diff --git a/app.py b/app.py
index 3c12509..523f712 100644
--- a/app.py
+++ b/app.py
@@ -21,6 +21,7 @@ JOBS_DIR.mkdir(exist_ok=True)
 # In Docker: /usr/bin/freecadcmd, lokal (mac): via env setzen, wenn du willst
 FREECAD_TIMEOUT_SEC = int(os.environ.get("FREECAD_TIMEOUT_SEC", "1200"))
 FREECADCMD = (os.environ.get("FREECADCMD") or "").strip() or "/opt/conda/envs/fc/bin/freecadcmd"
+FREECADCMD = "/usr/bin/freecadcmd"
 
 ALLOWED_MATERIALS = [
     ("stainless", "Edelstahl"),
@@ -97,7 +98,8 @@ try:
     mod_dir = os.path.expanduser("~/.local/share/FreeCAD/Mod")
     if os.path.isdir(mod_dir) and mod_dir not in sys.path:
         sys.path.append(mod_dir)
-    sm_dir = os.path.join(mod_dir, \"SheetMetal\")
+#    sm_dir = os.path.join(mod_dir, \"SheetMetal\")
+    sm_dir = os.path.join(mod_dir, \"sheetmetal\")
     if os.path.isdir(sm_dir) and sm_dir not in sys.path:
         sys.path.append(sm_dir)
 
@@ -125,13 +127,29 @@ finally:
     cmd = [FREECADCMD, "run_stepanalyser.py"]
 
     env = os.environ.copy()
-    # In linuxserver containers the writable, persistent home is /config
+
+    # Remove anything that can make embedded Python pick up the venv / wrong stdlib
+    for k in list(env.keys()):
+        if k.startswith("PYTHON"):
+            env.pop(k, None)
+
+    # Also de-venv-ify PATH if you want to be extra safe
+    # (optional, but helpful if the venv puts shims first)
+    # env["PATH"] = "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
+
+    # Make locale sane (Py_EncodeLocale happens very early)
+    env.setdefault("LANG", "C.UTF-8")
+    env.setdefault("LC_ALL", "C.UTF-8")
+    env.setdefault("LC_CTYPE", "C.UTF-8")
+
+    # Your existing settings
     env["HOME"] = env.get("HOME") or "/config"
-    env["HOME"] = "/config"  # enforce for consistent expanduser() + Mod discovery
-
-    # Headless Qt hints (works on Debian-based hosts too)
     env.setdefault("QT_QPA_PLATFORM", "offscreen")
-
+    env["LANG"] = "C"
+    env["LC_ALL"] = "C"
+    env["LC_CTYPE"] = "C"
+    env["PYTHONUTF8"] = "1"
+    env["PYTHONCOERCECLOCALE"] = "1"
     timeout = FREECAD_TIMEOUT_SEC
 
     log_path = job_dir / "run.log"
@@ -143,7 +161,8 @@ finally:
             log_fp.write("=== STEPANALYSER START ===\n")
             log_fp.write(f"Command: {cmd}\n")
             log_fp.flush()
-
+            log_fp.write(f"Sanitized env: PYTHONHOME={env.get('PYTHONHOME')} PYTHONPATH={env.get('PYTHONPATH')}\n")
+            log_fp.write(f"Locale: LANG={env.get('LANG')} LC_ALL={env.get('LC_ALL')} LC_CTYPE={env.get('LC_CTYPE')}\n")
             proc = subprocess.Popen(
                 cmd,
                 cwd=str(job_dir),