Fullstack Software Engineer

9/2022 – 3/2023

New backend infrastructure for dealing with carbon credits persisted on blockchain
(Definition of architecture, interfaces and data flows. Implementation of backend microservices that handle blockchain data for carbon credits and provide consumer facing API)
-Hyperlink entfernt-
Golang, Gin, Ginkgo, MicroService, Docker, AWS, CDK, TypeScript, ECS, Fargate, GraphQL, REST, OpenAPI, Postgres

Service security architecture
(Designing and implementing token based authentication and roles- and permission concept to meet special customer requirements. Providing a consumer facing API)
Golang, Gin, Ginkgo, MicroService, Docker, JWT, AWS, CDK, TypeScript, ECS, Fargate, REST, OpenAPI, Postgres

New search service for projects tokens
(Aggregation of different sources using GraphQL)
Golang, Gin, Ginkgo, MicroService, Docker, AWS, CDK, TypeScript, ECS, Fargate, GraphQL, REST, OpenAPI, Postgres

New service for users and accounts
(Designing and implementing microservice and infrastructure for maintaining accounts and users tailored to meet special requirements. Implementing various flows for user handling by leveraging SendGrid)
Golang, Gin, Ginkgo, MicroService, Docker, JWT, SendGrid, AWS, CDK, TypeScript, ECS, Fargate, REST, OpenAPI, Postgres

Software Architecture, Software engineering / -technik

3/2022 – 8/2022

Shipment Tours for Customs
Implementing new features in a microservice architecture for shipment tours for customs.
(Kotlin, Java, Python, Spring Boot, AWS, Kubernetes, Docker, Postgres, OpenAPI, REST, Kanban)

Softwareentwicklung (allg.)

11/2021 – 3/2022

Federated API for Accommodations
Design and implementation of federated API for accommodations using GraphQL with Apollo Federation and mircoservices, drive architectural solutions and decisions, present results to stakeholders, introduce global types de facto standard to accommodation service
(Java, Spring Boot, Typescript, GraphQL, Apollo Federation, AWS, CDK, ECS, EKS, Docker, Kubernetes, Postgres, SNS, SQS)

Accommodation Manager Application
Create web application for maintaining accommodations
(React, Typescript, NodeJS, Jest, HTML, CSS, Storybook, OpenAPI)

Data analysis
Analyzing data from different sources using Python
Python
Common Platform for Content about Accommodations
Building and extending Microservices for creating a new platform for accommodation content.
(Java, Go, Spring Boot, AWS, CDK, ECS, EKS, Kubernetes, Docker, OpenAPI, SNS, SQS, Postgres)

Softwareentwicklung (allg.)

11/2020 – 9/2021

User Identity Services Migration
Migration of existing monolithic service to new microservice architecture in AWS
(Kotlin, Java, Python, JavaScript, AWS, AWS Cloud Formation, AWS Lambda, Spring Boot,Github Actions, Docker)

Introduction of DynamoDB as new Database Technology
Research of different database technologies based on given requirements, creating PoC, coaching the team and implemention to use DynamoDB
(Spring Boot, Reactive Programming, AWS, DynamoDB, DocumentDB, Amazon RDS, Aurora, MongoDB, Cloud Formation)

Migration of different user flows
Migration of different existing flows based on new architecture
(React, Kotlin, AWS, Lambda, S3, Serverless, Cloud Formation, Github Actions)

Migration IP-Blocklist
Rework existing IP-Blocklist generator
(Python, AWS, Lambda, S3, Serverless, Cloud Formation, Github Actions)

Amazon Web Services (AWS), CSS (Cascading Style Sheet), Docker, Git, Gradle, HTML5, Java (allg.), JavaScript, Junit, Kotlin, Python, Softwareentwicklung (allg.)

1/2020 – 10/2020

Entwicklung von Microservices für ein neues Produkt

(RESTful Services, Java, Groovy, Spring Boot, Gradle, Maven, Oracle, Splunk,
JUnit, Spock, Vagrant, Quartz, Encryption, DKIM-Signature, PKI, Puppet)

Oracle Database, Git, Gradle, Java (allg.), Junit, Softwareentwicklung (allg.), Spring Framework, Puppet, Virtualbox, Kotlin, Representational State Transfer (REST)

9/2019 – 12/2019

Fraud Management Tools
- Development and maintenance of existing infrastructure
- Java, Groovy, Spring Boot, AWS Cloud, Docker, Gradle, PostgreSQL, JUnit, RESTful Service, Apache Kafka

Authentication system migration
- Switch internal tool to a new single sign on service
- Java, Spring Boot, SAML, Single Sign On using Okta

Integration risk assessment service
- Integration of risk bureau service into internal tool for different countries
- Java, Groovy, Spring Boot, RESTful Service

Postgresql, Confluence, Docker, Git, Gradle, J2EE, Java SE, Java (allg.), Jenkins, Jira, Junit, Spring Framework, Amazon Web Services (AWS)

5/2019 – 3/2023

Online Service for freelancers - setup infrastructure
(Design a web portal for supporting freelancers. Create backend infrastructure in the cloud, set up build pipeline and continuous deployment. Implement user management and corresponding flows, e.g. registration)
Golang, Gin, React, TypeScript, AWS RDS, AWS Aurora, S3, KMS, Encryption, CDK, Docker, MySQL, REST, OpenAPI, Bootstrap, HTML, CSS, DroneIO

Online Service for freelancers - time tracking and invoicing
(Define architecture, design and implement time tracking and invoicing)
Go, Gin, React, TypeScript, AWS RDS, AWS Aurora, S3, KMS, Encryption, CDK, Docker, MySQL, REST, OpenAPI, Bootstrap, HTML, CSS

Online Service for freelancers - profile generation and CRM
(Design and implement service for generating profiles for freelancers and customer relationship management)
Golang, Gin, React, TypeScript, AWS RDS, AWS Aurora, S3, KMS, Encryption, CDK, Docker, MySQL, REST, OpenAPI, Bootstrap, HTML, CSS

Software engineering / -technik

4/2018 – 8/2019

Car trading platform
- Development of microservice architecture for different countries
- Java, Spring, Gradle, Karate, BDD, MongoDB, Hibernate, MySQL, JWT, RESTful Service, KeyCloak, Swagger/OpenAPI, Docker, JUnit, Wiremock, Apache Kafka

Application for managing merchants
- Java, Spring, Gradle, MongoDB, JWT, RESTful Service, KeyCloak, Swagger/OpenAPI, Docker, JUnit, Wiremock

Mongodb, Behavior Driven Development, Confluence, Docker, Git, Gradle, Hibernate (Java), J2EE, Java SE, Java (allg.), Jenkins, Jira, Junit, Spring Framework, Representational State Transfer (REST)

1/2013 – 3/2018

PayPal Working Capital
- Portal extension for merchant loans for german market
- -Hyperlink entfernt-
- Java, JavaScript, AngularJS, NodeJS, KrakenJS, Jasmine, Grunt, REST

Working Capital Administration Tool
- Application for managing merchant loans
- JavaScript, AngularJS, NodeJS, KrakenJS, Single Sign On, Jasmine, Grunt

PayPal Plus
- Generic solution for integrating wallet with different payment providers into shop pages
- -Hyperlink entfernt-
- JavaScript, NodeJS, KrakenJS, Jasmine, Grunt, REST

Component Testing Tool
- Development of a tool to test microservices in PayPal infrastructure and presentation to teams in USA
- Java, Maven, JSON, REST, Oracle

PayPal Rechnungskauf
- Realisierung eines REST-Services in Microservice Architektur
- -Hyperlink entfernt-
- PHP, Phing, REST, JSON

PayPal Payment Checkout
- Umsetzung verschiedener Anforderungen zum PayPal Checkout
- JavaScript, AngularJS, NodeJS

Oracle Database, Confluence, Apache Maven, Git, J2EE, Java (allg.), Jenkins, Node.Js, AngularJS, JavaScript, Json, JavaScript-Frameworks, PHP, Representational State Transfer (REST)

6/2012 – 1/2013

Integration payment provider BillSAFE
- Utilizing PayPal risk engine in BillSAFE
- Java, Spring, Oracle, Stored Procedures, Blaze Rule Engine, PHP, MySQL

Mysql, Oracle Database, Confluence, Apache Maven, Subversion, Git, Java SE, Java (allg.), Jenkins, Spring Framework, PHP, Representational State Transfer (REST)

5/2007 – 5/2012

Development of new CMS for a big publishing company for pharmacy magazines
- CMS for managing different portals
- Java, Grails, Groovy, CAS, SEO

Community functionality for CMS for a big publishing company
- Development of new community functionality based on Enterprise CMS “First Spirit”
- Java, JSP, HTML, Maven, First-Spirit, Single Sign On

Job portal
- Relaunch and feature development
- Java, Spring, Spring Security, Spring Webflow, JSP, SOAP, HTML, CSS

Doctor portal
- Relaunch and feature development
- Grails, Groovy, Hibernate, MySQL, HTML, CSS, JavaScript, SEO

Mysql, Confluence, Apache Maven, Subversion, Git, Grails, Hibernate (Java), Java (allg.), Jenkins, Jira, Spring Framework, SOAP, CSS (Cascading Style Sheet), HTML, JavaScript, Jquery

7/2004 – 8/2004

Further analysis of software for creating and maintaining XML-Interfaces
- development of a prototype for presentation

UML, Java (allg.), Java API for XML Processing (JAXP), XML, CSS (Cascading Style Sheet), HTML, JavaScript

3/2004 – 5/2004

Analysis and planning of software for creating and maintaining XML-Interfaces

UML, XML

10/2002 – 2/2003

Development of components for medical software
- Development of modules as DLLs for Windows

Microsoft Windows (allg.), C++