I began by defining the trie structure, outlining the node representation with child references and a boolean flag for end-of-word. I implemented the methods for insertion and search capabilities. While coding the autocomplete functionality, I made sure to return all possible completions for a given prefix. The interviewer seemed engaged while I explained the complexity of operations; however, I stumbled on edge cases regarding case sensitivity and character normalization, leading to some back-and-forth which felt unproductive.