Agentic coding for .NET teams | Chaïm Zonnenberg

Sound familiar?

Your developers are experimenting with GitHub Copilot, Claude Code and Cursor. It isn't making a measurable difference yet. The output stays the same, only the tooling changed.

Your backlog is growing, your velocity isn't. AI generates more code and review pressure grows with it. It feels like the tooling changes while the way you work stays put.

You're not looking for a course or workshop. You're looking for someone who joins your sprint and shows how it's done.

Schedule an introduction

I'm Chaïm Zonnenberg. 20+ years in .NET, 2x cum laude university degree. I build Invullen.nl entirely with Claude Code and use it daily for maintaining Factuur-Assist.nl (135+ customers). This is daily practice, not theory. As a standalone service for teams it's newer, which is why I start small and testable. I want to bring that workflow to your team, 2 days a week.

More about me

APPROACH

How I speed up your .NET team

No workshop, but building alongside and demonstrating.

Agentic coding

I help your .NET team make agentic coding work: AI agents generate production code, you stay in control. With Claude Code, GitHub Copilot or a multi-provider setup, whatever fits your team. The goal: as we ship features together, your team takes over the workflow and works faster and with more confidence.

See the approach

Track record

Daily with Claude Code, since August 2025

on two own SaaS products in production

20+ years of .NET experience and an enterprise security/SSO background

Microsoft Certified AI-103

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Where I come from

Identity & SSO

Implementing enterprise SSO was my work long before I focused on agentic coding, and I'm still asked for it regularly. Is an enterprise deal stuck on a security review or an SSO requirement? I build SSO and SCIM into your .NET SaaS so you get through it, without your team having to become identity experts.

How we work together

From experimenting to agentic coding in three steps

I watch first

Together we map the concerns that live in the team and the technical challenges in your codebase. We only take first steps once the risks, objections and preconditions are clear and shared across the whole team, with real buy-in. Nothing gets rolled out over the team's head.

We ship together

Two days a week in your sprint. In the first week we work on a real feature or improvement in your own codebase, not a standalone demo. From there we iterate and refine the way of working as we keep building.

Your team runs it without me

The context files, agent instructions and review agreements then live in your normal way of working. I make myself redundant, and that's the whole point.

Read the full approach

Experience & references

20+ years at ABN AMRO, PGGM, Van Lanschot & more 2x cum laude university Microsoft Certified: Azure AI Apps & Agents & Identity & Access

Complex migration project delivered successfully

"Chaïm managed a large and complex migration project for us and brought it to a successful conclusion. He got up to speed exceptionally fast and consistently made the right decisions based on his deep knowledge of .NET and SQL Server."

Cees

Software Architect at multinational

Proactive from day one

"Chaïm is a true professional. One you don't want to let go from day one. Proactive is his motto. He picks up what matters and doesn't let go until it's resolved."

Robert

IT Team Lead at financial institution

Advised the board on architecture

"Chaïm filled the advisory role of Software Architect at our organization. He advised the board and gave direction to the software architecture. He also guided the development team into the world of microservices and brought knowledge about Microsoft Azure."

Chantal

IT Operations Director

Previous clients

Own SaaS products

Factuur-Assist.nl 135+ customers

Invoicing app for freelancers and small businesses. Simple and fast invoicing.

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Invullen.nl Pilot 2026

Exploratory questionnaires for coaches and trainers. Know where your participants stand before the session.

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Frequently asked questions

What is agentic coding?

Agentic coding means building software with AI agents that work autonomously in your codebase: generating code, running tests, refactoring. With tools like Claude Code, GitHub Copilot and Cursor. You specify, review and steer; the agent does the work.

Which teams do you work with?

.NET teams that already experiment with AI tooling and don't see a real speed-up yet. From scale-up to enterprise.

Do you work on-site or remote?

Both. Mostly on-site, some remote. I'm based in the Utrecht area and take on engagements within about an hour's travel.

How quickly do I see results?

Within the first week I ship a feature with Claude Code in your codebase, so your team sees agentic coding work live.

All frequently asked questions

Chaïm Zonnenberg

.NET Developer | 20+ years

From September: room for 1-2 teams

Email

info@software-assist.nl

Phone

+31 6 51914406

linkedin.com/in/chaimzonnenberg

Location

Based in the Utrecht area, The Netherlands. Available for on-site and remote work.

Schedule an introduction Know today if I'm the right fit LinkedIn

View frequently asked questions

More code, more review.
Not shipping faster yet?

Sound familiar?