System and methods for generating round keys for a cryptographic operation are disclosed. The systems and method can use logic circuits that are operable to: obtain first inputs and second inputs; perform a bit-mixer operation on each of the first inputs and the second inputs; and generate round keys based on the performing the bit-mixer operation. The first inputs include a plurality of equal sized subkeys from a key material that is divided into a plurality of equal sized key material sub-blocks, a cipher key and the second inputs include a random input, one or more previous round keys, a round number. The cryptographic operation includes a cipher, a hash function, or a stream generator. The bit-mixer operation includes an exclusive-OR (XOR) tree, a substitution-permutation network, or a double-mix Feistel network, or a Rotate-Add-XOR (RAX) construction.