René Wilby | Freelance Software Engineer

Hi, my name is

René.

I'm a seasoned freelance software engineer.

My main focus is on development of full-stack web apps, microservices, APIs and DevOps stuff.

About Me

I’m a generalist. In my professional career, I have already fulfilled many different roles. At heart, I was and still am a software engineer.

I’m curious and always eager to learn new things. I like to analyse complex problems and issues in order to design solutions that help people.

Here are a few technologies I've been working with recently:

Java, Kotlin, Spring (Boot, Data, Security)
TypeScript, React
Vaadin, Hilla
Kafka
OpenAPI, REST, SOAP
OAuth, Keycloak, auth0
PostgreSQL, MariaDB
OpenShift, Kubernetes, Helm, Kustomize
Jenkins, Tekton
Splunk, Dynatrace
OpenTelemetry
JavaScript, React Native, Expo
GenAI (GitHub Copilot, Gemini CLI)

Experience

Senior Software Engineer (Freelance) - JYSK

01.2025 - present

Part of an agile development team, owning several microservices, that are responsible for the creation of price labels for approx. 3,000 stores in approx. 30 countries.

Design and development of containerized RESTful microservices using Java, Spring, Kafka, OpenAPI and MariaDB.
Design and development of full-stack web apps using Java, Spring, TypeScript, React and Hilla.
Strong focus on test-driven-development, high code coverage and test-automation using JUnit, Testcontainers, Mockito and others.
Securing access of microservices using OAuth protocol, Keycloak and API gateways.
Responsibility for creating and maintaining of CI/CD tools and pipelines using GitHub, JIRA, Jenkins, Gradle and others.
Responsibility for releasing, operating and monitoring of microservices using Helm, Kustomize, Kubernetes and Splunk.
Usage of GenAI technologies (GitHub Copilot).

Senior Software Engineer (Freelance) - Versicherungskammer Bayern

01.2022 - 12.2024

Part of an agile development team, owning several microservices serving as an integration layer for process automation with the claims settlement of a large public insurance company with 7.000+ employees in Munich.

Design and development of containerized RESTful and SOAP microservices using Kotlin, Spring, Camunda, OpenAPI and PostgeSQL.
Strong focus on test-driven-development, high code coverage and test-automation using JUnit, Testcontainers, Wiremock and others.
Securing access of microservices using OAuth protocol, Keycloak, digital signatures and API gateways.
Responsibility for creating and maintaining of CI/CD tools and pipelines using Bitbucket, JIRA, Tekton, Jenkins, Gradle and others.
Responsibility for releasing, operating and monitoring of microservices using Kustomize, OpenShift, Splunk and Dynatrace.
Maintaining and improving the development environment using Ansible, Vagrant and Shell-Scripting.

Freelance Lecturer & Trainer - DHSH

09.2021 - 12.2024

Teaching mobile application development to students (B.Sc. Computer Science) at a local university using React Native, Expo and JavaScript.
Trainer for mobile application development using React Native, Expo and JavaScript.

Co-Founder & Software Engineer - Timebook

10.2020 - 12.2021

Co-Founding of a local startup called “Timebook”, creating an app for personal communication, time and event management.
Owning the complete software development lifecycle, including the design and development of an iOS and Android app using React Native, Expo and JavaScript.
Responsibility for designing and developing of the corresponding backend using Express, JavaScript and MongoDB.
Responsibility for integrating a payment provider (Mollie) and various third-party APIs into the app and the backend.

Product Manager & Product Owner - FLS

10.2019 - 10.2020

Responsibility for product strategy, roadmap and requirement management process at FLS GmbH.
Supporting the transition to an agile product development process and establishing product ownership.

Previous - Vater Unternehmensgruppe

04.2011 - 09.2019

Business Unit Lead Software Development & Collaboration
- Responsibility for leading a department of 25 employees.
Managing Consultant Mobile & Web
- Conception and development of mobile and web apps
- Architecture and technology consulting
- System integration and API development
- Process analysis and consulting
- Sales support and creation of offers
- Professional mentoring of colleagues and supervision of interns and students