Recommended expert

Timon Ringwald

Database Developer – Research Project – Healthcare Billing

Timon Ringwald
Bielefeld, Germany

Experience

Sep 2025 - Oct 2025
2 months

Database Developer – Research Project – Healthcare Billing

MeQuEn GmbH

  • Optimizing dynamically generated databases for logging
  • Tools: MariaDB, C#, Visual Studio, VMs, Docker, Windows, Linux
Jan 2024 - Aug 2025
1 year 8 months

Backend Developer – Data Exchange Platform

MeQuEn GmbH

  • Developing a RESTful API for creating and managing KVNRs
  • Implementing secure storage and transmission of KVNR data in compliance with data protection regulations (e.g., GDPR)
  • Implementing efficient validation and error handling to ensure correct number generation
  • Integrating a logging mechanism for system operations tracking and auditability
  • Designing and implementing a microservice architecture to integrate various data sources
  • Developing an API gateway solution with Spring Boot for internal and external service communication
  • Implementing synchronization and harmonization methods for consistent data representation
  • Implementing error handling and retry mechanisms for increased reliability
  • Implementing a deletion concept for personal data according to GDPR
  • Tools: Java, Spring Boot, Maven, IntelliJ, Postman, OpenAPI/Swagger, PostgreSQL, OPNsense
Dec 2023 - Mar 2025
1 year 4 months

Administrator – Part-time Projects for Various Clients

MeQuEn GmbH

  • Setting up a wired and Wi-Fi network based on TP-Link Omada with redundant architecture and Wi-Fi mesh for seamless transition
  • Configuring VLANs for segmentation (staff, guests, IoT) and QoS rules for critical applications
  • Installing and maintaining multiple web servers with load balancing, HTTPS via Let’s Encrypt, automated backups, caching (Redis, Memcached) and security measures (SSH hardening, fail2ban, security audits)
  • Building a smart home with Zigbee mesh, automation rules (motion, weather data), encrypted communication and energy-optimized device integration
  • Tools: Linux (Ubuntu Server, Raspberry Pi OS), TP-Link Omada Controller, Wireshark, Nginx, Caddy, Docker, Grafana, Home Assistant, Zigbee, MQTT
May 2023 - Sep 2023
5 months

Backend Developer – Event Software

MeQuEn GmbH

  • Software solution for accrediting event participants
  • Defining interfaces and documenting with Swagger/OpenAPI for an API-first approach
  • Designing and implementing the backend architecture
  • Testing and deploying the solution in the cloud
  • Tools: Java, Spring Boot (microservices), Swagger, MinIO, MariaDB, GitHub, Kubernetes, Linux
Nov 2022 - Nov 2023
1 year 1 month

Backend Developer – Whistleblower Protection Software

MeQuEn GmbH

  • SaaS development for various end customers, product lettly.de
  • Implementing cryptographic procedures according to BSI Standard TR 02102-1
  • Implementing security and access concepts in backend systems
  • Implementing a reporting center according to the Whistleblower Protection Act
  • Integrating Stripe as a payment provider
  • Tools: Java, Spring Boot (microservices), Swagger, MongoDB, MinIO, MariaDB, GitHub, Kubernetes, Linux
Aug 2022 - Apr 2023
9 months

Backend Developer – Voting Software

MeQuEn GmbH

  • SaaS development for various end customers, product ballotly.de
  • Implementation of cryptographic procedures according to BSI Standard TR 02102-1 and Common Criteria (CC)
  • Implementation of business logic according to election regulations
  • Creation of a synchronization concept for a distributed architecture
  • Tools: Java, Spring Boot (Microservices), Swagger/OpenAPI, Redis, SSE, DDA, MinIO, MariaDB, GitHub, Kubernetes, Linux
Jun 2022 - Oct 2024
2 years 5 months

Part-Time Project – Automotive Supplier

MeQuEn GmbH

  • Design of a client-server software architecture for scalability across multiple workstations
  • Development of interfaces to control industrial Zebra label printers
  • Design and implementation of bidirectional data synchronization between the labeling system and MS SQL database
  • Software support and maintenance
  • Tools: IntelliJ, Java, JavaFX, MS SQL, Linux Raspberry Pi OS, Raspberry Pi
Apr 2021 - Apr 2022
1 year 1 month

Fullstack Developer – Plant Monitoring

MeQuEn GmbH

  • Further development of a platform for production support in a distributed machine landscape
  • Development and commissioning of solutions for different equipment generations
  • Technology consulting for new installations
  • Tools: Software architecture (EDA, DDD), Java, Spring Boot, MinIO, MySQL, MongoDB, MQTT, Mail-Proxy & Bridges, C#, Linux
Jan 2021 - Jul 2022
1 year 7 months

Backend Developer – Documentation Tool

MeQuEn GmbH

  • Development of a service app as a documentation and reference tool for machines, projects, real estate & facility management
  • Template-based process documentation to ensure consistent quality
  • Tools: Java, Spring Boot (Microservices), NodeJS, MongoDB, MinIO, MariaDB, GitLab, Docker, Docker-Compose, Linux
Mar 2019 - Dec 2020
1 year 10 months

App Developer – Quality Assurance

MeQuEn GmbH

  • Networked Android app for quality control in road and asphalt construction
  • Design and implementation of the infrastructure and the Android app
  • Mathematical modeling of business logic
  • Tools: Java, Android, BLE, SQLite, GitLab, Confluence, Linux
Jul 2018 - Mar 2019
9 months

Fullstack Developer – process management

MeQuEn GmbH

  • Further development of a platform for process optimization and management in agriculture and forestry businesses
  • Technology consulting
  • Tools: Software architecture (EDA, DDD), Java 8, Angular, NodeJS, Apache Cassandra, MariaDB

Summary

Digitalization and software development that add value - from the first idea to the final solution. I enjoy finding the right solutions together with my clients! On the web, I'm at home in the backend - interfaces are my strength.

Core activities: developer, software architect.

Industries: industry, plant engineering and packaging, health insurance, road construction and maintenance, agriculture and forestry, safety-critical infrastructure, cyber security.

Skills

  • Software Development: Java (12 Years), Spring Boot / Microservices (5 Years), Vb.net (4 Years), Winforms (4 Years), Javascript (7 Years), Node.js (2 Years), Typescript (2 Years), Vb6 (5 Years), C# (5 Years), Go (8 Years), Rust (2 Years), C/c++ (3 Years), Bash (6 Years)
  • Databases: Ms Sql (3 Years), Postgresql (5 Years), Redis (2 Years), Sqlite (3 Years), Mariadb (10 Years), Mysql (10 Years), Mongodb (5 Years), Minio (3 Years), Graphql (1 Year)
  • Data Expertise: Geodata, Database Design, Database Optimizations
  • Operating Systems: Linux (15 Years) => Bash, Sh, Daemon Development, Ubuntu, Debian, Arch Linux, Embedded Linux, Raspberry Pi Os
  • Operating Systems: Windows (10 Years) => Powershell, Automated Testing With Junit, Postman
  • Interfaces: Rest, Swagger, Openapi, Stripe, Paypal
  • Other Tools & Techniques: Docker, Docker Compose, Mqtt, Git, Github Including Build Pipelines, Jira, Confluence, Vs Code, Jetbrains Ides, Mail Proxies & Bridges, Grafana, Tp-link Omada, Vlan, Zigbee, Nginx, Caddy, Bsi Standard Tr 02102-1
  • Methodologies: Scrum, Kanban, Waterfall

Languages

German
Native
English
Advanced

Education

Jul 2014 - Jul 2018

b.i.b. International College Bielefeld

Professional training in application development · Bielefeld, Germany

Certifications & licenses

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