
Glanvet Barretto
MSc
speaks: English, Hindi, Marathi, German
convex ZT GmbH, Graz
Structural engineer

Tanja Bauer
speaks: Deutsch, Englisch
convex ZT GmbH, Graz
Civil engineer

Srdjana Borkovic
MSc
speaks: Serbian, German, English
convex ZT GmbH, Graz
Architect

Ana-Maria Caballo
MSc
speaks: Spanish, German, English
convex ZT GmbH, Graz
Engineer

Lukas Cernosta
Dipl.-Ing.
speaks: Czech, English
Lukas Cernosta e.U., Bříza
Civil engineer

Ilker Demir
Dipl.-Ing.
speaks: Turkish, German, English
convex ZT GmbH, Wien
Civil engineer

Anes Dzinic
speaks: German, Bosnian, English
convex ZT GmbH, Graz
Civil engineer
responsible for 3D-print and drone flight

Julian Ebeling
speaks: German, English
convex ZT GmbH, Graz
Civil engineer

Konrad Edegger
Dipl.-Ing. (FH)
speaks: German, English
convex ZT GmbH, Graz
Division Manager special issues
responsible for training and education
Konrad Edegger studied construction design and management at the FH Joanneum Graz. He is division manager for special issues since 2016.

Madjid Fazeli
Dipl.-Ing.
speaks: Persian, German
Madjid Fazeli e.U., Graz
Civil engineer
Madjid Fazeli studied civil engineering at the Graz University of Technology. He is co-founder of the engineering practice Fazeli-Wolfesberger Ingenieure GesBR. Madjid Fazeli joined convex ZT GmbH working self-employed in 2014.

Tom Friedner
speaks: Hebrew, German, English
convex ZT GmbH, Graz
Civil engineer
starting with 02.2024 on educational leave for 12 months

Salman Gandarov
BSc
speaks: Spanish, Adyghe, Russian, English
convex ZT GmbH, Graz
Civil engineer

Robert Gaspar
Ing.
speaks: German, English
convex ZT GmbH, Graz
Civil engineer

Murat Gökçe
Dipl.-Ing.
speaks: Turkish, German, English
convex Ltd. Şti., Istanbul
Managing Director
Murat Gökçe studied civil engineering at the Istanbul University of Technology and in the following, at the Vienna University of Technology. After fifteen years of management experience in various international companies, he joined the convex group in 2006 as founding partner of convex Ltd. Şti.

Sandra Heiligenbrunner
Dipl.-Ing.
speaks: German, English
convex ZT GmbH
Authorised officer
Division Manager building construction
responsible for Human Ressources
Sandra Heiligenbrunner completed an apprenticeship in technical drafting, and studied civil engineering at the FH Campus Vienna and after that at the FH Joanneum Graz. She is division manager for building construction since 2016 and authorised officer since 2017.

Thomas Heinz
Ing.
speaks: German, English
Stahlbauplanung Heinz, Kreuzlingen
Civil engineer

Anita Hiden
speaks: German, English
convex ZT GmbH, Graz
Office Management

Andrea Hofer
Dipl.-Ing.
speaks: German, English
convex ZT GmbH, Graz
Architect

Viktoria Hofer
Ing.
speaks: German, English
convex ZT GmbH, Graz
Engineer
responsible for team- and project photography

(Čeština) Ondřej Horák
Dipl.-Ing.
Jazyky: Czech, English
convex consult s.r.o., Bříza
Structural engineer

Marina-Edvina Iosu
Dipl.-Ing.
speaks: Romanian, English
convex consulting engineers s.r.l., Cluj-Napoca
Engineer

Muhannad Kassem
BSc
speaks: Arabic, German, English
convex ZT GmbH, Graz
Civil engineer

Emrah Kemaloglu
Dipl.-Ing.
speaks: Turkish, German, English
Emrah Cagatay Kemaloglu e.U., Wien
Civil engineer

Başak Keser
MSc in Environmental Engineering
speaks: Turkish, English
convex Ltd. Şti., Istanbul
Senior specialist sales & business development

Martina Klinger
speaks: German
convex ZT GmbH, Graz
Office Management

Juraj Kmet'ko
Ing.
speaks: Slovakian, English
convex ZT GmbH, Bratislava
Engineer

Sucheta Kolhatkar
Technician
speaks: Marathi, Hindi, Japanese, English, German
convex ZT GmbH, Graz
Civil engineer

Natalie Kraxner
Ing.
speaks: German, English
convex ZT GmbH, Graz
Project Manager
currently on parental leave

Claudia Lackner
Ing.
speaks: German, English
convex ZT GmbH, Graz
Engineer

Thomas Laggner
Dipl.-Ing. Dr.techn.
speaks: German, English
convex ZT GmbH, Graz
Managing Director
Thomas Laggner studied civil engineering at the Graz University of Technology, and made halso is PhD there. Thomas Laggner is teaching Reinforced Concrete Construction at the FH Joanneum Graz since 2022. He is division manager since 2023 and managing director since 2024.

Juergen Lohmann
Ing.
speaks: German, English
convex ZT GmbH, Graz
Division Manager construction design
responsible for IT
Jürgen Lohmann graduated from the HTBLA Ortweinplatz in Graz. He is division manager for construction design since 2016.

Liebhard Mattuschka
MSc
speaks: German, English
clone:it GmbH, Graz
Civil engineer

Ana Muzic
MSc
speaks: Croatian, English, Italian, German
convex ZT GmbH, Graz
Division Manager structural engineering
Ana Muzic studied civil engineering at the University of Rijeka, Croatia and at the Graz University of Technology, Austria. She is division manager for structural engineering at convex ZT GmbH since 2023.

Wolfgang Nesitka ✝
FH-Prof. Dipl.-Ing. Dr.techn.
Legally certified expert
speaks: German, English
convex ZT GmbH, Graz
Consultant
Wolfgang Nesitka studied civil engineering at the Graz University of Technology, and made his PhD at the same institution. He was Technical Director at the construction Company Ed. Ast & Co. in Graz, and in the following, Head of the Study Course "Construction Design and Economics" at the FH Joanneum University of Applied Sciences in Graz. He is founding partner of convex ZT GmbH. Wolfgang transferred his shares in convex ZT GmbH to Thomas Laggner in 2024 due to age reasons. He is still at the disposal of convex ZT GmbH as a consultant and expert.

Erwin Neumeyer
Ing.
speaks: German, English
Erwin Neumeyer, Gloggnitz
Site Superviser

Armend Nura
Dipl.-Ing.
speaks: German, English, Albanian
convex ZT GmbH, Graz
Structural engineer

Rajashree Omprakash
MSc
speaks: Hindi, German, English
convex ZT GmbH, Graz
Civil engineer
currently on parental leave

Ilayda Özköse
speaks: Turkish, English
convex Ltd. Şti., Istanbul
Office Manager

Roland Paier
Dipl.-Ing.
speaks: German, English
DIROPA IT GmbH
IT Manager
Roland Paier studied Business Informatics and is Microsoft Partner (Datacenter and Midmarket Solution Provider). Since 2004 he has been in charge of the IT infrastructure of convex ZT GmbH.

Yahya Saral
Dipl.-Ing.
speaks: Turkish, English
convex Ltd. Şti., Istanbul
Survey engineer

Jakob Schadner
BSc
speaks: German, English
convex ZT GmbH, Graz
Architect

Marinko Sekulic
Ing.
speaks: German, Bosnian, English
HE house of engineering OG, Graz
Electrical engineer

Murat Sezer
Technician
speaks: Turkish, English
convex Ltd. Şti., Istanbul
Site supervisor

Süleyman Sezer
Dipl.-Ing.
speaks: Turkisch, English
convex Ltd. Şti., Istanbul
Civil engineer

Izudin Sisic
Ing., BSc
speaks: Bosnian, German, English
convex ZT GmbH, Graz
Division Manager BIM
responsible for VR- and AR-applications
Izudin Sisic studied civil engineering at the Graz University of Technology, Austria. He is division manager for BIM at convex ZT GmbH since 2023.

Pontus Skoog
MSc
speaks: Swedish, German, English
Skoog e.U., Graz
Mechanical engineer

Bernd Spatzenegger
Dipl.-Ing.
speaks: German, English
p-m-consult e.U., Purkersdorf
Mechanical engineer

Roland Stickler
Dipl.-Ing.
speaks: German, English
convex ZT GmbH, Vienna
Contract manager

Ugur Sümengen
Dipl.-Ing.
speaks: Turkish, English
SCI Mühendislik, Istanbul
Civil engineer

Tacettin Sümer
Dipl.-Ing.
speaks: Turkish, English
convex Ltd. Şti., Istanbul
Civil engineer

Tassilo Szyszkowitz
Dipl.-Ing. Dr.techn.
speaks: German, English
convex ZT GmbH, Graz
Partner
Tassilo Szyszkowitz studied civil engineering at the Graz University of Technology, and made his PhD at the same institution. He co-founded the engineering practice Graber-Szyszkowitz ZT GmbH 1981 in Graz, Austria. Since 2006, he is partner of convex ZT GmbH.

Jennifer Thorer
speaks: German, English
convex ZT GmbH, Graz
Engineer
currently on parental leave

Fabian Till
Dipl.-Ing.
speaks: German, English
convex ZT GmbH, Graz
Civil engineer
responsable for 360° photography

Elisabeth Uhl
Ing.
speaks: German, English
convex ZT GmbH, Graz
Engineer

Timur Uzunoglu
Dipl.-Ing. Dr.techn. MICE CEng
speaks: German, Turkish, English, French
convex ZT GmbH, Graz
Managing Director
responsible for quality assurance
convex consulting engineers s.r.l., Bucharest
Director
Timur Uzunoglu studied civil engineering at the Vienna University of Technology, and made his PhD at the Graz University of Technology. In 2004, he founded convex ZT GmbH. Timur Uzunoglu is teaching Industrial Construction at the FH Joanneum Graz since 2005. He represents the British "Institution of Civil Engineers" in Austria.

Laszlo Gergely-Varga
Dipl.-Ing.
speaks: Romanian, Hungarian, German, English
convex consulting engineers s.r.l., Cluj-Napoca
Authorised Officer

Stanimir Vasilev
Electrical engineer (BSc), Civil engineer (MSc)
speaks: Bulgarian, English, German
convex ZT GmbH
Site manager

Veronika Vasileva
MSc
speaks: Bulgarian, English, German, Russian
convex ZT GmbH, Sophia
Architect & Civil engineer

Adem Visne
Dipl.-Ing.
speaks: Turkish, Bosnian, German, English
convex ZT GmbH, Graz
Contract manager

Paul Wegerer
MSc
speaks: German, English
clone:it GmbH, Graz
Civil engineer

Maximilian Weiland
BSc
speaks: German, English
convex ZT GmbH, Graz
Civil engineer

Bernd Weyringer
Ing.
speaks: German, English
Weyringer e.U., Graz
Civil engineer

Stephan Zwanzger
speaks: German, English
convex ZT GmbH, Graz
Engineer