An interger hash function is a bijection in the domain of N-bit unsigned integers with hashing properties. To make a good hash function, for each flip in input bit, roughly 1/2 of the output bit should flip (known as "high avalanche effect"). Furthermore, there should be no correlation between flipped input bits and output bits (known as "low bias"). The author of this article describes an algorithm to generate integer hash functions by composing reversible functions, and test the two hashing properties on the function to find the best ones.