeScript
  • React
  • Next.js
  • SolidJS
  • Astro
  • Tailwind

Infrastructure

  • Docker
  • Kubernetes
  • Terraform
  • GitHub Actions
  • Grafana
  • PostgreSQL

Self-Hosted

  • NixOS
  • Proxmox
  • Traefik
  • WireGuard
  • Ansible
SpokenGerman · NativeEnglish · C1Latin · Latinum

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