Universalify simplifies the creation of universal modules that function seamlessly in both callback-based and promise-based environments. By wrapping asynchronous functions, this package generates a single function capable of handling either callbacks or returning a promise based on the presence of a callback function. This eliminates the need for maintaining separate callback and promise versions of your module, ultimately streamlining development and reducing code duplication. It's ideal for libraries aiming for broad compatibility and cleaner asynchronous handling.