He studied electrical and telecommunications engineering at the Swiss Federal Institute of Technology in Zurich and gained a diploma.

His tasks included building workshops and mobile telephone exchanges, while also training telecommunications non-commissioned officers.

As a senior engineer, he was involved in the construction of the Buenos Aires - Rosario telephone line through the Paraná River in 1929.

He planned a submarine cable running through the Río de la Plata to connect the Argentine and Uruguayan capitals in 1930.

[4] Hilfiker joined the Swiss Federal Railways (SBB) as an engineer in construction department III in 1932.

[10] Hilfiker created an actual corporate design for Therma and restructured the manufacturing processes for the new fitted kitchens.