Gustav Lotz

Working onTravelstartKiyoh / KlantenVertellenMargus

PreviouslyCFOHIRETelematicsAI

Most of my work starts with a system that has become hard to change: an AngularJS app nobody wants to touch, business rules buried in spreadsheet formulas, a single-brand site that suddenly needs to serve many brands. I work out what the existing system actually does, then move it onto something teams can keep building on. The details are in my case studies.

I also write about what I learn along the way: migrations, multi-tenant architecture, payments, testing and the guardrails that keep a codebase healthy. A few favourites are One Codebase, Any Number of Brands, Skipping 10 Years of Frontend and Rebuilding Margus. The rest are on the writing page.

If you want the longer version, there's more about me and where I've worked.

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Have a system that needs modernising, or a product that needs senior engineering? Mail me at lotzgustav@gmail.com.