Legal notice (Impressum)

About sumthink

sumthink is a venture studio, IP factory and open builders' collective from Hamburg. We design and build digital products for clients and our own ventures, from specification to code.

For project requests, please use the form on the homepage or book a 15-minute fit call.

Our services at a glance: the UX design subscription, fixed-price expert reviews for code, architecture and specifications, and studio projects from idea to market entry.

If you spot an error on this website, please let us know at info@die-quadratur.de. We will correct it promptly.

sumthink combines three things under one brand: a venture studio that develops digital products with clients and partners, an IP factory for our own products such as Aimber, signeee and wearner, and an open collective of experts who build together and challenge each other.

We work remotely from Hamburg across Germany and the EU. On-site meetings are possible by arrangement.

We call our stance Actual Intelligence: we use AI where it makes a product better and let people decide where judgment matters.

Quick answers

Who is behind sumthink?

Christian Durlej, founder and managing director of Die Quadratur UG, together with a collective of named experts.

Where is sumthink based?

In Hamburg, at Sierichstraße 120.

What is the fastest way to reach sumthink?

Through the request form on the homepage or a 15-minute fit call. You get an answer within one working day.

Where do press and partnership requests go?

Also to info@die-quadratur.de.