Gerben C. Th. Wierda M.Sc. MBA (1961) works as enterprise architect (current role: lead architect SIS) for APG, which manages approximately 500 Billion Euro in assets for roughly 5 million participants in a number of Dutch collective pension funds. Before that he was (amongst other things) Lead Architect of the Judiciary in The Netherlands, and Head of the forensic IT department of the Dutch Forensic Institute.
In his spare time he is an independent author of blogs (of which the central one is https://ea.rna.nl/) and books, based on real world experiences in complex enterprises (of himself or his network) and (very occasionally) provides consultancy, training/coaching. His books are Mastering ArchiMate (now in its third edition) and Chess and the Art of Enterprise Architecture.