GERMANY: Cologne-based Sidestream joins the Ardelin group to expand software engineering capabilities and market reach

From Left to Right: Nils Jonalik, Co-Founder and MD of Sidestream, Dr. Marek Jersak, CEO of Ardelin and Daniel Kremerov, Co-Founder and MD of Sidestream

From left to right: Nils Jonalik and Daniel Kremerov

Ardelin company logo

Deal extends Ardelin’s custom software-development expertise for business-critical applications, AI-enabled software innovation and secure digital services

Sidestream is an outstanding addition to Ardelin. Its engineering excellence, entrepreneurial culture and deep technical expertise perfectly complement the capabilities already within our group.”

— Dr. Marek Jersak

COLOGNE, GERMANY, August 19, 2026 /EINPresswire.com/ -- Cologne-based software engineering company Sidestream is joining Ardelin, strengthening the end-to-end software solution expertise and delivery capabilities available to organisations operating and innovating business-critical applications.

Founded in 2019, Sidestream has built a

strong reputation for designing and developing bespoke software for organisations where reliability, security and long-term performance are essential. Its projects span inventory, order and workflow management solutions, digital solutions for regulated processes, security-focused financial technology and public-health applications for the City of Cologne.

Dr. Marek Jersak, CEO of Ardelin, said: "Our vision is to build a leading European group of software, data and AI services and solutions companies, bringing together complementary expertise, market reach and scale, enabling our customers to solve their most demanding, business-critical digital challenges.
“Sidestream is an outstanding addition to Ardelin. Its engineering excellence, entrepreneurial culture and deep technical expertise perfectly complement the capabilities already within our group.

“As organisations modernise critical business processes and embrace AI, they need solutions partners with intimate industry understanding, specialist knowledge, end-to-end delivery capability and scale to create value faster and innovate with confidence. Together, we are strengthening our joint ability to focus on the most impactful customer needs and deliver exactly that."

Nils Jonalik, Co-Founder and MD of Sidestream, said: "Sidestream has always believed that the best software starts with understanding the customer's operational challenges. We’ve built our business by developing secure, scalable solutions that deliver long-term value rather than short-term fixes.

Daniel Kremerov, Co-Founder and MD of Sidestream, added: "Joining Ardelin allows us to continue doing what we do best while becoming part of a wider group of specialist technology businesses that share our values, engineering culture and long-term commitment to customers. Our clients will benefit from broader expertise while continuing to work with the same people they already know and trust."

Sidestream will continue to operate from Cologne under its existing leadership team as part of the Ardelin group, ensuring continuity for customers while expanding access to the group's broader expertise and delivery capability across software engineering, data, cloud, AI and digital transformation.

The addition represents another step in Ardelin's ambition to build Europe's leading group of specialist digital services businesses, bringing together complementary capabilities to help customers modernise critical operations, introduce AI effectively and efficiently, strengthen software security and accelerate the creation of long-term business value.