Looks like the Rax version is based on React-Redux 4.x, which was was primarily a single file and kept most of the logic in a React component. React-Redux v5 is a complete internal rewrite that pushes the logic out into memoized selector functions.

In fact, it appears to be 98%-ish the same as React-Redux v4.4.6. They've added semicolons, swapped out the React imports for Rax imports, and shuffled the order of some of the methods, but the code is effectively identical.