This publication documents the ongoing interdisciplinary research project “A Prototype Pavilion in Textile Reinforced Concrete (TRC)” by the EPFL laboratories ALICE and IBETON and research partners from the FAUFBA, Salvador de Bahia, Brazil. The TRC Prototype Pavilion, built by students and researchers in civil engineering and architecture at EPFL Fribourg, is a proof of concept of a long-established research on TRC’s structural, spatial, tectonic and social potential. The construction of the pavilion is modular and conceived to be dismantled, its aim is in the first place to test and expose innovative and sustainable construction knowledge. The TRC Prototype Pavilion builds on research conducted during the ENAC teaching unit ‘Argamassa Armada’ (EPFL, since 2016) which is named after the Brazilian term for ferrocement. The teaching unit ‘Argamassa Armada’ analyzes and reiterates in textile reinforced concrete (TRC) selected structural elements developed by João da Gama Filgueiras Lima, Lelé (1932-2014) in ferrocement. This crossing of Brazilian industrial knowledge and contemporary research on non-corrosive fiber reinforcement creates the conceptual basis for the design, mold fabrication and casting of new slender elements in textile reinforced concrete, the conceptual basis for the TRC Prototype Pavilion (since 2019). It is intended to be a first step towards adaptable tectonic systems, a modular construction that will be further developed the next years and lead to a new lightweight building technique, forecasting a new and different conception and image of concrete construction at large the TRC Pavilion acts as a messenger for concrete as a social and sustainable "light" material.