verilog-to-routing (vtr) is an open source cad flow for fpga devices. vtr's main purpose is to map a given circuit described in verilog, a hardware description language, on a given fpga architecture for research and development purposes; the fpga architecture targeted could be a novel architecture that a researcher wishes to explore, or it could be an existing commercial fpga whose architecture has been captured in the vtr input format. the vtr project has many contributors, with lead collaborating universities being the university of toronto, the university of new brunswick, and the university of california, berkeley . additional contributors include google, the university of utah, princeton university, altera, intel, texas instruments, and mit lincoln lab.