The phenomenon of urban informality has coincided with rapid urbanization in Turkey from the 1950s onward. By the urban transformation act that was presented in 2012, formal developments and activities have increased in informal areas. Although recent activities are legal/formal, they have caused the reproduction of informality in these areas. With focusing on this spontaneous collaboration of formal and informal activities, this article seeks to understand the new urban fabric that was created by formal and informal builders who are both rule-breakers and rule-makers. The research was carried out in the Güzeltepe neighborhood, a complex neighborhood with a mix of squatter houses and renewal areas. The field study was conducted from 2014 to 2017 with site visits, photo analysis, and archival research. We will reveal and discuss legalization and upgrading processes, and the effects of this transformation. We will then analyze how informality operates as a logic of urban life.