Post-quantum cryptography is public-key cryptography resistant to future quantum computers. In this talk we will talk about a post-quantum cryptosystem called DME (Double Matrix Exponentiation) based on high degree polynomials on a small number of variables that I have developed (using ideas of Algebraic Geometry), patented and present it to the NIST contest to choose the future post-quantum cryptography standard. I will also present some open questions related with the algebraic cryptanalysis of the scheme DME and the actual state of the NIST process to choose a quantum safe standard.