Management Team

Bart Heilbron
Co- founder & Chief Executive Officer
Bart’s entrepreneurship and firm belief in the power of online engagement inspired him to co-found GX Software in the early days of the World Wide Web. As head of sales and business development operations for many years, he managed the company’s growth with his strategic insights into the online market. The organization’s success led to the expansion of Bart’s role and today he is CEO of GX Software. With his leadership, the company has become a highly successful provider of online marketing software while maintaining its vision for a strong future. Bart is passionate about cross-channel, customer-driven online engagement and holds a master’s degree in communication and new media.

Martijn van Berkum
Co-founder & Chief Technology Officer
Martijn brings to GX Software a tremendous amount of experience and innovation in product management and business development, with an expert ability to integrate technology, the Internet and marketing. He has a passion for cutting-edge technology and its impact on markets, business and society. Martijn is a true visionary, driving the company’s thought leadership. In collaboration with R&D and marketing, he translates his vision into world-class GX Software products.

Hans Willems
Chief Marketing Officer
Hans brings more than 20 years of B2B marketing and business development experience to his role as CMO for GX Software. Since joining the company in 2007, Hans has managed internationalization and corporate marketing strategies, delivering standard internet solutions for online marketers, content and e-business managers. Previously, Hans worked at Niku Corporation, contributing to the successful introduction of European Niku operations, and at the Baan Corporation, where he was responsible for the European sales operations solution center.

Harmen W. Haarman
Chief Financial Officer
Harmen holds a degree as Executive Master of Accounting and has a wide-ranging background in financial services and in the technical industry. In his previous job, as a Financial Manager for Apple (Nasdaq: AAPL), he contributed to Apple’s continuing expansion in Europe. As Chief Financial Officer, he is responsible for all corporate accounting, controlling, tax and finance activities.

EJ Melzer
Senior Vice President North America
EJ is a seasoned, results-driven executive. He has successfully built top-performing sales and delivery organizations for fast-growing software organizations. Before joining GX Software, he held senior business development and client management positions for pre- and post- IPO software companies in the US and Europe. He leads the North America organization for GX Software.

Frans Verstraten
Vice President International Partner Operations
Frans is responsible for building and expanding GX Software’s worldwide partner footprint. He has more than 20 years’ experience in the IT industry, working for organizations such as Oracle, PeopleSoft and Baan. Frans has held several senior positions in sales, project management,channel and SI-alliances management in the Netherlands, Belgium and Germany. In these positions, he acquired senior expertise building international businesses in the fields of CRM, MDM, BI, WCM and CEM solutions.

Willem Rossieau
Vice President Sales Europe
Willem has over 10 years of working experience at GX Software now and was responsible for all Sales in Benelux. Being an early stage employee and a well-respected member of the Management Team, Willem is one of the key contributors for the company. He has built successful sales teams, created relationships on the enterprise level and managed European sales expansion. In his current position Willem is responsible for all sales activities in Europe.