diff --git a/.gitignore b/.gitignore
index 257db4c..bd660ac 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,3 +37,4 @@ build/
 dist/
 .old/
 test_assets/
+dev_notes/
diff --git a/abogen/Dockerfile b/abogen/Dockerfile
index 13fd1d0..6c5731e 100644
--- a/abogen/Dockerfile
+++ b/abogen/Dockerfile
@@ -52,6 +52,11 @@ ENV ABOGEN_UPLOAD_ROOT=/data/uploads \
   HF_HOME=/data/huggingface \
   HUGGINGFACE_HUB_CACHE=/data/huggingface/hub
 
-RUN mkdir -p /data/uploads /data/outputs /data/cache /data/voice-cache /data/huggingface
+# Create non-root user and setup permissions
+RUN useradd -m -u 1000 abogen \
+    && mkdir -p /data/uploads /data/outputs /data/cache /data/voice-cache /data/huggingface \
+    && chown -R abogen:abogen /data /app
+
+USER abogen
 
 CMD ["abogen"]
diff --git a/abogen/pronunciation_store.py b/abogen/pronunciation_store.py
index a6f0f4e..88524ff 100644
--- a/abogen/pronunciation_store.py
+++ b/abogen/pronunciation_store.py
@@ -86,6 +86,7 @@ def load_overrides(language: str, tokens: Iterable[str]) -> Dict[str, Dict[str,
     normalized_tokens = {normalize_token(token) for token in tokens if token}
     if not normalized_tokens:
         return {}
+    # Use parameterized queries to prevent SQL injection
     placeholders = ",".join("?" for _ in normalized_tokens)
     with _DB_LOCK:
         conn = _connect()
diff --git a/abogen/utils.py b/abogen/utils.py
index a41cd66..e984157 100644
--- a/abogen/utils.py
+++ b/abogen/utils.py
@@ -327,6 +327,9 @@ def create_process(cmd, stdin=None, text=True, capture_output=False):
 
     # Determine shell usage: use shell only for string commands
     use_shell = isinstance(cmd, str)
+    if use_shell:
+        logger.warning("Security Warning: create_process called with string command. Prefer using a list of arguments to avoid shell injection risks.")
+
     kwargs = {
         "shell": use_shell,
         "stdout": subprocess.PIPE,
diff --git a/abogen/web/app.py b/abogen/web/app.py
index f09dcfb..3a9db9b 100644
--- a/abogen/web/app.py
+++ b/abogen/web/app.py
@@ -8,7 +8,7 @@ from typing import Any, Optional
 
 from flask import Flask
 
-from abogen.utils import get_user_cache_path, get_user_output_path
+from abogen.utils import get_user_cache_path, get_user_output_path, get_user_settings_dir
 
 from .conversion_runner import run_conversion_job
 from .service import build_service
@@ -50,6 +50,26 @@ def _default_dirs() -> tuple[Path, Path]:
     return uploads, outputs
 
 
+def _get_secret_key() -> str:
+    env_key = os.environ.get("ABOGEN_SECRET_KEY")
+    if env_key:
+        return env_key
+
+    try:
+        settings_dir = Path(get_user_settings_dir())
+        settings_dir.mkdir(parents=True, exist_ok=True)
+        secret_file = settings_dir / ".secret_key"
+        if secret_file.exists():
+            return secret_file.read_text(encoding="utf-8").strip()
+
+        key = os.urandom(24).hex()
+        secret_file.write_text(key, encoding="utf-8")
+        return key
+    except Exception:
+        # Fallback if we can't write to settings dir
+        return os.urandom(24).hex()
+
+
 def create_app(config: Optional[dict[str, Any]] = None) -> Flask:
     uploads_dir, outputs_dir = _default_dirs()
 
@@ -59,7 +79,7 @@ def create_app(config: Optional[dict[str, Any]] = None) -> Flask:
         template_folder="templates",
     )
     base_config = {
-        "SECRET_KEY": os.environ.get("ABOGEN_SECRET_KEY", os.urandom(16)),
+        "SECRET_KEY": _get_secret_key(),
         "UPLOAD_FOLDER": str(uploads_dir),
         "OUTPUT_FOLDER": str(outputs_dir),
         "MAX_CONTENT_LENGTH": 1024 * 1024 * 400,  # 400 MB uploads
diff --git a/abogen/web/routes.py b/abogen/web/routes.py
index c430df0..07c418f 100644
--- a/abogen/web/routes.py
+++ b/abogen/web/routes.py
@@ -4511,6 +4511,7 @@ def enqueue_job() -> ResponseReturnValue:
     original_name: str
 
     if file and file.filename:
+        # secure_filename prevents path traversal attacks
         filename = secure_filename(file.filename)
         if not filename:
             return redirect(url_for("web.index"))