About Attesso B.V.

Attesso is a Dutch software company building the PSP-agnostic authorization layer for agentic commerce: every agent action is checked against customer-approved limits, and returned with signed evidence anyone can verify. It was founded by Douwe Kramer and Sid van Kalken.

Attesso exists to make autonomy trustworthy. Every action an agent takes should trace back to a person who allowed it, in terms anyone can verify. That is the layer we build.

Agent-led workflows are often asynchronous: inventory and prices can change after a customer leaves. Repeating a manual approval can make a valid offer disappear, while a broad approval makes it difficult to prove what the customer actually authorized.

A mandate is the customer-approved boundary for a later action. Attesso lets a platform create an immutable, time-bounded mandate and present it for passkey approval. The platform then submits a concrete proposed action. Attesso evaluates it against that mandate and returns a deterministic decision with signed evidence; the platform remains in control of execution.

Native Attesso remains fully usable without AP2. Attesso is exploring an AP2 v0.2 human-not-present adapter as a future compatibility option, with Attesso as the Verifier, not the Merchant or payment-method provider.

The founders

Douwe Kramer

Takes ideas from zero to v1 and iterates fast; designs and builds Attesso’s authorization and evidence platform.

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Sid van Kalken

European Studies student focused on international business and AI; works on Attesso’s commercial development.

LinkedIn

The company

Attesso B.V. is registered in ’s-Hertogenbosch, the Netherlands, under Chamber of Commerce number 42040136. We work with product, engineering, risk, and compliance teams validating one asynchronous action and its existing execution rail.