A field method
Build for the Margins
Paul Mandele
The Book · Out 2026

Constraint is the engine of innovation, not its obstacle.

A decade of building ventures for patchy connectivity, low trust, and irregular income, turned into a method other builders can use. Not a slide deck. A field manual.

288 pages·Ebook, paperback & audiobook·3 chapters free

What a decade of building actually taught me, written down so you don’t have to learn it the expensive way.

Who it's for

Founders, corporate innovators, investors, and DFIs building into Africa and other resource-constrained markets, and anyone tired of playbooks written for conditions they'll never operate in.

What you'll take away

A repeatable method for turning constraint into design input, a trust-first go-to-market model, and the rolling roadmap that replaces the 18-month plan that never survives contact.

How it's built

Twelve chapters, each anchored to a named case study, from a $100K farmer-traceability contract to a hub that produced 40+ startups. Field notes, not frameworks.

Contents

Twelve chapters. Three are free.

Read the first two and the pivotal chapter on trust, in your browser, no email required.

03Designing for the dying batteryLocked
04Offline-first as a default, not a featureLocked
06–12Cash and the trust ladder · Referral at scale · The rolling roadmap · Field research, not focus groups · Putting a team on the ground · From operator to advisor · What compoundsIn the book
Reading — Free PreviewChapter 1 of 3 free
Chapter One

The margin is the market

The first venture I built failed in a way I didn't have language for. The product worked. The demo landed. The pilot funding came through. And then, in the field, nothing moved.

I spent months looking for the bug. There wasn't one. The bug was in my assumptions. I had built for a user who had reliable power, a data plan she didn't have to think about, and a reason to trust a stranger's app with her livelihood. None of those users existed in the market I was actually selling to.

What I learned, slowly and at my own expense, is that the constraints I kept apologising for were not obstacles to the product. They were its real specification. The patchy connection, the shared phone, the fifteen-shilling data top-up, the rational distrust of institutions that had failed before: these were not edge cases to handle later. They were the centre of the brief.

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Ebook$24

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288 pages, matte cover. Ships worldwide. Bundled with the ebook at no extra cost.

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Audiobook$28

7h 40m, read by the author. The case studies, in the voice of the person who lived them.

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