diff --git a/dwg2dxf-api/Dockerfile b/dwg2dxf-api/Dockerfile
index e697dd9..f07e1f8 100644
--- a/dwg2dxf-api/Dockerfile
+++ b/dwg2dxf-api/Dockerfile
@@ -1,42 +1,27 @@
-FROM ubuntu:24.04 AS builder
-
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends \
-        build-essential autoconf automake libtool pkg-config \
-        wget ca-certificates && \
-    rm -rf /var/lib/apt/lists/*
-
-# Build libredwg from source (not available in apt repos)
-ARG LIBREDWG_VERSION=0.13.3
-RUN wget -q "https://github.com/LibreDWG/libredwg/releases/download/${LIBREDWG_VERSION}/libredwg-${LIBREDWG_VERSION}.tar.xz" && \
-    tar xf "libredwg-${LIBREDWG_VERSION}.tar.xz" && \
-    cd "libredwg-${LIBREDWG_VERSION}" && \
-    ./configure --prefix=/usr/local --disable-static --disable-docs && \
-    make -j"$(nproc)" && \
-    make install
-
-# ---
-
 FROM ubuntu:24.04
 
-# Copy only the built binaries and libraries
-COPY --from=builder /usr/local/bin/dwg2dxf /usr/local/bin/
-COPY --from=builder /usr/local/lib/libredwg* /usr/local/lib/
-
-RUN ldconfig && \
-    apt-get update && \
-    apt-get install -y --no-install-recommends python3 python3-pip && \
+# ODA File Converter needs Qt libs + virtual framebuffer for headless mode
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+        python3 python3-pip wget ca-certificates \
+        xvfb libxcb-xinerama0 libxcb-icccm4 libxcb-image0 \
+        libxcb-keysyms1 libxcb-randr0 libxcb-render-util0 \
+        libxcb-shape0 libxcb-xkb1 libxkbcommon0 libxkbcommon-x11-0 \
+        libglib2.0-0 libgl1 libfontconfig1 libfreetype6 && \
     pip3 install --no-cache-dir --break-system-packages flask && \
     apt-get purge -y python3-pip && \
     apt-get autoremove -y && \
     rm -rf /var/lib/apt/lists/*
 
+# Download and install ODA File Converter
+RUN wget -q "https://download.opendesign.com/guestfiles/Demo/ODAFileConverter_QT6_lnxX64_8.3dll_25.12.deb" \
+        -O /tmp/oda.deb && \
+    dpkg -i /tmp/oda.deb || apt-get install -f -y && \
+    rm /tmp/oda.deb
+
 WORKDIR /app
 COPY app.py .
 
-RUN useradd --system --no-create-home converter
-USER converter
-
 EXPOSE 5001
 
 HEALTHCHECK --interval=30s --timeout=5s --retries=3 \
diff --git a/dwg2dxf-api/app.py b/dwg2dxf-api/app.py
index 216ee49..993da66 100644
--- a/dwg2dxf-api/app.py
+++ b/dwg2dxf-api/app.py
@@ -1,6 +1,8 @@
-"""Minimal DWG-to-DXF conversion microservice via libredwg."""
+"""DWG-to-DXF conversion microservice via ODA File Converter."""
 
+import glob
 import os
+import shutil
 import subprocess
 import tempfile
 import uuid
@@ -11,15 +13,16 @@ app = Flask(__name__)
 
 MAX_FILE_SIZE = 100 * 1024 * 1024  # 100 MB
 
+# ODA File Converter installs here on Ubuntu
+ODA_BIN = "/usr/bin/ODAFileConverter"
+
 
 @app.route("/health", methods=["GET"])
 def health():
-    """Health check — verifies dwg2dxf binary is callable."""
-    try:
-        subprocess.run(["dwg2dxf", "--version"], capture_output=True, timeout=5)
-        return jsonify({"status": "ok", "dwg2dxf": "available"}), 200
-    except Exception as e:
-        return jsonify({"status": "error", "detail": str(e)}), 503
+    """Health check — verifies ODA File Converter is installed."""
+    if os.path.isfile(ODA_BIN) and os.access(ODA_BIN, os.X_OK):
+        return jsonify({"status": "ok", "converter": "ODAFileConverter"}), 200
+    return jsonify({"status": "error", "detail": "ODAFileConverter not found"}), 503
 
 
 @app.route("/convert", methods=["POST"])
@@ -38,11 +41,13 @@ def convert():
         c if c.isalnum() or c in "._-" else "_" for c in original_name
     )
 
-    tmp_dir = os.path.join(tempfile.gettempdir(), f"dwg-{uuid.uuid4().hex}")
-    os.makedirs(tmp_dir, exist_ok=True)
+    work_dir = os.path.join(tempfile.gettempdir(), f"dwg-{uuid.uuid4().hex}")
+    input_dir = os.path.join(work_dir, "in")
+    output_dir = os.path.join(work_dir, "out")
+    os.makedirs(input_dir, exist_ok=True)
+    os.makedirs(output_dir, exist_ok=True)
 
-    input_path = os.path.join(tmp_dir, safe_name)
-    output_path = input_path.rsplit(".", 1)[0] + ".dxf"
+    input_path = os.path.join(input_dir, safe_name)
 
     try:
         uploaded.save(input_path)
@@ -51,21 +56,30 @@ def convert():
         if file_size > MAX_FILE_SIZE:
             return jsonify({"error": f"File too large ({file_size} bytes)."}), 413
 
+        # ODA File Converter: input_dir output_dir version type recurse audit
+        # ACAD2018 = output DXF version, DXF = output format, 0 = no recurse, 1 = audit
         result = subprocess.run(
-            ["dwg2dxf", input_path],
+            [
+                "xvfb-run", "--auto-servernum", "--server-args=-screen 0 1x1x24",
+                ODA_BIN, input_dir, output_dir, "ACAD2018", "DXF", "0", "1",
+            ],
             capture_output=True,
             timeout=120,
         )
 
-        if not os.path.exists(output_path):
+        # Find the output DXF file
+        dxf_files = glob.glob(os.path.join(output_dir, "*.dxf"))
+        if not dxf_files:
             stderr = result.stderr.decode("utf-8", errors="replace")
-            return jsonify({
-                "error": f"Conversion failed: {stderr or 'no output file'}"
-            }), 500
+            stdout = result.stdout.decode("utf-8", errors="replace")
+            detail = stderr or stdout or "No output file produced"
+            return jsonify({"error": f"Conversion failed: {detail}"}), 500
 
+        dxf_path = dxf_files[0]
         dxf_name = safe_name.rsplit(".", 1)[0] + ".dxf"
+
         return send_file(
-            output_path,
+            dxf_path,
             mimetype="application/dxf",
             as_attachment=True,
             download_name=dxf_name,
@@ -78,15 +92,7 @@ def convert():
         return jsonify({"error": f"Unexpected error: {str(e)}"}), 500
 
     finally:
-        for f in os.listdir(tmp_dir):
-            try:
-                os.unlink(os.path.join(tmp_dir, f))
-            except OSError:
-                pass
-        try:
-            os.rmdir(tmp_dir)
-        except OSError:
-            pass
+        shutil.rmtree(work_dir, ignore_errors=True)
 
 
 if __name__ == "__main__":