NIST is conducting a process for the standardization of post-quantum cryptosystems, i.e., cryptosystems that are resistant to attacks by both traditional and quantum computers and that can thus substitute the traditional public-key cryptography solutions which are expected to be broken by quantum computers in the next decades. This manuscript provides an overview and a comparison of the existing state-of-the-art implementations of the BIKE QC-MDPC code-based post-quantum KEM, a candidate in NIST's PQC standardization process. We consider both software, hardware, and mixed hardware-software implementations and evaluate their performance and, for hardware ones, their resource utilization.