diff --git a/.jules/bolt.md b/.jules/bolt.md
index f1a8c146..d66e480e 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -77,3 +77,6 @@ Optimized metric route processing to O(N) by creating a mapping of routes direct
 ## 2024-07-13 - [Optimize Export Dictionary FK lookups]
 **Learning:** Found O(N * C * E) performance bottleneck in ERD export dictionaries due to repeated array searching with `edges.some()` inside a nested loop over nodes and columns.
 **Action:** Replace repeated linear array scans for edges by precomputing O(1) Set lookups of foreign key column handles per node before looping.
+## 2024-05-14 - Map/Set construction array allocation overhead
+**Learning:** Initializing Maps or Sets using `new Set(array.map(...))` creates unnecessary intermediate arrays and puts pressure on the garbage collector. In highly interactive applications (like this React ERD), frequent GC pauses cause jank.
+**Action:** Populate Maps and Sets iteratively using `for...of` loops, avoiding `.map()` when building lookup structures.
diff --git a/frontend/src/erd/businessGroups.ts b/frontend/src/erd/businessGroups.ts
index f60edd24..838b50c2 100644
--- a/frontend/src/erd/businessGroups.ts
+++ b/frontend/src/erd/businessGroups.ts
@@ -41,7 +41,11 @@ export function uniqueBusinessGroupId(
   existingGroups: BusinessGroup[],
 ): string {
   const baseId = buildBusinessGroupId(name);
-  const existingIds = new Set(existingGroups.map((group) => group.id));
+  // ⚡ Bolt: Populate Set iteratively to avoid array allocation overhead (O(N)) from .map()
+  const existingIds = new Set<string>();
+  for (const group of existingGroups) {
+    existingIds.add(group.id);
+  }
   if (!existingIds.has(baseId)) return baseId;
   let suffix = 2;
   while (existingIds.has(`${baseId}_${suffix}`)) {