Senior AWS Cloud Engineer & Technical Lead / Golang / NodeJS / Java Android and Flutter Lead Developer
Aktualisiert am 28.02.2025
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 28.02.2025
Verfügbar zu: 100%
davon vor Ort: 100%
AWS
Back-End
Cloud
Android
Flutter
Go
Node.js
Java
Teamleading
SystemArchitektur
Testing/QS/QM
Python
Azure
.net
.NET 4.6
C#
Agile Softwareentwicklung
Scrum
Kanban
ETL
Deutsch
Muttersprache
Englisch
Verhandlungssicher

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 Jahr
2024-03 - heute

Upgraded the C# .NET backend to the latest version

Technical Lead Technical Planning Teamlead Architecture ...
Technical Lead
  • Led the offshoring team for a delivery app startup, ensuring smooth collaboration and high-quality development.
  • Upgraded the C# .NET backend to the latest version, improving performance and security.
  • Enhanced tracing, caching, and optimized EF Core usage to improve efficiency and maintainability.
  • Refactored and cleaned up legacy code while migrating infrastructure from Azure to AWS.
  • Utilized AWS for hosting, managing infrastructure with Terraform and GitLab for automation and scalability.
  • Served as Cloud Architect, overseeing serverless architecture and managing various AWS resources.
  • Defined and discussed technical requirements for upcoming features, ensuring alignment with business goals.
  • Implemented legal and compliance-related updates, including CoBD regulations.
  • Maintained and enforced high code quality standards across the development team.
Azure Devops MS Teams Figma
Technical Planning Teamlead Architecture AWS Azure Vue.JS Angular Apps Ionic Framework C# .NET
broetchen.taxi GmbH
Bocholt
2 Jahre
2023-03 - heute

Scallable AWS Cloud Farming Services

Cloud Engineer Go Python makefile ...
Cloud Engineer
  • Leading the technical team for Bayer's Crop Division in the remote reconfiguration of the central data hub service.
  • Orchestrating a complete rewrite of version 2 into micro-services utilizing Golang for optimal functionality.
  • Leveraging AWS platform for hosting, with management through the use of Terraform and GitHub.
  • Holding the role of Cloud-Architect, managing serverless alongside a range of AWS resources.
  • Developing GraphQL and Rest API, ensuring seamless integration and streamlined data exchange.
  • Implementing existing Cognito service for user authentication and authorization.
  • Providing mission-critical central eventing implementation for CPIL with AWS-native tools
  • Platform development for CPIL in both Go and Pythoin
  • Leading the successful migration process to GitHub for enhanced collaboration and version control.
AWS GitHub Go Terraform Architekt Testinfrastruktur Testing/QS/QM Microservices Amazon RDS DocumentDB Azure Devops
Go Python makefile Terraform AWS Amazon RDS XML Linter End-To-End-Test Eventing
BAYER Crop Science
Remote
5 Jahre 2 Monate
2020-01 - heute

Founded and developed a cross-platform app

Owner & Dev Flutter Go NextJS ...
Owner & Dev
  • Founded and developed a cross-platform app and web service focused on affiliate marketing, SEO, and web scraping, fully hosted on AWS.
  • App (Flutter):
    • Built for iOS & Android with BloC & Provider, supporting tablet & phone layouts, and dark/light mode
    • Integrated Firebase Push, dio, rxdart, built_value, json_serializable
  • Backend (Golang):
  • Backend:
    • Developed using Gin, uber/fx, logrus, gorm, with PostHog, NewRelic, and RevenueCat for analytics and monetization
    • Fully hosted on AWS across separate dev & prod accounts
    • Utilized SNS, SQS, Lambda, API Gateway, CloudFront, Cognito for scalability, Elasticsearch
  • Web (NextJS):
    • Developed and optimized using NextJS
    • Implemented SEO strategies and JSON-LD for better search rankings
  • Web Scrapers (NodeJS):
    • Built scrapers using Cheerio, cron, fastify, promise
    • ?Self-hosted and deployed with Docker for automation and data extractionw
GitHub Figma
Flutter Go NextJS AWS Founder Web Scraping Affiliate Marketing SEO Elasticsearch
on request
Berlin
9 Monate
2022-08 - 2023-04

Migrating services from AWS to an on-premise environment

Backend Engineer Golang NodeJS Testing ...
Backend Engineer
  • Collaborated with a remote team to centralize IAM solutions for a Swedish company.
  • The project was built on a microservices architecture, originally hosted on AWS.
  • Responsibilities included:
    • Migrating services from AWS to an on-premise environment
    • Updating and maintaining Terraform configurations for AWS infrastructure
    • Implementing Kubernetes with K-native to create a serverless-like environment for on-premise deployments
    • Establishing and optimizing networking between AWS and on-premise systems
    • ?Developing and enhancing Golang and NodeJS microservices
MS Teams Atlassian JIRA GitLab
Golang NodeJS Testing IAM Development AWS Cognito Lambda K-native Kubernetes GCP Kubernetes On-Premise Cloud networking Kafka
Telia Sweden
Remote
7 Monate
2022-06 - 2022-12

Cross-platform tracking solutions

X-Platform Tracking Dev NodeJS Golang Kotlin ...
X-Platform Tracking Dev
  • Worked on cross-platform tracking solutions for RTL+, focusing on backend development in NodeJS and Golang and contributing to the Android SDK in Kotlin while ensuring GDPR compliance.
  • The project involved building, deploying, and maintaining scalable tracking services.
  • Backend Development:
    • Developed a generic middleware in Golang to validate request payloads against Schema.json definitions
    • Implemented and maintained tracking-related microservices in NodeJS and Golang
  • Cloud Infrastructure & Deployment:
    • Managed Kubernetes deployments using HELM
    • Configured CI/CD pipelines in GitLab CI for automated testing and deployments
    • Deployed services to AWS using Terraform
  • Android SDK Development:
    • Contributed to the Android tracking SDK using Kotlin
    • Integrated tracking features to ensure compatibility with backend services
  • Compliance & Testing:
    • Ensured GDPR-compliant data handling for tracking services
    • ?Developed and maintained automated testing frameworks to improve reliability
GitLab Atlassian JIRA
NodeJS Golang Kotlin Android Tracking GDPR Kubernetes HELM GitLab CI AWS Testing Kafka
RTL+ Tracking
Remote
1 Monat
2022-06 - 2022-06

Golang Workshops

Trainer Go Workshop Trainer
Trainer
  • Led over 10 Golang workshops at Sipgate/Telekom since 2022, each spanning 12 hours and tailored to participants' skill levels, covering both fundamental and advanced Golang topics.
  • Admin Workshop:
    • Covered Golang fundamentals, including data types, control structures, and goroutines
    • Focused on automation, operations tasks, SQL, and HTTP server implementation
  • Developer Workshop: Taught Golang basics, from data types to goroutines
  • Conducted deep dives into:
    • Service architecture with REST & GRPC
    • Worker pools and concurrency patterns
    • Leak detection and debugging tools
    • ?Industry best practices for scalable Golang applications
Go Workshop Trainer
Sipgate/Telekom
Remote
1 Jahr 8 Monate
2020-10 - 2022-05

System Architecture

CTO / Backend Lead Spring CTO Team Lead ...
CTO / Backend Lead
  • As CTO and Backend Lead, I was responsible for system architecture, cloud infrastructure, and team leadership, reporting directly to the CEO. I led backend development with a focus on Spring Kotlin & Golang, overseeing hiring and technical strategy.
  • Golang:
    • Built 8 microservices using gRPC & gRPC-Gateway, managing inter-service communication with buf.build
    • Implemented JWT authentication with Keycloak and integrated MongoDB & Redis
    • Managed CI/CD pipelines in GitLab CI, deploying to Kubernetes
    • Used an AWS Kubernetes cluster using Terraform
    • Evaluated and selected Golang over .NET Core for scalability and performance
  • Spring Kotlin:
    • Refactored Golang microservices into Spring Boot services
    • Set up Gradle with Kotlin, integrating MongoDB & Redis
    • Developed unit, integration, and end-to-end tests to ensure system resilience
    • Additionally, I was responsible for cloud architecture on AWS, strategic technical decisions, and team hiring and leadership
GitHub
Spring CTO Team Lead Hiring System-Architecture Cloud AWS Reporting to CEO Spring Boot Kotlin Golang
Internet Value / PLAYT.net
Düsseldorf
1 Jahr
2021-01 - 2021-12

App development

Freelance Mobile Lead Technical Teamlead Hiring iOS Staffing ...
Freelance Mobile Lead
  • As Freelance Mobile Lead, I oversaw the development of the new Fressnapf app for both Android and iOS, while also handling technical leadership, hiring, staffing, cross-team communication, UX/UI involvement, and Agile rollout
  • Android Development:
    • Implemented MVI architecture with Kotlin Flow, adhering to TDD & Clean Architecture principles
    • Designed a modular architecture for scalability and maintainability
    • Integrated Retrofit, Hilt, ConstraintLayout, and Material Design for an intuitive user experience
  • iOS Development:
    • Built the iOS version using SwiftUI, structured with separate frameworks for modularity
    • Followed Clean Architecture principles and testing protocols to ensure stability and efficiency
Atlassian JIRA Atlassian Confluence GitLab
Technical Teamlead Hiring iOS Staffing Cross-Team-Communication Product involvement UX / UI Agile Android Lead Developer
Fressnapf
remote
9 Monate
2020-04 - 2020-12

Kijiji Android App

Freelance Android Senior Android Testing Agile Scrum ...
Freelance Android Senior
  • Contributed to the development of the Kijiji Autos Android app, focusing on architecture, modularization, and CI/CD to enhance maintainability and performance
  • Implemented MVVM, DataBinding, and Kotlin Flow following Clean Architecture principles
  • Designed a modular app structure for scalability and feature isolation
  • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient data handling and UI consistency
  • Worked in feature teams to improve development workflows and cross-team collaboration
  • Ensured Continuous Integration (CI) for reliable, automated testing and deployment
Atlassian JIRA GitLab
Android Testing Agile Scrum Product Focus Release Management Shared Plattform development Kotlin
Mobile.de / eBay
Berlin
3 Monate
2020-01 - 2020-03

Gesundheitsplattform

Lead Android Developer Teamlead Testing Release Management Android ...
Lead Android Developer
  • Led Android development for the IBM Gesundheitsplattform, focusing on secure health applications, end-to-end encryption, and Germatik compliance. Managed team leadership, testing, and release management while ensuring high standards for healthcare regulations.
  • Architecture & Development:
    • Implemented MVVM, RxJava2, and Clean Architecture with a modular structure
    • Developed SDKs tailored for health insurance companies
    • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient app performance
  • Security & Compliance: Ensured end-to-end encryption and adherence to Germatik health standards
  • Collaboration & Deployment:
    • Worked in feature teams for efficient, cross-functional development
    • Established Continuous Integration (CI) pipelines for a reliable and error-free codebase
Teamlead Testing Release Management Android iOS Health Germatik End to End encryption Offshore Outsourcing
IBM
Hamburg
8 Monate
2019-05 - 2019-12

Contributed to the Kijiji Autos Android app

Freelance Android Senior Android Agile Scrum Product Focus ...
Freelance Android Senior
  • Contributed to the Kijiji Autos Android app, focusing on shared platform development, testing, release management, and Agile Scrum workflows. Ensured high-quality, modular, and scalable architecture while maintaining a strong product focus.
  • Architecture & Development:
    • Implemented MVVM, DataBinding, and Kotlin Flow, adhering to Clean Architecture principles
    • Designed a modular app structure for better maintainability and feature scalability
    • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient UI and data handling
  • Agile & Cross-Team Collaboration:
    • Worked in feature teams to improve development speed and efficiency
    • Focused on shared platform development to ensure compatibility across product lines
  • Testing & Release Management:
    • Established Continuous Integration (CI) pipelines for consistent testing and deployment
    • ?Ensured a coherent, bug-free codebase through automated testing and Agile processes
Android Agile Scrum Product Focus Testing Release Management Shared Plattform development
Mobile.de / eBay
4 Monate
2019-01 - 2019-04

Contributed to the Android app

Android Senior Android Android Java / Kotlin Flutter Prototyping ...
Android Senior
  • Contributed to the Eurowings Android app, focusing on maintainable architecture, aviation-specific requirements, and early Flutter prototyping.
  • Android Development:
    • Developed in Java & Kotlin, ensuring a robust and scalable codebase
    • Followed Clean Architecture principles, implementing MVP (Model-View-Presenter) for structured UI interactions
    • Integrated Retrofit for secure and efficient network operations
    • Used Dagger for dependency injection and improved modularity
  • Prototyping & Innovation: Explored Flutter for potential cross-platform solutions, assessing feasibility for aviation-related applications
Android Android Java / Kotlin Flutter Prototyping Aviation
Eurowings Digital GmbH
1 Jahr 4 Monate
2017-09 - 2018-12

Lieferservice Android apps

Android Senior Android Migration from Java to Kotlin Modular Clear Architecture ...
Android Senior
  • Worked on the PENNY and REWE Lieferservice Android apps, focusing on migrating from Java to Kotlin, modular architecture, and dependency injection. Led product development and Firebase hosting for PENNY, ensuring scalable and maintainable applications.
  • PENNY App:
    • Implemented Coroutines, Conductor, and Katana, following Clean Architecture principles
    • Developed Instant Apps for a lightweight and seamless user experience
  • REWE Lieferservice App:
    • Structured the app using MVP (Model-View-Presenter) with Dagger and Retrofit
    • Followed Clean Architecture to ensure maintainability and scalability
Android Migration from Java to Kotlin Modular Clear Architecture Dependency Injection with Dagger Firebase Hosting for Penny Product Development
REWE digital GmbH
2 Monate
2017-10 - 2017-11

Developed an Android finance application

Freelance Android Project Android Design Finance
Freelance Android Project
  • Developed an Android finance application, focusing on scalability, clean architecture, and efficient data handling.
  • Android Development:
    • Built the app using Kotlin with Dagger 2 for dependency management
    • Followed Clean Architecture principles and implemented MVP (Model-View-Presenter) for structured data flow
    • ?Integrated Retrofit for seamless and secure network communication
Android Design Finance
Fundamental Capital GmbH
3 Monate
2017-06 - 2017-08

Developed features

Android Senior Android
Android Senior
  • Developed features for the MapTrip Navigation Android app, focusing on real-time GPS navigation, performance optimization, and asynchronous data handling.
  • Integrated GPS and navigation components for real-time location tracking and routing
  • Utilized NDK to optimize performance-critical sections of the app
  • Implemented RxJava for efficient asynchronous operations and data streams
Android
MapTrip Navigation

Aus- und Weiterbildung

Aus- und Weiterbildung

4 Jahre 11 Monate
2012-08 - 2017-06

Bachelor of Science Informatik ? Media informatics

Hochschule Bonn-Rhein-Sieg, Sankt Augustin
Hochschule Bonn-Rhein-Sieg, Sankt Augustin
11 Monate
2009-08 - 2010-06

Bachelor of Science - Software Engineering

Fontys International Campus, Venlo
Fontys International Campus, Venlo
2 Jahre 11 Monate
2006-08 - 2009-06

Informationstechnischer-Assistent

Berufskolleg Bocholt-West, Bocholt
Berufskolleg Bocholt-West, Bocholt

Kompetenzen

Kompetenzen

Top-Skills

AWS Back-End Cloud Android Flutter Go Node.js Java Teamleading SystemArchitektur Testing/QS/QM Python Azure .net .NET 4.6 C# Agile Softwareentwicklung Scrum Kanban ETL

Schwerpunkte

Golang
Experte
AWS
Experte
NodeJS
Fortgeschritten
Android
Experte
Flutter
Experte
Java
Experte
Kotlin
Experte
Rust
Fortgeschritten
Python
Fortgeschritten
GitHub
Experte
Cloud
Experte

Produkte / Standards / Erfahrungen / Methoden

WORK SKILLS

  • Golang
  • Python
  • AWS
  • Terraform
  • NodeJS / Typescript
  • Testing, Testsuits, E2E
  • Android / Flutter
  • CI / CD
  • Java / Kotlin / Spring
  • C# / .NET
  • Docker & Kubernetes
  • Git
  • Unreal Engine 4 & Unity


WORK EXPERIENCE

05/2019 - today

Role: Senior Freelancer/Technical Lead

Customer: Bocholt


10/2020 - 06/2022

Role: Backend Lead Developer

Customer: PLAYT.net AG, Düsseldorf


Tasks:

During the time at PLAYT.net I have built a Golang microservice backend & Spring Boot services based on the initial requirements. Both frontend and backend teams are currently working on a gaming-platform with focus on real money games. 


01/2019 - heute

Role: Senior Android Developer

Customer: Eurowings Digital GmbH, Köln


Tasks:

Eurowings Digital was founded in 2018. I've started to work in the current app in the beginning of 2019. While working with an external company who built the app, I coordinated the work between the teams.


09/2017 - 12/2018

Role: Senior Android Developer

Customer: REWE digital GmbH, Köln


Tasks:

While working for REWE I maintained their delivery app and built the new PENNY app from scratch. Both apps were written in Kotlin and included dependency injection and testing. In addition the PENNY app uses Conductor and an in-house developed dependency injection framework called ?Katana".


01/ 2017 - 09/2017

Role: Android Development

Customer: Pausanio GmbH & Co. KG, Köln


Tasks:

At Pausanio I worked on several Android apps for customers from the culture industry. In addition I maintained the server infrastructure and introduced GitLab and Docker.


2016 - 2016

Role: Fullstack Entwickler

Customer: Dembach Goo Informatik GmbH & Co. KG, Köln


Tasks:

For the DG-I I implemented an internal eCommere solution in Node.js for banks. Another project used an external API which calculated GEO-risk data through a PWA.


2013 - 2015

Role: Working Student Android Development

Customer: grandcentrix GmbH, Köln


Tasks:

While working for grandecentrix I worked on app for our customers and also built new app from scratch. Some of the customers were AXA, Clipfish (RTL), the Finanzinformatik and OBI.


2011 - 2013

Role: Java EE Development

Customer: Prosystems IT GmbH, Bonn


Tasks:

At Prosystems IT I implemented a company-wide SSO solution with Java EE.


LATEST PROJECTS

03/2023 - today

Role: Cloud Lead Engineer

Customer: BAYER Crop Science


Tasks:

  • Leading the technical team for Bayer's Crop Division in the remote reconfiguration of the central data hub service.
  • Orchestrating a complete rewrite of version 2 into micro-services utilizing Golang for optimal functionality.
  • Leveraging AWS platform for hosting, with management through the use of Terraform and Gitlab.
  • Holding the role of Cloud-Architect, managing serverless alongside a range of AWS resources.
  • Developing GraphQL and Rest API, ensuring seamless integration and streamlined data exchange.
  • Implementing existing Cognito service for user authentication and authorization.
  • Leading the successful migration process to GitHub for enhanced collaboration and version control.


Skills:

AWS, Golang, Gitlab, GitHub, GraphQL 


2020 - today

Role: Founder 

Customer: on request


Tasks:

  • As the sole founder, I'm actively developing a new app with Flutter, available on Apple Store and Google Play Store, using technologies like BloC & Provider, Firebase Push and others for ultimate user experience.
  • Also responsible for the backend development using Golang, I utilize AWS services for both development and production.
  • I've enhanced our web presence with a website developed using NextJS with a focus on SEO optimization.
  • Lastly, I've implemented NodeJS web scrapers hosted on Docker for efficient data collection.


Skills:

Flutter, Node.js, Golang, AWS, MongoDB, OneSignal, RevenueCat


08/2022 - 04/2023

Role: Backend Engineer 

Customer: Telia Sweden


Tasks:

Serving as a Backend Engineer on a remote team for Telia Sweden, assisting in centralizing their IAM solutions via a microservices architecture hosted on AWS. My responsibilities include:

  • Transitioning from AWS to an on-premise based implementation for several services.
  • Revamping Terraform configurations tailored to AWS.
  • Augmenting Goland and NodeJS microservices with new features.


Skills:

AWS, Golang, Nodejs, IAM


06/2022 - 06/2022

Role: Trainer for Golang Workshops 

Customer: Sipgate


Tasks:

  • Led two Golang workshops each consisting of 12 hours, covering basic and advanced topics depending on the group's focus.


Skills:

Flutter, Node.js, Golang, AWS, MongoDB, OneSignal, RevenueCat


10/2020 - 05/2022

Role: Backend Lead 

Customer: Internet Value / PLAYT.net


Tasks:

  • In the role of Backend Lead, I oversaw the development of the backend, mainly focusing on Spring Kotlin & Golang.


Skills:

Golang, Spring, Nakama, NextJS, Kubernetes, Azure, Redis


2021 - 2021

Role: Freelance Mobile Lead 

Customer: Fressnapf App


Tasks:

  • I lead the development of the new Fressnapf app for both Android and iOS. We decided to use MVI for Android and MVVM with SwiftUI for iOS. 
  • Besides leading the mobile development, I also worked with other departments to define requirements for our services as well as future features.


Skills:

iOS & Android

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 Jahr
2024-03 - heute

Upgraded the C# .NET backend to the latest version

Technical Lead Technical Planning Teamlead Architecture ...
Technical Lead
  • Led the offshoring team for a delivery app startup, ensuring smooth collaboration and high-quality development.
  • Upgraded the C# .NET backend to the latest version, improving performance and security.
  • Enhanced tracing, caching, and optimized EF Core usage to improve efficiency and maintainability.
  • Refactored and cleaned up legacy code while migrating infrastructure from Azure to AWS.
  • Utilized AWS for hosting, managing infrastructure with Terraform and GitLab for automation and scalability.
  • Served as Cloud Architect, overseeing serverless architecture and managing various AWS resources.
  • Defined and discussed technical requirements for upcoming features, ensuring alignment with business goals.
  • Implemented legal and compliance-related updates, including CoBD regulations.
  • Maintained and enforced high code quality standards across the development team.
Azure Devops MS Teams Figma
Technical Planning Teamlead Architecture AWS Azure Vue.JS Angular Apps Ionic Framework C# .NET
broetchen.taxi GmbH
Bocholt
2 Jahre
2023-03 - heute

Scallable AWS Cloud Farming Services

Cloud Engineer Go Python makefile ...
Cloud Engineer
  • Leading the technical team for Bayer's Crop Division in the remote reconfiguration of the central data hub service.
  • Orchestrating a complete rewrite of version 2 into micro-services utilizing Golang for optimal functionality.
  • Leveraging AWS platform for hosting, with management through the use of Terraform and GitHub.
  • Holding the role of Cloud-Architect, managing serverless alongside a range of AWS resources.
  • Developing GraphQL and Rest API, ensuring seamless integration and streamlined data exchange.
  • Implementing existing Cognito service for user authentication and authorization.
  • Providing mission-critical central eventing implementation for CPIL with AWS-native tools
  • Platform development for CPIL in both Go and Pythoin
  • Leading the successful migration process to GitHub for enhanced collaboration and version control.
AWS GitHub Go Terraform Architekt Testinfrastruktur Testing/QS/QM Microservices Amazon RDS DocumentDB Azure Devops
Go Python makefile Terraform AWS Amazon RDS XML Linter End-To-End-Test Eventing
BAYER Crop Science
Remote
5 Jahre 2 Monate
2020-01 - heute

Founded and developed a cross-platform app

Owner & Dev Flutter Go NextJS ...
Owner & Dev
  • Founded and developed a cross-platform app and web service focused on affiliate marketing, SEO, and web scraping, fully hosted on AWS.
  • App (Flutter):
    • Built for iOS & Android with BloC & Provider, supporting tablet & phone layouts, and dark/light mode
    • Integrated Firebase Push, dio, rxdart, built_value, json_serializable
  • Backend (Golang):
  • Backend:
    • Developed using Gin, uber/fx, logrus, gorm, with PostHog, NewRelic, and RevenueCat for analytics and monetization
    • Fully hosted on AWS across separate dev & prod accounts
    • Utilized SNS, SQS, Lambda, API Gateway, CloudFront, Cognito for scalability, Elasticsearch
  • Web (NextJS):
    • Developed and optimized using NextJS
    • Implemented SEO strategies and JSON-LD for better search rankings
  • Web Scrapers (NodeJS):
    • Built scrapers using Cheerio, cron, fastify, promise
    • ?Self-hosted and deployed with Docker for automation and data extractionw
GitHub Figma
Flutter Go NextJS AWS Founder Web Scraping Affiliate Marketing SEO Elasticsearch
on request
Berlin
9 Monate
2022-08 - 2023-04

Migrating services from AWS to an on-premise environment

Backend Engineer Golang NodeJS Testing ...
Backend Engineer
  • Collaborated with a remote team to centralize IAM solutions for a Swedish company.
  • The project was built on a microservices architecture, originally hosted on AWS.
  • Responsibilities included:
    • Migrating services from AWS to an on-premise environment
    • Updating and maintaining Terraform configurations for AWS infrastructure
    • Implementing Kubernetes with K-native to create a serverless-like environment for on-premise deployments
    • Establishing and optimizing networking between AWS and on-premise systems
    • ?Developing and enhancing Golang and NodeJS microservices
MS Teams Atlassian JIRA GitLab
Golang NodeJS Testing IAM Development AWS Cognito Lambda K-native Kubernetes GCP Kubernetes On-Premise Cloud networking Kafka
Telia Sweden
Remote
7 Monate
2022-06 - 2022-12

Cross-platform tracking solutions

X-Platform Tracking Dev NodeJS Golang Kotlin ...
X-Platform Tracking Dev
  • Worked on cross-platform tracking solutions for RTL+, focusing on backend development in NodeJS and Golang and contributing to the Android SDK in Kotlin while ensuring GDPR compliance.
  • The project involved building, deploying, and maintaining scalable tracking services.
  • Backend Development:
    • Developed a generic middleware in Golang to validate request payloads against Schema.json definitions
    • Implemented and maintained tracking-related microservices in NodeJS and Golang
  • Cloud Infrastructure & Deployment:
    • Managed Kubernetes deployments using HELM
    • Configured CI/CD pipelines in GitLab CI for automated testing and deployments
    • Deployed services to AWS using Terraform
  • Android SDK Development:
    • Contributed to the Android tracking SDK using Kotlin
    • Integrated tracking features to ensure compatibility with backend services
  • Compliance & Testing:
    • Ensured GDPR-compliant data handling for tracking services
    • ?Developed and maintained automated testing frameworks to improve reliability
GitLab Atlassian JIRA
NodeJS Golang Kotlin Android Tracking GDPR Kubernetes HELM GitLab CI AWS Testing Kafka
RTL+ Tracking
Remote
1 Monat
2022-06 - 2022-06

Golang Workshops

Trainer Go Workshop Trainer
Trainer
  • Led over 10 Golang workshops at Sipgate/Telekom since 2022, each spanning 12 hours and tailored to participants' skill levels, covering both fundamental and advanced Golang topics.
  • Admin Workshop:
    • Covered Golang fundamentals, including data types, control structures, and goroutines
    • Focused on automation, operations tasks, SQL, and HTTP server implementation
  • Developer Workshop: Taught Golang basics, from data types to goroutines
  • Conducted deep dives into:
    • Service architecture with REST & GRPC
    • Worker pools and concurrency patterns
    • Leak detection and debugging tools
    • ?Industry best practices for scalable Golang applications
Go Workshop Trainer
Sipgate/Telekom
Remote
1 Jahr 8 Monate
2020-10 - 2022-05

System Architecture

CTO / Backend Lead Spring CTO Team Lead ...
CTO / Backend Lead
  • As CTO and Backend Lead, I was responsible for system architecture, cloud infrastructure, and team leadership, reporting directly to the CEO. I led backend development with a focus on Spring Kotlin & Golang, overseeing hiring and technical strategy.
  • Golang:
    • Built 8 microservices using gRPC & gRPC-Gateway, managing inter-service communication with buf.build
    • Implemented JWT authentication with Keycloak and integrated MongoDB & Redis
    • Managed CI/CD pipelines in GitLab CI, deploying to Kubernetes
    • Used an AWS Kubernetes cluster using Terraform
    • Evaluated and selected Golang over .NET Core for scalability and performance
  • Spring Kotlin:
    • Refactored Golang microservices into Spring Boot services
    • Set up Gradle with Kotlin, integrating MongoDB & Redis
    • Developed unit, integration, and end-to-end tests to ensure system resilience
    • Additionally, I was responsible for cloud architecture on AWS, strategic technical decisions, and team hiring and leadership
GitHub
Spring CTO Team Lead Hiring System-Architecture Cloud AWS Reporting to CEO Spring Boot Kotlin Golang
Internet Value / PLAYT.net
Düsseldorf
1 Jahr
2021-01 - 2021-12

App development

Freelance Mobile Lead Technical Teamlead Hiring iOS Staffing ...
Freelance Mobile Lead
  • As Freelance Mobile Lead, I oversaw the development of the new Fressnapf app for both Android and iOS, while also handling technical leadership, hiring, staffing, cross-team communication, UX/UI involvement, and Agile rollout
  • Android Development:
    • Implemented MVI architecture with Kotlin Flow, adhering to TDD & Clean Architecture principles
    • Designed a modular architecture for scalability and maintainability
    • Integrated Retrofit, Hilt, ConstraintLayout, and Material Design for an intuitive user experience
  • iOS Development:
    • Built the iOS version using SwiftUI, structured with separate frameworks for modularity
    • Followed Clean Architecture principles and testing protocols to ensure stability and efficiency
Atlassian JIRA Atlassian Confluence GitLab
Technical Teamlead Hiring iOS Staffing Cross-Team-Communication Product involvement UX / UI Agile Android Lead Developer
Fressnapf
remote
9 Monate
2020-04 - 2020-12

Kijiji Android App

Freelance Android Senior Android Testing Agile Scrum ...
Freelance Android Senior
  • Contributed to the development of the Kijiji Autos Android app, focusing on architecture, modularization, and CI/CD to enhance maintainability and performance
  • Implemented MVVM, DataBinding, and Kotlin Flow following Clean Architecture principles
  • Designed a modular app structure for scalability and feature isolation
  • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient data handling and UI consistency
  • Worked in feature teams to improve development workflows and cross-team collaboration
  • Ensured Continuous Integration (CI) for reliable, automated testing and deployment
Atlassian JIRA GitLab
Android Testing Agile Scrum Product Focus Release Management Shared Plattform development Kotlin
Mobile.de / eBay
Berlin
3 Monate
2020-01 - 2020-03

Gesundheitsplattform

Lead Android Developer Teamlead Testing Release Management Android ...
Lead Android Developer
  • Led Android development for the IBM Gesundheitsplattform, focusing on secure health applications, end-to-end encryption, and Germatik compliance. Managed team leadership, testing, and release management while ensuring high standards for healthcare regulations.
  • Architecture & Development:
    • Implemented MVVM, RxJava2, and Clean Architecture with a modular structure
    • Developed SDKs tailored for health insurance companies
    • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient app performance
  • Security & Compliance: Ensured end-to-end encryption and adherence to Germatik health standards
  • Collaboration & Deployment:
    • Worked in feature teams for efficient, cross-functional development
    • Established Continuous Integration (CI) pipelines for a reliable and error-free codebase
Teamlead Testing Release Management Android iOS Health Germatik End to End encryption Offshore Outsourcing
IBM
Hamburg
8 Monate
2019-05 - 2019-12

Contributed to the Kijiji Autos Android app

Freelance Android Senior Android Agile Scrum Product Focus ...
Freelance Android Senior
  • Contributed to the Kijiji Autos Android app, focusing on shared platform development, testing, release management, and Agile Scrum workflows. Ensured high-quality, modular, and scalable architecture while maintaining a strong product focus.
  • Architecture & Development:
    • Implemented MVVM, DataBinding, and Kotlin Flow, adhering to Clean Architecture principles
    • Designed a modular app structure for better maintainability and feature scalability
    • Integrated Retrofit, Dagger2, and ConstraintLayout for efficient UI and data handling
  • Agile & Cross-Team Collaboration:
    • Worked in feature teams to improve development speed and efficiency
    • Focused on shared platform development to ensure compatibility across product lines
  • Testing & Release Management:
    • Established Continuous Integration (CI) pipelines for consistent testing and deployment
    • ?Ensured a coherent, bug-free codebase through automated testing and Agile processes
Android Agile Scrum Product Focus Testing Release Management Shared Plattform development
Mobile.de / eBay
4 Monate
2019-01 - 2019-04

Contributed to the Android app

Android Senior Android Android Java / Kotlin Flutter Prototyping ...
Android Senior
  • Contributed to the Eurowings Android app, focusing on maintainable architecture, aviation-specific requirements, and early Flutter prototyping.
  • Android Development:
    • Developed in Java & Kotlin, ensuring a robust and scalable codebase
    • Followed Clean Architecture principles, implementing MVP (Model-View-Presenter) for structured UI interactions
    • Integrated Retrofit for secure and efficient network operations
    • Used Dagger for dependency injection and improved modularity
  • Prototyping & Innovation: Explored Flutter for potential cross-platform solutions, assessing feasibility for aviation-related applications
Android Android Java / Kotlin Flutter Prototyping Aviation
Eurowings Digital GmbH
1 Jahr 4 Monate
2017-09 - 2018-12

Lieferservice Android apps

Android Senior Android Migration from Java to Kotlin Modular Clear Architecture ...
Android Senior
  • Worked on the PENNY and REWE Lieferservice Android apps, focusing on migrating from Java to Kotlin, modular architecture, and dependency injection. Led product development and Firebase hosting for PENNY, ensuring scalable and maintainable applications.
  • PENNY App:
    • Implemented Coroutines, Conductor, and Katana, following Clean Architecture principles
    • Developed Instant Apps for a lightweight and seamless user experience
  • REWE Lieferservice App:
    • Structured the app using MVP (Model-View-Presenter) with Dagger and Retrofit
    • Followed Clean Architecture to ensure maintainability and scalability
Android Migration from Java to Kotlin Modular Clear Architecture Dependency Injection with Dagger Firebase Hosting for Penny Product Development
REWE digital GmbH
2 Monate
2017-10 - 2017-11

Developed an Android finance application

Freelance Android Project Android Design Finance
Freelance Android Project
  • Developed an Android finance application, focusing on scalability, clean architecture, and efficient data handling.
  • Android Development:
    • Built the app using Kotlin with Dagger 2 for dependency management
    • Followed Clean Architecture principles and implemented MVP (Model-View-Presenter) for structured data flow
    • ?Integrated Retrofit for seamless and secure network communication
Android Design Finance
Fundamental Capital GmbH
3 Monate
2017-06 - 2017-08

Developed features

Android Senior Android
Android Senior
  • Developed features for the MapTrip Navigation Android app, focusing on real-time GPS navigation, performance optimization, and asynchronous data handling.
  • Integrated GPS and navigation components for real-time location tracking and routing
  • Utilized NDK to optimize performance-critical sections of the app
  • Implemented RxJava for efficient asynchronous operations and data streams
Android
MapTrip Navigation

Aus- und Weiterbildung

Aus- und Weiterbildung

4 Jahre 11 Monate
2012-08 - 2017-06

Bachelor of Science Informatik ? Media informatics

Hochschule Bonn-Rhein-Sieg, Sankt Augustin
Hochschule Bonn-Rhein-Sieg, Sankt Augustin
11 Monate
2009-08 - 2010-06

Bachelor of Science - Software Engineering

Fontys International Campus, Venlo
Fontys International Campus, Venlo
2 Jahre 11 Monate
2006-08 - 2009-06

Informationstechnischer-Assistent

Berufskolleg Bocholt-West, Bocholt
Berufskolleg Bocholt-West, Bocholt

Kompetenzen

Kompetenzen

Top-Skills

AWS Back-End Cloud Android Flutter Go Node.js Java Teamleading SystemArchitektur Testing/QS/QM Python Azure .net .NET 4.6 C# Agile Softwareentwicklung Scrum Kanban ETL

Schwerpunkte

Golang
Experte
AWS
Experte
NodeJS
Fortgeschritten
Android
Experte
Flutter
Experte
Java
Experte
Kotlin
Experte
Rust
Fortgeschritten
Python
Fortgeschritten
GitHub
Experte
Cloud
Experte

Produkte / Standards / Erfahrungen / Methoden

WORK SKILLS

  • Golang
  • Python
  • AWS
  • Terraform
  • NodeJS / Typescript
  • Testing, Testsuits, E2E
  • Android / Flutter
  • CI / CD
  • Java / Kotlin / Spring
  • C# / .NET
  • Docker & Kubernetes
  • Git
  • Unreal Engine 4 & Unity


WORK EXPERIENCE

05/2019 - today

Role: Senior Freelancer/Technical Lead

Customer: Bocholt


10/2020 - 06/2022

Role: Backend Lead Developer

Customer: PLAYT.net AG, Düsseldorf


Tasks:

During the time at PLAYT.net I have built a Golang microservice backend & Spring Boot services based on the initial requirements. Both frontend and backend teams are currently working on a gaming-platform with focus on real money games. 


01/2019 - heute

Role: Senior Android Developer

Customer: Eurowings Digital GmbH, Köln


Tasks:

Eurowings Digital was founded in 2018. I've started to work in the current app in the beginning of 2019. While working with an external company who built the app, I coordinated the work between the teams.


09/2017 - 12/2018

Role: Senior Android Developer

Customer: REWE digital GmbH, Köln


Tasks:

While working for REWE I maintained their delivery app and built the new PENNY app from scratch. Both apps were written in Kotlin and included dependency injection and testing. In addition the PENNY app uses Conductor and an in-house developed dependency injection framework called ?Katana".


01/ 2017 - 09/2017

Role: Android Development

Customer: Pausanio GmbH & Co. KG, Köln


Tasks:

At Pausanio I worked on several Android apps for customers from the culture industry. In addition I maintained the server infrastructure and introduced GitLab and Docker.


2016 - 2016

Role: Fullstack Entwickler

Customer: Dembach Goo Informatik GmbH & Co. KG, Köln


Tasks:

For the DG-I I implemented an internal eCommere solution in Node.js for banks. Another project used an external API which calculated GEO-risk data through a PWA.


2013 - 2015

Role: Working Student Android Development

Customer: grandcentrix GmbH, Köln


Tasks:

While working for grandecentrix I worked on app for our customers and also built new app from scratch. Some of the customers were AXA, Clipfish (RTL), the Finanzinformatik and OBI.


2011 - 2013

Role: Java EE Development

Customer: Prosystems IT GmbH, Bonn


Tasks:

At Prosystems IT I implemented a company-wide SSO solution with Java EE.


LATEST PROJECTS

03/2023 - today

Role: Cloud Lead Engineer

Customer: BAYER Crop Science


Tasks:

  • Leading the technical team for Bayer's Crop Division in the remote reconfiguration of the central data hub service.
  • Orchestrating a complete rewrite of version 2 into micro-services utilizing Golang for optimal functionality.
  • Leveraging AWS platform for hosting, with management through the use of Terraform and Gitlab.
  • Holding the role of Cloud-Architect, managing serverless alongside a range of AWS resources.
  • Developing GraphQL and Rest API, ensuring seamless integration and streamlined data exchange.
  • Implementing existing Cognito service for user authentication and authorization.
  • Leading the successful migration process to GitHub for enhanced collaboration and version control.


Skills:

AWS, Golang, Gitlab, GitHub, GraphQL 


2020 - today

Role: Founder 

Customer: on request


Tasks:

  • As the sole founder, I'm actively developing a new app with Flutter, available on Apple Store and Google Play Store, using technologies like BloC & Provider, Firebase Push and others for ultimate user experience.
  • Also responsible for the backend development using Golang, I utilize AWS services for both development and production.
  • I've enhanced our web presence with a website developed using NextJS with a focus on SEO optimization.
  • Lastly, I've implemented NodeJS web scrapers hosted on Docker for efficient data collection.


Skills:

Flutter, Node.js, Golang, AWS, MongoDB, OneSignal, RevenueCat


08/2022 - 04/2023

Role: Backend Engineer 

Customer: Telia Sweden


Tasks:

Serving as a Backend Engineer on a remote team for Telia Sweden, assisting in centralizing their IAM solutions via a microservices architecture hosted on AWS. My responsibilities include:

  • Transitioning from AWS to an on-premise based implementation for several services.
  • Revamping Terraform configurations tailored to AWS.
  • Augmenting Goland and NodeJS microservices with new features.


Skills:

AWS, Golang, Nodejs, IAM


06/2022 - 06/2022

Role: Trainer for Golang Workshops 

Customer: Sipgate


Tasks:

  • Led two Golang workshops each consisting of 12 hours, covering basic and advanced topics depending on the group's focus.


Skills:

Flutter, Node.js, Golang, AWS, MongoDB, OneSignal, RevenueCat


10/2020 - 05/2022

Role: Backend Lead 

Customer: Internet Value / PLAYT.net


Tasks:

  • In the role of Backend Lead, I oversaw the development of the backend, mainly focusing on Spring Kotlin & Golang.


Skills:

Golang, Spring, Nakama, NextJS, Kubernetes, Azure, Redis


2021 - 2021

Role: Freelance Mobile Lead 

Customer: Fressnapf App


Tasks:

  • I lead the development of the new Fressnapf app for both Android and iOS. We decided to use MVI for Android and MVVM with SwiftUI for iOS. 
  • Besides leading the mobile development, I also worked with other departments to define requirements for our services as well as future features.


Skills:

iOS & Android

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