His first employment was at the construction company of baron Pittel which was designing and building armored concrete constructions.
He participated in building factories, aqueducts for hydroelectric power plants, collector within the Belgrade sewage system, reinforced bridges; he patented new type of reinforced concrete ribbed ceiling and published the first paper on armored concrete named ''Contribution to the theory of reinforced armored pillars''. He published the second paper on the same subject based on new results in 1906. In 1908. he published a paper titled ''On membranes of same opposition'' in which he proves that the ideal shape for water reservoir of equally thick walls is that of a drop of water.
He was employed as highest ranking engineer in the biggest Austro-Hungarian construction company as of 1908. His six patents were officially recognized and his reputation in the profession was enormous, bringing abundant financial income.
Anyhow, when he was offered the post of the professor of applied mathematics at the Belgrade University, he decided to accept it. Vocation of an academic would yield more free time for scientific research than vocation of an engineer, and his dream of becoming academic and achieving intellectual freedom dated from his early days. He was aware that his income would be significantly lower and that Belgrade was less sophisticated socially then Vienna, but he still decided to dedicate himself to the science and to participate in the development of the Belgrade University as much as he could.