Léon Hagenaars-Keus

Senior Software Engineer & Architect

Profile

I am a driven Senior Software Engineer, Architect, and Coach with a passion for the full code lifecycle. My focus lies on:

• Software Architecture & DDD: Translating complex domains into robust, scalable, and team-enabling architecture.
• AI in Software Engineering: Research and development of AI-tool-agnostic agents, local LLMs, and AI skills.
• Automation (CI/CD): Optimizing the software delivery process and developer experience.
• Coaching & Mentoring: Guiding engineers and providing specialized CI/CD training to elevate teams.

Work Experience & Projects

Sogyo internal (De Bilt) – Researcher & Senior Software Engineer

10-2025 – Present

• Research into software development using various AI tools, focused on harnessing, local LLMs, DGX clustering, and building AI-tool-agnostic harnesses, agents, and skills.

OllamaVllmJetBrains JunieGitHub CopilotZooCode/RooCodeClineClaude.ai

KPN (Rotterdam) – CI/CD Expert & Senior Software Engineer (via Sogyo)

10-2025 – Present

• Supporting the transition to an OpenShift/Kubernetes-based architecture in preparation for 6G.
• Setting up GitLab CI infrastructure and coaching on industry standards and best practices.
• Teaching IaC and CI/CD concepts; conducting workshops and knowledge sharing around backward chaining, Git, and CI in general.

HelmGitLab CIGitHub ActionsArgo-CDIaCCI/CDBackward Chaining

ING (Amsterdam) – Senior Software Engineer & Coach (via Sogyo)

03-2021 – 09-2025

• Development of Intent-based firewalling and modeling the domain for internal infrastructure chargeback.
• Coaching and training an infrastructure team in Object-Oriented Design and DDD to evolve into a full-fledged development team.
• Setting up robust build infrastructure for the team.

Azure DevOpsGoLangKotlinAKSHelmAnsibleCucumberBackward ChainingEvent StormingDDDOOKnowledge Elicitation

Sogyo internal (De Bilt) – Senior Software Engineer, Platform Engineer, DevOps Engineer & Teacher

06-2013 – Present

• Setting up and managing internal cloud-native infrastructure, build pipelines, and hosting environments for development teams.
• Training and mentoring junior and medior software engineers within Sogyo.
• Further development and refactoring of an event-sourced HR and trainee tracking application.
• Setting up an internal AKS cluster for the HR application and build infrastructure for internal projects.

KubernetesAKSDockerGitLab CIAnsibleTerraformHelmELK-stackC#Event Driven ArchitectureDevOpsEvent StormingCI/CD

Shorter Advisory & Engineering Assignments: ASR & Videns IT (via Sogyo)

01-2021 – 12-2021

• ASR: Supporting and coaching Chapters and Guilds for more effective collaboration; coaching and teaching CI/CD and TDD; contributing to the software engineering vision. Azure DevOpsSpecFlowCI/CDTDD
• Videns IT: Setting up CI/CD stack with GitHub Actions & Docker; refactoring and making SDN monitoring software testable; coaching a junior in applying OO/DDD in Python, basic architecture skills, refactoring, and clean coding. PythonDjangoReactJSOODDDClean Code

Norma Foundation (De Bilt) – Software Engineer (via Sogyo)

11-2015 – 04-2021

• Implementation of an event-sourced actor model to apply private copying levy budget distribution rules.

Akka.netOctopus.NET 4.5Azure VM'sWebAPIWPFSpecFlow.NET Core / .NET 5

Various Assignments as Software Engineer & Architect (via Sogyo)

01-2009 – 12-2014

• Executed diverse projects for clients including Vodafone, Micro Valley, Solviteers, and Mindz.com.
• Focus on designing scalable architectures (Domain Driven Design, Event Sourcing), introducing Continuous Delivery (Jenkins), and coaching development teams.

C#.NET (3.5/4.0/4.5)ASP.NET MVCWCFTDDScrumAgileEvent StormingBackward Chaining

Earlier Employers: Voice Data Bridge & Remotion

09-2002 – 12-2008

• Voice Data Bridge (2007 – 2008): As Software Engineer, responsible for the development of directory assistance services and call center applications.
• Remotion (2002 – 2007): As ASP Web Developer, responsible for the technical implementation of CMS projects, intranet backends, and reservation systems.

Education

• Systems And Control – TU Delft (DCSC), Delft (01-09-2003 – 01-04-2007)
• Electrical Engineering – TU Delft, Delft (01-09-1996 – 01-04-2007) Propedeuse (first-year certificate) completed
• VWO – Stanislas College, Delft (01-09-1989 – 01-07-1996) Completed

Certifications

• Microsoft TS: Microsoft .NET Framework 3.5 – Windows Communication Foundation
• Microsoft TS: Microsoft .NET Framework 2.0 – Web-Based Client Development
• Microsoft TS: Microsoft .NET Framework 2.0 – Application Development Foundations
• EXIN: Foundation Certificate in Object Orientation