Marijn Scholtens
Freelance Cloud Software Engineer
Freelance Cloud Software Engineer
Self-Employed
- Project focus: Test automation of customer data management processes
- Client: BMW, on behalf of Riverland Reply GmbH
- Project period: 10.2024 – 02.2025
- Role: Senior Cloud Engineer
- Industry: Automotive
- Set up a self-hosted runner in an EKS cluster using GitHub Actions workflows
- Extended a dashboard to show status of multiple scheduled workflow jobs
- Implemented a monitoring solution with Pushgateway, Prometheus, and Grafana
- Implemented a DynamoDB database for metrics collection
- Team: Agile team with 3 developers and 1 business analyst
- Technologies: GitHub Actions, Kubernetes, EKS, AWS, Terraform, Helm, Secrets Manager, KMS, IAM, CloudWatch, EC2, Session Manager, SNS, Bash, Shell, Python, DynamoDB, prompt engineering with ChatGPT, Jira, Xray, Pushgateway, Prometheus, Grafana, Confluence
Senior Software Engineer
Randstad Digital Germany AG
- Project focus: Backend development for a bank's KYC portal
- Client: (confidential)
- Project period: 11.2023 – 04.2024
- Role: Java backend developer
- Industry: Finance
- Enhanced a portal for the bank's KYC process
- Built multiple backend services and PostgreSQL databases using Liquibase and Docker
- Connected several REST interfaces
- Wrote tests and ensured quality
- Deployed services to an OpenShift cluster
- Team: Kanban team with about 5 developers
- Technologies: Java, Maven, JPA, JUnit, Mockito, Git, Docker, Spring Boot, PostgreSQL, OpenShift, Liquibase, OpenAPI, GitLab
Software Engineer
Creditreform e.V.
- Project focus: Backend development for debt collection software
- Client: Creditreform e.V. (in-house)
- Project period: 06.2023 – 08.2023
- Role: Java backend developer
- Industry: Debt collection & credit checks
- Enhanced the in-house backend software used in over 130 branches
- Assisted with data migrations from MongoDB to PostgreSQL
- Refactored code, fixed bugs, and tested
- Improved Scrum process and overall team organization
- Created technical and process documentation
- Team: Scrum team with 5 developers, product owner, tester & Scrum Master
- Technologies: Java, Spring Boot, Maven, JPA, JUnit, Mockito, Jenkins, Kubernetes, Helm, Git, Vault, MongoDB, PostgreSQL, Open Telekom Cloud
Software Engineer
The NextGen GmbH
Software/DevOps Engineer
Senacor Technologies AG
Project focus: Backend development for a test drive booking portal
Client: (confidential)
Project period: 03.2022 – 10.2022
Role: Fullstack developer / DevOps engineer
Industry: Automotive
Enhanced a portal for booking test drives by end customers through dealers
Backend development and testing
Designed and linked REST interfaces between frontend and backend
Maintained Elasticsearch and monitored logs in Kibana
Produced documentation and instructions
Presented results to the client after each sprint
Secured REST interfaces with role-based access and secrets management
Team: Scrum team with about 6 developers and 1 business analyst
Technologies: Java, Maven, JUnit, Mockito, Quarkus, Jenkins, TypeScript, Docker, Kubernetes, AWS, Terraform, Groovy, Event Store, Elasticsearch, Git
Project focus: Backend development for a charging equipment recommendation portal
Client: (confidential)
Project period: 08.2021 – 03.2022
Role: Fullstack developer
Industry: Automotive
Built a portal recommending suitable charging equipment for electric cars
Developed a core algorithm for generating recommendations
Backend development and testing
Designed and linked REST interfaces between frontend and backend
Created architecture diagrams and user guides
Coordinated feature development with the client
Onboarded new team members
Team: Scrum team with about 3 developers and 3 business analysts
Technologies: Java, Maven, JUnit, Mockito, Quarkus, Jenkins, Angular, MSSQL, Docker, AWS, Git
Software Engineer
Blackned GmbH
- Project focus: Backend development for an in-house product
- Client: Blackned (in-house)
- Project period: 03.2021 – 07.2021
- Role: Java developer / network engineer
- Industry: Public safety
- Integrated a network protocol into an existing network stack for an ad-hoc mobile network
- Developed Java sockets
- Extended an interface using Vaadin
- Configured a firewall
- Performed tests and quality assurance
- Team: Solo, with occasional support from senior colleagues
- Technologies: Java, Maven, sockets, JUnit, REST, OSGi, Apache Karaf, Vaadin, Git
Software Engineer
Accenture Technology Solutions GmbH
Project focus: Expanding a development infrastructure
Client: (confidential)
Project period: 09.2020 – 01.2021
Role: Platform engineer
Industry: Transportation
Developed a Kubernetes controller in Go to manage dev projects automatically
Maintained existing components
Planning and documentation
Contributed to the open-source project Crossplane
Team: Scrum team with about 6 developers and architects
Technologies: Go, Docker, Kubernetes, AWS, Git, Crossplane
Project focus: Frontend development for a tax portal
Client: (confidential)
Project period: 02.2020 – 09.2020
Role: Java frontend developer
Industry: Public sector
Enhanced features from requirements documents
Developed frontend screens
Bug fixes, maintenance, and upkeep
Tests and quality assurance
Data analysis
Team: Team with about 10 developers, plus testers and designers
Technologies: Java, Maven, JUnit, Mockito, Jenkins, JSP, SQL, HTML, CSS, Git, GitLab
Project focus: Backend development of a microservice application
Client: (confidential)
Project period: 08.2019 – 01.2020
Role: Java backend developer / DevOps engineer
Industry: Finance
Designed and implemented backend microservices
Connected services to the frontend
Built and maintained a developer pipeline with Jenkins
Set up monitoring with Grafana and Prometheus
Created documentation and onboarded offshore colleagues
Team: Scrum team with about 6 developers
Technologies: Java, Maven, JUnit, Mockito, Spring Boot, Jenkins, REST, OpenShift, Prometheus, Grafana, Git, Bitbucket
Project focus: Backend development of a customer support interface
Client: (confidential)
Project period: 02.2019 – 08.2019
Role: Java backend developer / business analyst
Industry: Telecom
Took over a poorly maintained codebase
Enhanced features
Improved code quality with tests and documentation
Maintained and deployed new builds
Performed requirements analysis and presented results to the client
Replaced the core algorithm for calculating scenarios
Team: Worked with one offshore developer and one business analyst
Technologies: Java, Maven, JUnit, SOAP, MSSQL, Tomcat, Subversion
Project focus: Internal traineeship / jumpstart
Client: Accenture (internal)
Project period: 12.2018 – 01.2019
Role: Java developer
Industry: Consulting
Introduction to corporate culture
Trainings in Java
Trainings in agile working
Trainings in Spring Boot
Earned Java OCA and Professional Scrum Developer I certifications
Team: Group of six participants with rotating trainers
Technologies: Java, Spring Boot, JDBC, JPA, JUnit, Mockito, agile development
Java/Python Developer
Technical University of Munich
- Master’s thesis in a research setting (Electrical Engineering faculty, Chair of Communication Networks)
- Designed a protocol extension for random access in 5G
- Implemented a network simulator in Java
- Ran experiments and collected measurements
- Developed a data analysis tool in Python
- Analyzed data in the tool and created charts
- Wrote a scientific thesis presenting results and conclusions
- Team: Solo, with occasional support from a PhD student
- Technologies: Java, Python
Embedded C/Python Developer
Technical University of Munich
- Interdisciplinary research project (Electrical Engineering faculty, Chair of Communication Networks)
- Attended “Broadband Communication Networks” lectures
- Designed a network protocol for determining network size among microcontrollers
- Implemented the protocol in embedded C in the OpenWSN firmware
- Developed a control client in Python
- Ran experiments and collected measurements
- Processed results for a scientific thesis
- Team: Solo, with occasional support from a PhD student
- Technologies: Embedded C, Python
Network/Linux Engineer
Technical University of Munich
- Lab course: Build your own Internet (Informatics faculty, Chair of Network Architectures and Services)
- Set up networks with PCs and a Cisco router
- Implemented static and dynamic routing
- Implemented security measures like DNSSEC, IPSec, and TLS
- Configured a firewall with iptables
- Set up and secured a Wi-Fi network
- Configured NAT and DHCP
- Performed packet analysis with Wireshark
- Linux shell scripting
- Team: Worked with a fellow student
- Technologies: Linux shell, Wireshark, Cisco router, TCP/UDP
Senior software engineer in backend development, cloud engineering, and DevOps in international environments. I have worked in various sectors including automotive, finance, telecom, and the public sector.
I specialize in custom backend and cloud solutions with a tool-agnostic approach. By using AI tools like ChatGPT, I can quickly develop applications in any backend language, design APIs, and build cloud infrastructures with IaC for all major cloud providers, regardless of prior specific experience.
I also create optimized CI/CD pipelines and design containerized environments for software management and monitoring. With my soft skills and Scrum knowledge, I help improve team efficiency. I like to think outside the box and ensure solutions are not only well developed but also effectively marketed.
Technical University of Munich
MSc Computer Science · Computer Science · Munich, Germany
University of Groningen
BSc Computer Science · Computer Science · Groningen, Netherlands
Certified Open Source Developer for Enterprise
Linux Foundation
Microsoft Certified: Azure Administrator Associate
Microsoft
Aviatrix Certified Engineer Hybrid Cloud Specialty
Aviatrix
Professional Product Discovery and Validation
Scrum.org
Aviatrix Certified Engineer Multicloud Network Professional
Aviatrix
HashiCorp Certified: Terraform Associate 003
HashiCorp
PAL – Evidence-Based Management
Scrum.org
Professional Scrum Facilitation Skills
Scrum.org
Professional Scrum Product Backlog Management Skills
Scrum.org
Professional Scrum with User Experience I
Scrum.org
Scaled Professional Scrum
Scrum.org
Certificate of Cloud Security Knowledge (CCSK v5)
Cloud Security Alliance
Certificate of Competence in Zero Trust (CCZT)
Cloud Security Alliance
Certified Blockchain Architect
Blockchain Council
Certified Blockchain Developer
Blockchain Council
Linux Foundation Certified IT Associate
Linux Foundation
Open Source Licensing Basics for Software Developers (LFC191)
Linux Foundation
OpenTelemetry Certified Associate
Linux Foundation
Google Cloud Certified Associate Data Practitioner
Aviatrix Certified Engineer Multicloud Network Cloud Backbone Specialty
Aviatrix
GitHub Actions
GitHub
GitHub Foundations
GitHub
AWS Certified Machine Learning Engineer Associate
AWS
Aviatrix Certified Engineer Multicloud Network Security Specialty
Aviatrix
Kubernetes and Cloud Native Security Associate
Linux Foundation
AWS Certified AI Practitioner
AWS
Certified AppSec Practitioner
SecOps Group
Certified Blockchain Practitioner
SecOps Group
Certified Cloud Security Practitioner-AWS
SecOps Group
Microsoft 365 Certified: Fundamentals
Microsoft
Microsoft Certified: Security, Compliance, and Identity Fundamentals
Microsoft
AWS Certified Data Engineer Associate
AWS
Certified GitOps Associate
Linux Foundation
Oracle Cloud Data Management Certified Foundations Associate
Oracle
Oracle Cloud Infrastructure AI Certified Foundations Associate
Oracle
Oracle Cloud Infrastructure Generative AI Certified Professional
Oracle
RabbitMQ Training Course
CloudAMQP
Google Cloud Certified Professional Cloud Architect
Professional Agile Leadership I
Scrum.org
Prometheus Certified Associate
Linux Foundation
AWS Certified Security Specialty
AWS
Open Telekom Cloud Architect
T-Systems
Professional Scrum Product Owner I
Scrum.org
Professional Scrum Product Owner II
Scrum.org
Professional Scrum with Kanban I
Scrum.org
Google Cloud Certified Associate Cloud Engineer
AWS Certified Solutions Architect Associate
AWS
Professional Scrum Master I
Scrum.org
Professional Scrum Master II
Scrum.org
AWS Certified Solutions Architect Professional
AWS
Microsoft Certified: Azure AI Fundamentals
Microsoft
Microsoft Certified: Azure Data Fundamentals
Microsoft
Neo4j Certified Professional
Neo4j
Neo4j Graph Data Science Certification
Neo4j
Green Software for Practitioners (LFC131)
Linux Foundation
AWS Certified DevOps Engineer Professional
AWS
Alibaba Cloud Certified Associate
Alibaba
Gremlin Certified Chaos Engineering Practitioner
Gremlin
Oracle Cloud Infrastructure Certified Foundations Associate
Oracle
Tencent Cloud Practitioner
Tencent
Aviatrix Certified Engineer Multicloud Network Associate
Aviatrix
Aviatrix Certified Engineer Multicloud Network Automation Specialty
Aviatrix
IBM z/OS Mainframe Practitioner
IBM - Coursera
Salesforce Certified Associate
Salesforce
Certified Jenkins Engineer
CloudBees
Complete Ethical Hacking Bootcamp
Zero to Mastery – Udemy
Kubernetes and Cloud Native Associate
Linux Foundation
AWS Certified SysOps Administrator Associate
AWS
Google Cloud Certified Cloud Digital Leader
Docker Certified Associate
Mirantis
Microsoft Certified: Azure Fundamentals
Microsoft
AWS Certified Developer Associate
AWS
Design Thinking
SAP
Successful Communication Training
Accenture
AWS Certified Cloud Practitioner
AWS
Dynamic Leadership Training
Accenture
Technology Architect Associate
Accenture
Lateral Leadership Training
Accenture
Java 8-14 Training
Accenture
Oracle Certified Associate Java 8
Oracle
Professional Scrum Developer I
Scrum.org
Sommerschule Liberalismus
Telders Stiftung
Agile Software Engineering
Andrena Objects
B
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