In this paper, we introduce the open-source PivPav backend tool for reconfigurable computing. Essentially, PivPav provides an interface to a library of digital circuits that are kept in a database. For each circuit, an extensive set of metadata is made available through an application programming interface. PivPav is agnostic of the kind of circuits that are stored in the library, but it provides an interface to commonly used circuit generators. The integrated benchmarking framework allows for processing and measuring the circuits with FPGA CAD tools under a variety of implementation constraints. This process characterizes each circuit, for example with its latency, maximum operating frequency, power consumption, input and output interfaces, etc. While PivPav is useful as a stand-alone benchmarking tool, its main purpose is to act as a building block in higher-level tool flows for reconfigurable computing. We present three case studies, that illustrate the use of PivPav for the purpose...