I'm Pieter Leek
Industrial Systems Architect | OT/IT Integration & Custom Middleware
I quickly see how a system works, where the data stops flowing, and what needs to happen — whether you're in crisis or want to stay out of one.
OT/IT Systems • Custom Middleware • System Integration • On-Site Worldwide
Technical Services
Hands-on technical expertise at the intersection of OT and IT — on-site, worldwide.
OT & IT — One System
Your IT department and your people on the floor speak a different language. I understand both sides and make sure the technology and the communication align. I can design the architecture and then go on-site to make it work. I don't hand off to someone else when it gets technical.
Custom Middleware & Connectors
Your machines and systems don't talk to each other — or to anything above them. I build the software layer that connects them: protocol translators, edge data services, API wrappers, and message pipelines. Whether it's MODBUS, OPC-UA, MQTT, or a proprietary interface — I make it flow.
System Integration
Your data is stuck on the machine. I make sure it gets where you need it — historian, dashboard, MES, ERP, or cloud — using OPC-UA, MQTT, Ignition, or custom connectors built for your specific situation.
Troubleshooting
Something is not working and nobody knows why. I find out, and I fix it — during commissioning, in production, or anywhere in between.
Go-Live Support
Go-live coming up and not enough hands on deck? I step in as an experienced technical resource — on-site, up to speed quickly, and ready to work across the full stack.
Python
JavaScript
AWS
Azure
CCNA
IoT
Linux
About
OT and IT are not two separate worlds to me. They are one system that needs to work together.
That means I can move across the full stack: from sensors and industrial networks to software architecture and cloud connectivity. I don't get lost when a problem crosses a boundary, because I know what's on both sides.
I work with end users who need a problem solved fast, and with machine builders and system integrators who need someone experienced on-site when their own team is not enough.
I don't need a long ramp-up. I can read a system, find the weak point, and act — whether that's in the network, the software layer, the integration, or somewhere in between.
Reference Work
Building a Connected Industrial System
To validate how I think about industrial integration, I designed and built a working reference implementation of a connected OT/IT stack — from field sensors to cloud, following ISA-95 data modeling and IEC 62443 zone structure.
This is not a simulation. ESP32 sensors publish over MQTT with certificate-based identity, a hardened broker handles routing, an ISA-95 namespace enforces data structure, and Ignition SCADA consumes and visualizes the result. All containerized, version-pinned, and declaratively managed in Git.
A six-part video series is in production, documenting each integration layer under real conditions.
Contact
Need someone who knows both sides? Mail me at pieter@qman.io or send a message on LinkedIn.
From wiring to code, and everything in between.