function trieBuilder(word_list) {
      const root = {};
      for (const word of words_list) {
        let node = root;
        for (const char of word) {
          let nextNode = node[char];
          if (!nextNode) node[char] = nextNode = {};
          node = nextNode;
        }
        node._ = 1; // mark the nodes that are endings of real words
      }

      function findChildren(node, prefix, list, maxLength) {
        if (node._ === 1) list.push(prefix);
        for (const char in node) {
          findChildren(node[char], prefix + char, list, maxLength);
          if (list.length >= maxLength) return list;
        }
        return list;
      }

      function findSuffixes(prefix, maxLength) {
        prefix = prefix.toLowerCase();
        let node = root;
        for (const char of prefix) {
          let nextNode = node[char];
          if (!nextNode) return [""];
          node = nextNode;
        }
        let words = findChildren(node, prefix, [], maxLength);
        return words;
      }

      return {root, findSuffixes};
    }