Senior Fullstack Engineer

Further development and maintenance of a complex sales platform focusing on digital closing processes, customer portal interactions, and document generation for financial and insurance products

Development and upkeep of microservices with Spring Boot 3 and Kotlin

Frontend development with Angular 20, especially for displaying products, applications, and documents

End-to-end testing with Playwright

Integration tests with WireMock to isolate external dependencies

Creation and optimization of Quartz jobs and CronJobs

Refactoring of the security configuration in a multi-realm Keycloak setup with a custom filter chain, permission evaluator, and factory routing based on path structure

Generation of dynamic emails with Thymeleaf

Extensive debugging using Application Insights, Log Analytics, and direct SQL debugging

Introduced a dynamically configurable security architecture with flexible token handling based on path and realm

Stabilized and clearly structured the closing process, especially for complex product models with main and sub-products

Significantly improved code maintainability and readability through modular refactorings

Increased test stability and depth by combining Playwright, WireMock, and integration tests

Targeted performance optimization through analysis of Hibernate statistics, query tuning, and use of SQL execution plans for efficient database access

Java 21

Kotlin

Spring Boot 3

Angular

TypeScript

REST API

JSON

Kubernetes

Docker

PostgreSQL

Liquibase

Keycloak

OAuth2

GitHub Actions

Testcontainers

Azure Application Insights

Thymeleaf

Tilt

Microsoft SQL Server

Revolutionized the traditional retail customer business by developing fully digital solutions for heating cost billing and smoke detector management

Designed and built cloud-native backend systems on the Azure platform

Implemented microservices with Spring Boot 3 and Java 17/19 to support digital business processes

Integrated various third-party systems (Heiztec, Ortec, SAP, Microsoft Calendar, CRM) for seamless data flows

Developed GraphQL interfaces for efficient data communication between systems

Created Kubernetes configurations

Designed and implemented complex business logic for billing and device management processes

Implemented Azure Functions in the cloud

Collaborated on frontend development with React to create intuitive user interfaces

Successfully digitized the retail customer business through the integration of multiple third-party systems

Significantly increased process automation in heating cost billing and device management

Migrated the entire system to Kubernetes, resulting in improved scalability and maintainability

Developed Azure Functions for efficient cloud-based data management

Java 17/19

Spring Boot 2/3

Azure Cloud

Terraform

Docker

Kubernetes

Helm

Grafana

PostgreSQL

Cosmos DB

MS SQL

Drools (BRMS)

GraphQL

React

GitLab CI

Testcontainers

SOAP

XML

WSDL

REST API

Application Insights

Enhanced a cloud-based data lake and integration platform to support digital transformation at DB Regio Bus

Analyzed and assessed data quality, then performed transformations for data cleansing

Designed and implemented a Java-based microservice for processing CSV and XML files

Adapted and optimized existing Python and Groovy modules to meet new requirements

Developed a Groovy script to automate user import into the Tenfold system

Integrated security measures with Keycloak

Containerized the developed services with Docker

Successfully implemented and deployed a Java microservice for efficient CSV and XML file processing

Automated user imports into the Tenfold system with a newly developed Groovy script, eliminating manual CSV imports

Adjusted multiple Python modules to new business requirements, increasing platform flexibility and functionality

Improved data quality and integration through targeted transformation and cleansing processes

Java 8

Spring Boot 2

Python

Groovy

JavaScript

Linux Shell

Keycloak

Docker

Tenfold

SOAP

REST API

XML

JSON

Development of a central event-driven system to automate and optimize the onboarding process for new merchants at Unzer GmbH

Backend development using Java and Spring Boot 2

Frontend development using Angular 8 and Bootstrap 4

Implementation of complex business logic for the onboarding process

Integration of Keycloak to secure components using OpenID Connect

Modeling and implementation of business processes with Flowable

Setting up and optimizing Continuous Integration and Deployment (CI/CD) pipelines

Development and integration of AWS services (DynamoDB, SQS, SNS, S3)

Successful launch of the MVP in September 2020, enabling self-onboarding for merchants

First successful processing of merchants through the new system at the end of September 2020

Continuous expansion by connecting additional payment providers and end systems

Refined risk assessment capabilities for enhanced security

Full automation of merchant processing for partners via MOSH

Java 8

Spring Boot 2

Angular 8

Bootstrap 4

AWS (DynamoDB, SQS, SNS, S3)

Elastic Beanstalk

Flowable

Keycloak

Docker

Kubernetes

Testcontainers

GitLab

Jenkins

SonarQube

Postman

Jira

Confluence

OAuth2

REST API

JSON

Further development and customization of the CBSI platform for automated integration of business processes in the customer care and billing area

Backend development with Java 7 and Java EE

Implementation and optimization of business logic

Developing new and extending existing web services

Frontend development with JavaServer Faces and ICEfaces

Customizing and extending C++ adapters

Migrating selected C++ adapters to Java

Development of shell scripts for processing CSV files

Assisting with the rollout and deployment of new features

Successfully extended and adapted several C++ adapters to meet new requirements

Migrated specific C++ adapters to Java to improve maintainability and integration

Implemented new Java EE web services to expand platform functionality

Further developed existing web services to optimize business process integration

Created an efficient shell script for automated processing of CSV files

Improved user interfaces for system administrators and service providers

Java 7

Java EE

C++

JBoss

Hibernate

Oracle DB

JavaServer Faces

ICEfaces

HTML

CSS

JavaScript

Linux Shell

SED

IntelliJ IDEA

Subversion

SOAP

XML

JSON

REST API