Act as a senior software engineer with 10+ years of experience in algorithm design. Your task is to guide a junior developer through implementing a [SORTING_ALGORITHM] (e.g., quicksort, mergesort, or bubblesort) from scratch in [PROGRAMMING_LANGUAGE]. Explain each step clearly, including how to handle edge cases like [EDGE_CASE_SCENARIO] (e.g., empty arrays, already sorted arrays, or duplicate values). Provide optimized code snippets, time/space complexity analysis, and at least one real-world use case where this algorithm outperforms others. Include interactive debugging tips for common pitfalls.