diff --git a/joj3_config_generator/convert.py b/joj3_config_generator/convert.py
index 1834689..6031218 100644
--- a/joj3_config_generator/convert.py
+++ b/joj3_config_generator/convert.py
@@ -1,5 +1,5 @@
 import os
-from typing import List
+from typing import Set
 
 from joj3_config_generator.models import joj1, repo, result, task
 from joj3_config_generator.models.const import CACHE_ROOT, JOJ3_CONFIG_ROOT
@@ -35,10 +35,10 @@ def convert(repo_conf: repo.Config, task_conf: task.Config) -> result.Config:
     # Construct health check stage
     if not repo_conf.force_skip_health_check_on_test or not current_test:
         result_conf.stage.stages.append(get_health_check_config(repo_conf))
-    cached: List[str] = []
+    cached: Set[str] = set()
     # Convert each stage in the task configuration
     for task_stage in task_conf.stages:
-        executor_with_config, cached = get_executor_with_config(task_stage, cached)
+        executor_with_config = get_executor_with_config(task_stage, cached)
         conf_stage = get_conf_stage(task_stage, executor_with_config)
         conf_stage = fix_result_detail(task_stage, conf_stage)
         conf_stage = fix_dummy(task_stage, conf_stage)
diff --git a/joj3_config_generator/processers/task.py b/joj3_config_generator/processers/task.py
index fd2c632..5ad6234 100644
--- a/joj3_config_generator/processers/task.py
+++ b/joj3_config_generator/processers/task.py
@@ -1,6 +1,6 @@
 import re
 import shlex
-from typing import List, Tuple
+from typing import Set
 
 from joj3_config_generator.models import result, task
 from joj3_config_generator.models.const import JOJ3_CONFIG_ROOT
@@ -33,8 +33,8 @@ def get_conf_stage(
 
 
 def get_executor_with_config(
-    task_stage: task.Stage, cached: List[str]
-) -> Tuple[result.ExecutorWith, List[str]]:
+    task_stage: task.Stage, cached: Set[str]
+) -> result.ExecutorWith:
     file_import = task_stage.files.import_
     copy_in_files = [file for file in file_import if file not in cached]
     file_export = task_stage.files.export
@@ -61,8 +61,8 @@ def get_executor_with_config(
     )
     for file in file_export:
         if file not in cached:
-            cached.append(file)
-    return (executor_with_config, cached)
+            cached.add(file)
+    return executor_with_config
 
 
 def fix_keyword(
diff --git a/tests/convert/basic/task.json b/tests/convert/basic/task.json
index 8fb84c8..375540f 100644
--- a/tests/convert/basic/task.json
+++ b/tests/convert/basic/task.json
@@ -222,11 +222,11 @@
                                 }
                             },
                             "copyInCached": {
-                                "h7/build/ex2": "h7/build/ex2",
-                                "h7/build/ex2-asan": "h7/build/ex2-asan",
-                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan",
                                 "h7/build/ex2-msan": "h7/build/ex2-msan",
-                                "h7/build/compile_commands.json": "h7/build/compile_commands.json"
+                                "h7/build/ex2-asan": "h7/build/ex2-asan",
+                                "h7/build/compile_commands.json": "h7/build/compile_commands.json",
+                                "h7/build/ex2": "h7/build/ex2",
+                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan"
                             },
                             "copyInDir": ".",
                             "copyOut": [
@@ -322,11 +322,11 @@
                                 }
                             },
                             "copyInCached": {
-                                "h7/build/ex2": "h7/build/ex2",
-                                "h7/build/ex2-asan": "h7/build/ex2-asan",
-                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan",
                                 "h7/build/ex2-msan": "h7/build/ex2-msan",
-                                "h7/build/compile_commands.json": "h7/build/compile_commands.json"
+                                "h7/build/ex2-asan": "h7/build/ex2-asan",
+                                "h7/build/compile_commands.json": "h7/build/compile_commands.json",
+                                "h7/build/ex2": "h7/build/ex2",
+                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan"
                             },
                             "copyInDir": ".",
                             "copyOut": [
@@ -444,11 +444,11 @@
                             "cpuSetLimit": "",
                             "copyIn": {},
                             "copyInCached": {
-                                "h7/build/ex2": "h7/build/ex2",
-                                "h7/build/ex2-asan": "h7/build/ex2-asan",
-                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan",
                                 "h7/build/ex2-msan": "h7/build/ex2-msan",
-                                "h7/build/compile_commands.json": "h7/build/compile_commands.json"
+                                "h7/build/ex2-asan": "h7/build/ex2-asan",
+                                "h7/build/compile_commands.json": "h7/build/compile_commands.json",
+                                "h7/build/ex2": "h7/build/ex2",
+                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan"
                             },
                             "copyInDir": ".",
                             "copyOut": [
@@ -542,11 +542,11 @@
                             "cpuSetLimit": "",
                             "copyIn": {},
                             "copyInCached": {
-                                "h7/build/ex2": "h7/build/ex2",
-                                "h7/build/ex2-asan": "h7/build/ex2-asan",
-                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan",
                                 "h7/build/ex2-msan": "h7/build/ex2-msan",
-                                "h7/build/compile_commands.json": "h7/build/compile_commands.json"
+                                "h7/build/ex2-asan": "h7/build/ex2-asan",
+                                "h7/build/compile_commands.json": "h7/build/compile_commands.json",
+                                "h7/build/ex2": "h7/build/ex2",
+                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan"
                             },
                             "copyInDir": ".",
                             "copyOut": [
@@ -639,11 +639,11 @@
                             "cpuSetLimit": "",
                             "copyIn": {},
                             "copyInCached": {
-                                "h7/build/ex2": "h7/build/ex2",
-                                "h7/build/ex2-asan": "h7/build/ex2-asan",
-                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan",
                                 "h7/build/ex2-msan": "h7/build/ex2-msan",
-                                "h7/build/compile_commands.json": "h7/build/compile_commands.json"
+                                "h7/build/ex2-asan": "h7/build/ex2-asan",
+                                "h7/build/compile_commands.json": "h7/build/compile_commands.json",
+                                "h7/build/ex2": "h7/build/ex2",
+                                "h7/build/ex2-ubsan": "h7/build/ex2-ubsan"
                             },
                             "copyInDir": ".",
                             "copyOut": [