diff --git a/rewind/core.py b/rewind/core.py
index 1a04290..b73a69b 100644
--- a/rewind/core.py
+++ b/rewind/core.py
@@ -2,6 +2,7 @@
 import os
 import datetime
 import subprocess
+import tempfile
 
 from rewind.state import load_state, add_marker_to_state, remove_marker_from_state
 from rewind.config import Config
@@ -120,61 +121,62 @@ def _get_ts_files(start_timestamp: float, end_timestamp: float) -> tuple[list[st
     return selected_files, start_offset, end_offset
 
 def _concat_ts_files(file_list: list[str], start_offset: float, end_offset: float, length: float, output_file: str) -> None:
-    with open("file_list.txt", "w") as f:
+    tmp_file = tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False)
+    try:
         for file_path in file_list:
-            f.write(f"file '{file_path}'\n")
+            tmp_file.write(f"file '{file_path}'\n")
+        tmp_file.close()
 
-    cmd = ["ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostats", "-progress", "pipe:1"]
-    if start_offset > 0:
-        cmd += ["-ss", str(start_offset)]
-    if end_offset > 0:
-        cmd += ["-t", str(length)]
-    cmd += ["-f", "concat", "-safe", "0", "-i", "file_list.txt", "-c", "copy"]
-    cmd.append(output_file)
+        cmd = ["ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostats", "-progress", "pipe:1"]
+        if start_offset > 0:
+            cmd += ["-ss", str(start_offset)]
+        if end_offset > 0:
+            cmd += ["-t", str(length)]
+        cmd += ["-f", "concat", "-safe", "0", "-i", tmp_file.name, "-c", "copy"]
+        cmd.append(output_file)
 
-    process = subprocess.Popen(
-        cmd,
-        stdout=subprocess.PIPE,
-        stderr=subprocess.PIPE,
-        text=True,
-        bufsize=1,
-    )
+        process = subprocess.Popen(
+            cmd,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            text=True,
+            bufsize=1,
+        )
 
-    init_ms_val = 0
-    init_ms_val_set = False
+        init_ms_val = 0
+        init_ms_val_set = False
 
-    with tqdm(
-        total=length,
-        unit="s",
-        unit_scale=True,
-        unit_divisor=60,
-        desc="Processing",
-        leave=True,
-    ) as pbar:
-        for line in process.stdout:
-            line = line.strip()
-            
+        with tqdm(
+            total=length,
+            unit="s",
+            unit_scale=True,
+            unit_divisor=60,
+            desc="Processing",
+            leave=True,
+        ) as pbar:
+            for line in process.stdout:  # type: ignore[union-attr]
+                line = line.strip()
 
-            if line.startswith("out_time_ms="):
-                out_time_ms = int(line.split("=")[1])
+                if line.startswith("out_time_ms="):
+                    out_time_ms = int(line.split("=")[1])
 
-                if not init_ms_val_set:
-                    init_ms_val = out_time_ms
-                    init_ms_val_set = True
-                out_time_ms -= init_ms_val
+                    if not init_ms_val_set:
+                        init_ms_val = out_time_ms
+                        init_ms_val_set = True
+                    out_time_ms -= init_ms_val
 
-                seconds = abs(out_time_ms / 1_000_000)
-                pbar.n = min(seconds, length)
-                pbar.refresh()
+                    seconds = abs(out_time_ms / 1_000_000)
+                    pbar.n = min(seconds, length)
+                    pbar.refresh()
 
-            elif line == "progress=end":
-                break
+                elif line == "progress=end":
+                    break
 
-    ret = process.wait()
-    os.remove("file_list.txt")
-
-    if ret != 0:
-        raise RuntimeError("ffmpeg failed")
+        ret = process.wait()
+        if ret != 0:
+            raise RuntimeError("ffmpeg failed")
+    finally:
+        os.unlink(tmp_file.name)
 
 def get_duration(file_path: str) -> float:
     result = subprocess.run(