Patrick W. - AI Software Engineer

Karlsruhe, Germany

Experience

Jan 2025 - Sep 2025

9 months

AI Software Engineer

IppenMedia

Analysis, Consulting, Software Design, Development, Automation, Testing, Deployment.

My main tasks were architecture, development and deployment of various proof-of-concept applications around the integration of current AI interfaces (Conversational, Realtime Voice, Images and Videos).

Through this work, I was able to develop various best practices for the client in working with agentic systems and AI in practice and create code templates.

Programming Languages: Python, Typescript, SQL, Bash
Technologies: FastAPI, FastMCP, Google ADK, Vector Embedding / Databases, RDBMS, PyWay, GraphQL
Products: Supabase, Postgres
Tools: Gitlab, VS Code, PyCharm, Cline, Claude Code
Methods: Kanban

Jun 2024 - Aug 2024

3 months

Lead Developer

E-Commerce Client

Analysis, Development, Automation, Testing, Deployment.

Website with responsive design, optimized for mobile and desktop devices.
Optimized for low data transfer requirements (Green IT).
Integration of Pretix into the page structure.
Setup of the CI/CD Pipeline for deployment on aWebserver via ssh.
Setup and Maintenance of DevOps Environment.
Programming Languages: TypeScript, HTML/CSS
Technologies: Vue.js, Nuxt.js, CI/CD, DevOps, Docker Swarm, Docker Compose
Products: NodeJS, Pretix, Ubuntu Linux
Tools: Gitlab, Nexus Artifact Repository, Intellij IDEA
Methods: Kanban

May 2024 - Nov 2024

7 months

Senior Developer

In-House

Research, Development, CI/CD Automation, Testing.

Developed different Applications for updating my Skill set:

Speech Assistant onWear OS
Speech-to-Speech AI Assistant
Participation in Udemy Class on Kafka Integration into Spring Cloud
SmallWeb Applications for generating images from voice input
SimpleWeb Application for tracking daily achievements
Web Application for configuring and running multiple AI Agents, that discuss with each other
Migration from Gitea to Gitlab
Migration of an Android 3D Viewer for CT Scans in DICOM Format from Java to Kotlin
Tech Stack update of my freelancing website.
Programming Languages: Kotlin, Java, TypeScript, HTML/CSS, SQL, Python
Technologies: Vue.js, Nuxt.js, Spring Boot, Spring Cloud, Ktor, Docker, Kubernetes/Helm, Microk8s, NoSQL, Kafka, Python FastApi, OpenAI (Java), Ollama (Java), Hugging Face, Firebase IAM, Firebase Store, OpenGL/GLSL 3, Android, CI/CD, DevOps, Gitea Actions
AI Models: Mixtral 8x7b Q4, Openai Gpt 4,Whisper, Stable Diffusion (GPU), Parler, Phi 3.5
Products: Eclipse Temurin JDK 21, NodeJS, Ubuntu Linux
Tools: Gitlab, Android SDK, Gitea, Nexus Artifact Repository, Intellij IDEA, PyCharm
Methods: Kanban

May 2024 - Jul 2024

3 months

Consultant for Solution and Software Architecture, Lead Developer

Heidenhain

Analysis, Consulting, Software Design, Development, Automation, Testing, Deployment.

Maintenance Application for enabling automated On-Premise Database Upgrades with failsafe mechanisms.
Derived architectural and technological decisions based on ease of use for maintenance team, functional requirements and customer development team.
Iterative approach from acquiring requirements, development, security and licence checks, documentation on functionality and CI/CD integration to providing a final release package.
Programming Languages: Kotlin, SQL, Powershell
Technologies: GraalVM, CliKt, Vagrant
Products: Eclipse Temurin JDK 21, Postgres,Windows Server 2019
Tools: Gitlab, Nexus Artifact Repository, Intellij IDEA
Methods: Kanban

Oct 2023 - Dec 2023

3 months

Lead Developer

E-Commerce Client

Analysis, Software Design, Development, Testing.

Built SMTP Queue with UI for throttling the sending of mails according to provider limits.
Architecture focus on low memory and cpu requirements in self hosted Cloud Environment.
Programming Languages: Kotlin, TypeScript, HTML/CSS, SQL, Bash
Software Design/Architecture: Microservices, Application Resilience, Clean Architecture, Event Driven, Restful API, Cloud, TLS/SSL/Web Security
Technologies: Spring Boot 3, Spring Boot Test, VueJS, Vuetify, Nuxt.js, Docker, Docker Swarm, Docker Compose, Gitea/Github Actions, Flyway, OpenID Connect, OAuth2.0, Mapstruct, Angus Mail, SubEthaSMTP, CI/CD, DevOps
Products: JDK 21, H2, NPM, Ubuntu Linux
Tools: GIT, Gitea, Nexus Artifact Repository, Intellij IDEA, OWASP, Grype
Methods: Kanban

Jan 2022 - Mar 2024

2 years 3 months

Consultant, Senior Developer

Heidenhain

"Patrick made an invaluable impact on our software development processes, team dynamics, and overall project success. His technical expertise, leadership, and problem-solving abilities were key to the successful evolution of our project and our team."

Head of Product Development

Development Process Optimization, Training, Development, Architecture Consulting, CI/CD Automation, Testing.

Implementation of a full stack web application involving complex 3D algorithms and highly asynchronous calculations.
Migration of some algorithms from a Python to Java and integration of native Libraries.
Consulting on architecture of overarching platform and preparing integration into On-Premise Cloud Environment.

Improved overall development throughput by more than 50% through:

adapting git workflow to better fit the project needs
improving and adding missing scrum events
elaborating a positive and productive atmosphere
applying clean architecture rules
setup of customer specific CI/CD environment
applying automated quality goals
enabling junior developers to create high quality code

Enabled team to release at least once every sprint by:

creating common quality understanding and intrinsic quality goals
establish 1-day task sizes
adding automated deployment and e2e testing
elaborating a process for integrating e2e automation into the sprint
adapt software architecture for stabilizing calculations

Stabilized application by:

identifying and closing memory leaks in application code
identifying memory leaks in 3rd party library
extracting unstable 3rd party components into crash-able stateless component, connected via resilience patterns
regular upgrade of Java and Spring Boot (Java 11/17/21; Spring Boot 2.7/3.1/3.2)

Provided specialized Expertise in:

integration of native C++ (JNI) and python libraries (JEP) in Java
computer graphics 3d calculations and (web) visualisation (Three.js)
securing the Application by integration of TLS and OAuth2.0
optimizing algorithms by up to 30% through profiling and introduction of virtual threads
continuous vulnerability and license checks and measures for risk reduction via CI/CD pipelines

Prepared software and team for production phase by:

adding grafana for monitoring and logging
identifying and clarifying possible software license issues
enabling team to identify license issues
enabling team to identify and fix security issues
enabling team for Java and Spring Boot Version upgrades
establishing a DevOps mindset in the team

Further mentions:

reduced calculation time by a factor of 1000, from 16 hours down to ~50 seconds
communication with stakeholders for platform integration
consulted Lead Architect of the overarching platform on efficient software design for low profile hardware
identified and acquired high potential team candidates by elaborating a meaningful technical interview process
leading customer workshops on different subjects (technological, methodical)
documentation of architecture and process details
Programming Languages: Java, TypeScript, HTML/CSS, SQL, Bash, Python
Software Design/Architecture: Structured Monolith, Microservices, Application Resilience, Clean Architecture, Restful API, On-Premise Cloud, TLS/SSL/Web Security
Technologies: Spring Boot 3, Spring Boot Test, Java Virtual Threads, React, Next.js, Docker, Docker Swarm, Docker Compose, Jenkins Pipeline Scripting, Flyway, Java DJL, 3D Maths, OpenID Connect, OAuth2.0, C++ Makefile, JNI, gRPC, protobuf, CI/CD, DevOps
Products: Eclipse Temurin JDK 21, Postgres 16, NodeJS, Ubuntu Linux 22, Ory Hydra, Prometheus, Grafana, Loki, RHEL, Podman
Tools: GIT, Jenkins, Sonarqube, Jfrog Artifact Repository, Intellij IDEA, Confluence, BitBucket, Docker Desktop,WSL, OWASP, Grype
Methods: Scrumban-like approach

Aug 2019 - Dec 2021

2 years 5 months

Consultant, Senior Developer

DXC/Daimler

Consulting,Workflow-Optimization, Training, Software Architecture, Development, CI/CD Automation, Testing.

Migration from a mostly monolithic spring boot application from OpenShift to a cloud-native application on AWS.

Quality Improvement of the application, making sure it meets the requirements and standards of the latest customer software development guidelines.

Established a process for achieving the goal:

Analysis of Quality and Methodology and Improvement of Development Process
Consulting and Supporting Project Manager and Product Owner on the Development Process and Methodologies.
Introduction of a CI/CD Infrastructure based on Infrastructure as Code (IaC) and optimizing performance
Setup of MicroK8s Cluster as Environment for CI/CD Pipelines
Integration of automated Quality, Vulnerability and License scans
Setup of Microk8s Cluster for staging and testing as similar as possible to the target environment
Supporting Development Team to improve quality via leading by example and introduction of Quality Gates into the process
Optimization of test performance for achieving goals in time
Optimization of test coverage and coaching the team on better testing
Introduction of helm charts as replacement for manual kubernetes deployments
Setup of test and integration environments via IaC
Extension of Build Pipeline for automated deployment on integration environment
Coaching of the team on workflow improvement (SAFe + Git)

Actual implementation:

Migration from Spring Boot 1.5 with Java 8 to Spring Boot 2.7 with Java 11 and Spring Cloud
Carve-out of Microservice from Monolithic Application for reduction of cpu and memory requirements of the single components
Rework of multithreaded and event based services for cloud environments and adding test coverage
Introduction of Resilience Patterns mandatory for Cloud Environments
Introduction of Monitoring and Logging endpoints and connecting them to central Kibana instance
Migration of FTP Endpoint to S3 Buckets
Cleanup Code according to clean coding guidelines to gain development speed
Introduction of state-of-the-art software development guidelines for scaling development speed
Migration of Active MQ and Infinispan
Migration from Postgres to RDS
Performance Profiling and Identification and Resolving of major Bottleneck
Introduction of concepts for assuring data consistency across whole application
Documentation as code (mkdocs, plantuml)
Programming Languages: Java, HTML/CSS/Javascript, SQL
Software Design/Architecture: Migration to Microservices, Anti-corruption Layer, Application Resilience, Clean Architecture, Restful API, Cloud, TLS/SSL/Web Security, Events
Technologies: Spring Boot 2, Spring Boot Test, Liquibase, Docker, Kubernetes, Helm Charts, Docker Swarm, Docker Compose, Jenkins Job DSL, Jenkins Pipeline Scripting, BitBucket API, Terraform, XML/XSLT/XQuery/XPath, Cloud (Iaas, CaaS), CI/CD, DevOps
Products: AWS EKS, AWS IAM, AWS S3 Buckets, AWS RDS, Postgres, Oracle JDK 8, Amazon Corretto JDK 11, Infinispan, Active MQ
Tools: GIT, Jenkins, Sonarqube, Nexus Artifact Repository, Intellij IDEA, Confluence, BitBucket, MicroK8s, PlantUML, mkdocs, OWASP
Methods: SAFE, Scrum, Kanban

Feb 2019 - Jul 2019

6 months

Senior Developer

Governikus

Conception, Development, Documentation, Testing.

Java 11 Consulting and Development of JavaFX Based Application with Outlook Integration for reading and answering Mails with xJustiz Receipt Attachment.
Load- and Performance Testing of an Integration Environment with some Mocked Services.
Development of a JMeter Plugin as Load Provider.
Adapter that Fetches E-Mails via IMAP and stores these Mails into a Long Term Storage System.
Programming Languages: Java
Technologies: Java 11, JavaFX, Java Mail, Spring Boot, Spring Integration, TLS/SSL, Digital Signature, Encryption, Resilience4J, JUnit, Mockito
Products: OpenJDK 11, Jacob, YAJSW,WIX Toolset, OpenJFX, Apache JMeter
Tools: Mercurial, Review Board, Jenkins, Sonarqube, Intellij IDEA
Methods: Kanban

Sep 2014 - Dec 2014

4 months

Developer

In-House

Conception, Development, Performance Optimization.

Concept and Development of an Android App for displaying 3D Volume Data (e.g. DICOM Images) using a Raycasting Shader on an Nvidia Shield Tablet. Private Project as a proof of concept.

Programming Languages: Java
Technologies: Android Java, OpenGl ES 3.0
Products: Android 6.0
Tools: Eclipse, Android SDK

Apr 2014 - Jan 2019

4 years 10 months

Senior Developer, Junior Architect

medavis GmbH

Project: Radiology System Integration via HL7 and DICOM**

Conception, Development, Documentation, Testing, Performance Optimization, Architecture (Re-)Design, Modernization (Java 8 Migration).

Integration of a Radiology Information System into the System Environment of multiple Radiologies and Hospitals.

Programming Languages: Java, Groovy (for testing), SQL, PL/SQL
Technologies: TLS/SSL, JUnit, Mockito, Socket Communication, Swing
Products: SAP SQL Anywhere, Tanuki ServiceWrapper, Jetty
Tools: SVN, Jenkins, Sonarqube, Intellij IDEA
Methods: SCRUM
Project: Radiology System Services**

Conception, Development, Documentation, Testing, Performance Optimization, Architecture Design.

Extension of a Radiology Information System via multipleWebServices that provide access to modern Functions and APIs such as:

SMS Appointment Notifications
LDAP
CDA
eArztbrief
VSDM
Document Repositories
KV-Safenet
Process Automation
Programming Languages: Java, Groovy (for testing), SQL, PL/SQL, HTML/CSS/Javascript
Technologies: Java EE, XML/XSLT, JPA, CDI, LDAP, EJB, JTA, TLS/SSL, JUnit, Mockito, Digital Signature
Products: jQuery, Bootstrap, Knockout JS, Apache TomEE, Active MQ, Apache Camel, Hibernate, SAP SQL Anywhere, Tanuki ServiceWrapper
Tools: SVN, Jenkins, Sonarqube, Intellij IDEA, OWASP, Postman
Methods: SCRUM

Jan 2010 - Mar 2014

4 years 3 months

Professional Systems Engineer, Developer, Consultant, Senior Developer, Architect

T-Systems International GmbH

Project: Extension of a transport logistics application (06/2010 - 03/2014)**

Conception, Development, Documentation, Testing, Performance Optimization, Replacement of IBM RAD with Eclipse, Introduction of Continuous Integration.

Step-by-step reimplementation and replacement of a COBOL application using Java EE.

Programming Languages: Java, SQL, PL/SQL
Technologies: Java EE, JPA, JSP, Servlets, EJB, JAX-RS, XSLT, Caching
Products: IBMWebsphere Application Server 7 (zOS), IBM MQ (zOS), IBM DB2 (zOS)
Tools: SVN, Jenkins, Eclipse, IBM RAD, Sparx Enterprise Architect
Methods: Kanban
Project: Reimplementation of a COBOL application in Java EE (04/2013 - 03/2014)**

Conception, Development, Documentation, Testing, Performance Optimization.

Performance-critical supply-chain backend application written COBOL reimplemented using Java EE.

Programming Languages: Java, SQL, PL/SQL
Technologies: Java EE, JPA, EJB, JAX-RS, XSLT, Caching, Code Generators, PAI
Products: IBMWebsphere Application Server 8.5 (Unix), IBM MQ, Oracle 18c
Tools: SVN, Jenkins, Sonarqube, Eclipse
Methods: Kanban
Project: Transition of multiple projects (01/2010 - 05/2010)**

Reconstruction and analysis of the software architecture.Weakness analysis. Transferring the knowledge to 3rd Level Support in India.

Transition of 3 out of about 80 projects to a common IT service desk for 3rd-level-support and development of enhancements.

Programming Languages: Java, SQL, PL/SQL, HTML/CSS/Javascript, VBA, Unix Bash Scripting
Technologies: UML, Java EE, JPA, EJB, JAX-RS, JAX-B, Caching, PAI, SOAP
Products: IBMWebsphere Application Server, IBM MQ, IBM DB2, Hibernate, Oracle, MS Access
Tools: SVN, Jenkins, Eclipse, IBM RAD, Sparx Enterprise Architect, SoapUI

Jan 2009 - Dec 2010

2 years

Engineer

Keybird IT

Jan 2009 - Mar 2009

3 months

Developer

In-House

Concept, Development, Documentation, Testing.

Implementation of a Convoluted Neural Network on Graphics Hardware using OpenGL.

Programming Languages: C++, GLSL
Technologies: OpenGL, 3D Maths, CNN, Artificial Intelligence
Products: Ubuntu

Oct 2008 - Dec 2008

3 months

Project Manager, Architect, Developer

In-House

Team Lead, Project Management, Requirement Specification, Concept, Development, Documentation, Testing.

Idea and project lead of the data warehouse: A distributed and modular data warehouse system for a non-profit health care project. Persistence Layer and all mappings towards it are completely generated based on an ontology.

Programming Languages: Java, SQL
Technologies: UML, Java EE, EJB, Ontology, Code Generators
Products: JBoss Application Server 6, Hibernate, Postgres, Ubuntu
Tools: SVN, Eclipse, Ant

Apr 2008 - Aug 2008

5 months

Developer

In-House

Concept, Development, Documentation, Testing.

Enhancement of the Viewer for multidimensional Volume Data. Added GLSL Support, with example Shaders: Phong Shading and a Ray-Casting engine.Added a 3-dimensional rotatable clipping plane, that also works with the GLSL.

Programming Languages: C++, GLSL
Technologies: OpenGL, Ray Tracing, Ray Casting, 3D Maths
Products: Kubuntu
Tools: g++, vim, make

Jul 2006 - Jul 2008

2 years 1 month

Karlsruhe, Germany

Scientific Assistance

Fraunhofer IITB Karlsruhe

Concept, Development, Documentation, Testing.

Added features: RSS-Feed, generic Input Forms based on an Ontology Structure, JavaScriptWidgets for browsing an Ontology on top of an annotated text.

Programming Languages: Java, SQL, HTML/CSS/Javascript
Technologies: eJava, XML, XSLT
Products: Apache Tomcat, mySQL, MS Access
Tools: CSV, Eclipse

Summary

Professional and elaborate Development of custom tailored software solutions
Consultation on software architecture, modernization and migration of performance-critical legacy software
Guidance on development methods, processes and team workflows
Hands-on training for most relevant technologies

Benefit from more than 15 years of professional software development experience and over 25 years hands-on practice.

As a seasoned software development expert with a strong foundation in Java as well as experience across multiple other programming languages, I empower teams to excel throughout the entire software lifecycle. From initial requirements to deployment and beyond, I provide deep technical guidance and cross-cutting business insight. I enable your teams to build adaptable, future-proof solutions, that seamlessly align technical execution with business objectives, ensuring long-term success.

My goal is to make a long-lasting and positive impact on your team, your customers, and everyone involved in the lifecycle of your products or services.