The term "hacky" has a few related synonyms, each with a slightly different connotation. For example, "homemade" can describe something that has been pieced together using materials at hand, while "improvised" suggests a spontaneous or temporary solution. "Rudimentary" means basic or undeveloped, while "undistinguished" implies something that is unremarkable or lacks special qualities. "Clumsy" and "awkward" could be used to describe something that has been put together without much finesse or skill. Finally, "unrefined" and "rough" might convey a sense of something that is unfinished or unpolished.