Skills

Programming

PHP

JavaScript

Python

Methods

Test Driven Development (TDD)

Agile

PHP Frameworks

Laravel

Symfony

Frontend

CSS

JavaScript

jQuery

Bootstrap

Tailwind

Vite

Vue.js

Development-Tools

Git

Subversion

Composer

DDEV

PHPStorm

VSCode

DataGrip

Databases

MySQL

MariaDB

SQLite

DuckDB

TimescaleDB

PostgreSQL

CMS

Kirby CMS

Wordpress

Serendipity

TYPO3

Server

Linux

Docker

Apache2

Projects (selection)

  • PHP 8

  • PHP 5

  • MariaDB

  • Git

  • Codeception

Online tool for radio program planning

An existing application for managing large music databases was prone to errors and became increasingly slow as the volume of data grew. It also lacked modern features for efficient radio program planning. After a thorough analysis of the proprietary framework, I fixed critical bugs and significantly improved the performance of database accesses in some cases. Over several years, I adapted the application to new PHP versions up to 8.4, which significantly improved stability, speed, and security. In addition, I switched to Composer for modern dependency management.

Tasks
  • Migration from PHP 5 to current PHP versions (up to 8.4)
  • Performance optimization of complex database queries
  • Bug fixes and optimization of the proprietary framework
  • Introduction of Composer for dependency management

  • Kirby CMS

  • PHP 8

  • Stripe

  • PayPal

  • Bootstrap

  • Javascript

Publisher website with shop and payment connection

The existing publishing website was completely redesigned and implemented using the modern Kirby CMS. In addition, an integrated shop for print and digital products with a subscription function was created. PayPal and Stripe were successfully integrated for payment processing.

Tasks
  • Implementation of an online shop for print products and subscriptions in Kirby CMS
  • Integration of PayPal and Stripe as payment providers
  • Development of customer-specific Kirby plugins to extend CMS functionality

  • PHP 8

  • MariaDB

  • Bootstrap

B2B shop for interior design manufacturers

As part of an agile team, I gradually expanded the existing system and migrated it to a current software stack.

Tasks
  • Expansion of the B2B shop with numerous functionalities
  • Connection of external shop systems and APIs
  • Newsletter dispatch via CleverReach

  • Laravel

  • MySQL

  • PostgreSQL

  • DuckDB

  • Vue.js

  • Javascript

Marketing and analytics backend for online job board

A central synchronization solution including backend was developed for marketing purposes, enabling the precise control and display of job advertisements to third parties. The range of functions has grown significantly over the years, and numerous external systems have been connected.

Tasks
  • Creation of a web interface for the administration of complex processes
  • Data import and transformation from various sources such as data lakes and analytics tools
  • Generation of customized exports on the fly
  • Real-time data analysis for the customer dashboard

  • Flow Framework

  • Doctrine

Workflow management for business processes

To connect an Angular front end, I designed and implemented a REST interface (JSON API), mapped specific process workflow logic, and created the corresponding database model.

Tasks
  • Creation of customized REST interfaces for the front end
  • Database design and connection
  • Modeling of process workflow logic

  • Symfony

  • Doctrine

  • PHP 7

  • Domain Driven Design

Customer portal for video streaming services

Based on domain-driven design principles, I supported the SCRUM team in expanding the existing application, particularly with regard to payment logic, and in developing the REST interface (API).

Tasks
  • Expansion of payment logic to include additional payment methods
  • Expansion of the REST interface for internal processes

  • Zend Framework

  • Doctrine

  • PHPUnit

Intranet platform for car manufacturer

In an agile process, the existing platform was expanded and stabilized in several sprints. One focus was on quality assurance and improvement measures to avoid errors and increase code quality. A messaging system was initially introduced as an MVP and later fully integrated into the application.

Tasks
  • Introduction of PHPUnit tests locally and on the CI server
  • Monitoring of code quality metrics
  • Implementation of a messaging system

  • OroCRM

  • Symfony

  • Doctrine

Backend for airport asset management

To enable the management of diverse assets in a complex application, the Symfony-based tool OroCRM had to be expanded to include a tiered rights system and individual process logic. The product makes most of the data available in a distributed microservices architecture via a REST interface. Working in a small team, I successfully implemented these requirements using an agile process.

Tasks
  • Implementation of the complex database structure in MySQL using Doctrine
  • Test-driven development of process logic and rights management
  • Performance optimization of the application

  • TYPO3

  • PHP 5

Web interface for mobile phone provider

For a German mobile phone provider, the TYPO3 CMS was expanded with a PHP application to enable the publication of customized content and the mapping of business processes related to mobile phone contracts.

Tasks
  • Application expansion and maintenance
  • Test-driven development of new features

  • Symfony

  • Doctrine

  • Javascript

Custom online store

For a mail order company specializing in sporting goods, the team created a B2B shop that was precisely tailored to the business processes and included, in particular, finely tuned product filtering. Another key feature was the option for customers to customize items to a high degree before placing their orders.

Tasks
  • Complete creation of the shop system in backend and frontend
  • Complex filter logic for product search and display