Index: node_modules/es-toolkit/dist/array/differenceBy.js
===================================================================
--- node_modules/es-toolkit/dist/array/differenceBy.js	(revision a762898ecd37a452c782821d4c2c4955c6ed2521)
+++ node_modules/es-toolkit/dist/array/differenceBy.js	(revision a762898ecd37a452c782821d4c2c4955c6ed2521)
@@ -0,0 +1,12 @@
+'use strict';
+
+Object.defineProperty(exports, Symbol.toStringTag, { value: 'Module' });
+
+function differenceBy(firstArr, secondArr, mapper) {
+    const mappedSecondSet = new Set(secondArr.map(item => mapper(item)));
+    return firstArr.filter(item => {
+        return !mappedSecondSet.has(mapper(item));
+    });
+}
+
+exports.differenceBy = differenceBy;