From d1c163f20cd0de7b023097d09a4d8d60cc899905 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Wed, 1 Apr 2026 03:50:07 +0000
Subject: [PATCH] Refactor scanners from actor to struct for true concurrency

Co-authored-by: acebytes <2820910+acebytes@users.noreply.github.com>
---
 .jules/bolt.md                                    |  3 +++
 Sources/Cacheout/Scanner/CacheScanner.swift       | 10 ++++++----
 Sources/Cacheout/Scanner/NodeModulesScanner.swift |  7 ++++---
 3 files changed, 13 insertions(+), 7 deletions(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 0000000..2705ee8
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,3 @@
+## 2024-05-18 - Fix actor serialization to enable true parallel scanning
+**Learning:** In Swift structured concurrency, using an `actor` to manage a `withTaskGroup` where tasks invoke synchronous, blocking I/O (like `FileManager` operations) directly on the actor inadvertently serializes the tasks, preventing parallelism.
+**Action:** For stateless components interacting with thread-safe dependencies (like `FileManager.default`), use `struct`s or `nonisolated` methods to allow tasks to execute concurrently across threads and unlock true parallel scanning.
diff --git a/Sources/Cacheout/Scanner/CacheScanner.swift b/Sources/Cacheout/Scanner/CacheScanner.swift
index 3ce3e9c..702befd 100644
--- a/Sources/Cacheout/Scanner/CacheScanner.swift
+++ b/Sources/Cacheout/Scanner/CacheScanner.swift
@@ -1,13 +1,15 @@
 /// # CacheScanner — Parallel Cache Category Scanner
 ///
-/// An `actor` that scans all registered cache categories concurrently using
+/// A `struct` that scans all registered cache categories concurrently using
 /// Swift's structured concurrency (`TaskGroup`). Each category is scanned in
 /// its own child task for maximum parallelism.
 ///
 /// ## Thread Safety
 ///
-/// Uses the `actor` isolation model to ensure thread-safe access to internal state.
-/// All public methods are `async` and can be called from any concurrency context.
+/// Uses a stateless `struct` instead of an `actor` to prevent unintentional
+/// serialization of child tasks when invoking `scanCategory`. Because all
+/// methods operate on local variables and thread-safe dependencies (`FileManager.default`),
+/// concurrent execution is safe and truly parallel.
 ///
 /// ## Disk Size Calculation
 ///
@@ -26,7 +28,7 @@
 
 import Foundation
 
-actor CacheScanner {
+struct CacheScanner {
     private let fileManager = FileManager.default
 
     func scanAll(_ categories: [CacheCategory]) async -> [ScanResult] {
diff --git a/Sources/Cacheout/Scanner/NodeModulesScanner.swift b/Sources/Cacheout/Scanner/NodeModulesScanner.swift
index 3ed4d8c..bec959b 100644
--- a/Sources/Cacheout/Scanner/NodeModulesScanner.swift
+++ b/Sources/Cacheout/Scanner/NodeModulesScanner.swift
@@ -1,6 +1,6 @@
 /// # NodeModulesScanner — Recursive node_modules Finder
 ///
-/// An `actor` that recursively searches common developer project directories
+/// A `struct` that recursively searches common developer project directories
 /// for `node_modules` folders. Designed to find abandoned or stale dependencies
 /// that consume significant disk space.
 ///
@@ -21,14 +21,15 @@
 ///
 /// ## Performance
 ///
-/// - Parallel scanning of root directories via `TaskGroup`
+/// - Parallel scanning of root directories via `TaskGroup` (using a stateless `struct`
+///   avoids actor serialization, unlocking true concurrent filesystem traversal)
 /// - Early termination when `node_modules` found (no deeper recursion)
 /// - Skip list eliminates most irrelevant directories
 /// - `maxDepth` cap prevents excessive filesystem traversal
 
 import Foundation
 
-actor NodeModulesScanner {
+struct NodeModulesScanner {
     private let fileManager = FileManager.default
 
     /// Common directories where developers keep projects