Senior Java/Kotlin Engineer, 25+ years of experience, specialising in Java and Kotlin programming, cloud-native architecture, DevOps. Extensive expertise in Java-to-Kotlin migration, scalable Kafka- and Quarkus-based systems, CI/CD and production monitoring. Available remotely or on-site (periodic).
Track record includes leading Java-to-Kotlin migrations (Bol.com, NVWA, Veldsink Groep), building and operating Kafka- and Quarkus-based microservices at scale (Alliander, TenneT TSO), and delivering full-stack solutions combining Java/Kotlin backends with Angular frontends (SNS Bank, NVWA). Comfortable owning the full delivery lifecycle: domain-driven design, CI/CD (Jenkins, GitHub Actions, ArgoCD, Tekton), containerization (Docker, Kubernetes), and production monitoring (Splunk, ElasticSearch, OpenTelemetry). Recent experience also includes Python/AI tooling (PyTorch, LangChain4J) alongside core Java/Kotlin work.
Experience
Professional experience10+ years
Freelancer since2013
Languages
EnglishFluentDutchNative speaker
Project history
Senior Java Engineer
Alphabet/BMW, Breda
Automotive & Vehicle Manufacturing
>10.000 team member
Migration of Python/Java application to AI-based solution; removal of CodeQL/GitHub vulnerabilities.
Java lead in Angular/Java team; version migration to Kotlin, development of Angular barcode scanner, raising team’s Java/Kotlin proficiency (preventing Jotlin anti-patterns).
Migration of PHP applications to Java; leading junior and senior team members. Analysis of AI application (Keras) and cloud hosting platforms (GWS, AWS, Azure Container Apps), reporting dashboards, integration/performance/security testing.
Core team member in SAFe/ART environment; working on multiple Quarkus applications within Equality, a large central system for managing the electricity grid.
Scrum team member during transition phase; onboarding of developers from India, 24/7 third-line production support (keeping trains running), active sprint backlog development.
Java lead (Scrum, 4 people); Vattenfall Trading Platform (VHP/VTP) B2B energy trading application. Took over codebase from two departing developers, automated previously manual procedures, established Scrum ceremonies and Way of Working.
Semi-lead in Kanban team; internal/external web application. Migrations: Java 8 to 11, SVN to Git, Kanban to Scrum; modernisation of legacy code, Splunk Enterprise dashboards.
Greenfield design, development and architecture of cooperating microservices separated by Kafka topics (DDD). CI/CD via GitOps webhooks with Tekton/ArgoCD, deployment on OpenShift/AWS. Unique: direct control of field equipment via Kafka from software. Splunk reporting dashboards.
Technical designer/architect in SAP team (9 people). Greenfield domain model (DDD) and SOA middleware between SAPUI5 frontend and ABAP ODataV2 backend; Java services BIG and DPG using SAP CAP Java/CDS4J; custom Spring extension ‘CEP’ (CAP Extension Programme). CQRS preparation, presentations in organisational guilds.
Technologies: Java 11, Maven, SAP CAP Java, CDS CLI, Spring Boot, SAP UI5, SAP Cloud Foundry/CF CLI, SAP HANA DB, MTA, Olingo, OData V2/V4, XSUAA, NodeJS, Docker, PostgreSQL, GitHub Actions, SonarQube/SonarCloud, JMeter, Postman, PlantUML, Eclipse
Senior Java Developer
Dutch Tax Authority
Government and Public Services
>10.000 team member
Developer on IBS VAT Foreign (Omzetbelasting Buitenlands); applications ESS and LEO. Frontend/backend, SAFe, advocate for proper Scrum practices and Wiki/Confluence, proposals for Java development pipeline (Java-Ontwikkelstraat).
Developer and interim Scrum Master; application SEA. Frontend/backend, SAFe, Community of Practice Quality, integrating SIG measurements/ISO 25010 into the build process.
