TPF Sp. z o.o. implements for PKP Polskie Linie Kolejowe S.A. the following service: Author's supervision and upgrade of 447 rail line within the project called The works on Warszawa Włochy – Grodzisk Mazowiecki rail line.

The upgrade of Warszawa Włochy – Grodzisk Mazowiecki rail line consisted of the reconstruction of track system, correction of profile and plan geometric systems, stations and stops reconstruction: Warszawa Włochy, Warszawa Ursus, Piastów, Pruszków, Brwinów, Milanówek aimed at adjustment to the of movement of people with disabilities, construction of a new signal box Warszawa Włochy, demolition of the existing signal box, construction of a new station in Parzniew, construction and reconstruction of railroad subgrade drainage system, roads, stations and stops, reconstruction and engineering objects and crossroads, level crossings, construction of platforms and underground crossings, construction of easy access roads, construction and reconstruction and reconstruction of the existing engineering objects, construction of overhead contact line power facilities, station objects and external lighting of the investment.