⚡ Bolt: [performance improvement] Fix N+1 file I/O for loadConfig in WorktreesService

.jules/bolt.md

@@ -4,3 +4,6 @@
 ## 2026-05-16 - [Batch FeathersJS user fetches with $in operator to fix N+1 query]
 **Learning:** FeathersJS allows passing `$in` clauses through the query parameter (e.g. `user_id: { $in: ownerIds }`). When writing custom Feathers service logic, you can easily parse this array and pass it to Drizzle's `inArray()` to perform a batched query, instead of looping over `service.get(id)` causing N+1 database roundtrips.
 **Action:** When implementing or updating custom Feathers `find()` methods, extract and parse the `$in` parameters to support batched Drizzle `inArray()` lookups, and always replace `Promise.all(ids.map(id => service.get(id)))` with a single batched `find()` call.
+## 2024-05-24 - [Avoid N+1 file I/O operations in loops]
+**Learning:** Functions like `loadConfig()` which perform synchronous or asynchronous file I/O (such as `fs.readFile` and `yaml.load`) create significant latency when called iteratively inside loops or array mappings. They cause O(N) disk operations for operations that should only take O(1).
+**Action:** When performing mapping or looping over arrays in business logic or handlers, always hoist configuration loading or expensive file-system checks outside the loop, evaluate it once, and pass the cached result as an argument to the per-item processor.

apps/agor-daemon/src/services/worktrees.ts

@@ -10,7 +10,13 @@ import { existsSync } from 'node:fs';
 import { mkdir } from 'node:fs/promises';
 import { homedir } from 'node:os';
 import { dirname, join } from 'node:path';
-import { ENVIRONMENT, isWorktreeRbacEnabled, loadConfig, PAGINATION } from '@agor/core/config';
+import {
+  type AgorConfig,
+  ENVIRONMENT,
+  isWorktreeRbacEnabled,
+  loadConfig,
+  PAGINATION,
+} from '@agor/core/config';
 import { type Database, WorktreeRepository, type WorktreeWithZoneAndSessions } from '@agor/core/db';
 import { renderWorktreeSnapshot } from '@agor/core/environment/render-snapshot';
 import type { Application } from '@agor/core/feathers';
@@ -226,8 +232,10 @@ export class WorktreesService extends DrizzleService<Worktree, Partial<Worktree>
    * so admins can set org-wide defaults in config.yaml. Explicit values on the
    * input always win; defaults fill in only when the caller omits the field.
    */
-  private async applyWorktreeCreateDefaults(data: Partial<Worktree>): Promise<Partial<Worktree>> {
-    const config = await loadConfig();
+  private applyWorktreeCreateDefaults(
+    data: Partial<Worktree>,
+    config: AgorConfig
+  ): Partial<Worktree> {
     const defaults = config.worktrees;
     if (!defaults) return data;
 
@@ -251,13 +259,15 @@ export class WorktreesService extends DrizzleService<Worktree, Partial<Worktree>
     data: Partial<Worktree> | Partial<Worktree>[],
     params?: WorktreeParams
   ): Promise<Worktree | Worktree[]> {
+    const config = await loadConfig();
+
     if (Array.isArray(data)) {
-      const withDefaults = await Promise.all(
-        data.map((item) => this.applyWorktreeCreateDefaults(item))
-      );
+      // ⚡ Bolt Performance Optimization:
+      // Load config once outside the loop instead of reading and parsing the file O(N) times.
+      const withDefaults = data.map((item) => this.applyWorktreeCreateDefaults(item, config));
       return super.create(withDefaults, params) as Promise<Worktree[]>;
     }
-    const withDefaults = await this.applyWorktreeCreateDefaults(data);
+    const withDefaults = this.applyWorktreeCreateDefaults(data, config);
     return super.create(withDefaults, params) as Promise<Worktree>;
   }