diff --git a/lib/set_koords.py b/lib/set_koords.py
new file mode 100644
index 0000000..43baf38
--- /dev/null
+++ b/lib/set_koords.py
@@ -0,0 +1,96 @@
+"""
+Erzeugt benannte Koordinatensystem-Bloecke in DXF-Dateien.
+
+Jeder Block enthaelt drei Linien vom Ursprung:
+  - rot(1)   X-Achse, Laenge 1
+  - gruen(3) Y-Achse, Laenge 2
+  - blau(5)  Z-Achse, Laenge 3
+
+Die 3D-Rotation erfolgt ueber die Transformation des INSERT-Entities.
+"""
+
+import math
+import ezdxf
+from ezdxf.math import Matrix44
+
+
+# Block-Linien: (color, dx, dy, dz)
+KS_LINES = [
+    (1, 1.0, 0.0, 0.0),   # rot, X-Achse, Laenge 1
+    (3, 0.0, 2.0, 0.0),   # gruen, Y-Achse, Laenge 2
+    (5, 0.0, 0.0, 3.0),   # blau, Z-Achse, Laenge 3
+]
+
+
+def _ensure_block(doc, block_name):
+    """Erzeugt den Block falls er noch nicht existiert."""
+    if block_name not in doc.blocks:
+        blk = doc.blocks.new(name=block_name)
+        for color, dx, dy, dz in KS_LINES:
+            blk.add_line(
+                start=(0, 0, 0),
+                end=(dx, dy, dz),
+                dxfattribs={"color": color},
+            )
+    return block_name
+
+
+def _ensure_layer(doc, layer_name="_KOORDINATENSYSTEME"):
+    """Stellt sicher, dass der Layer existiert."""
+    if layer_name not in doc.layers:
+        doc.layers.add(layer_name)
+
+
+def insert_ks(msp, name, point, rx=0, ry=0, rz=0):
+    """
+    Erzeugt ein benanntes Koordinatensystem als Block-Referenz.
+
+    Args:
+        msp: Modelspace oder Block des Ziel-Dokuments.
+        name: Block-Name (z.B. "K1", "K2", "K3", "K4").
+        point: Einfuegepunkt als (x, y, z) Tupel.
+        rx: Rotation um X-Achse in Grad.
+        ry: Rotation um Y-Achse in Grad.
+        rz: Rotation um Z-Achse in Grad.
+
+    Returns:
+        Das erzeugte INSERT-Entity.
+    """
+    doc = msp.doc
+    _ensure_layer(doc)
+    _ensure_block(doc, name)
+
+    insert = msp.add_blockref(
+        name,
+        insert=point,
+        dxfattribs={"layer": "_KOORDINATENSYSTEME"},
+    )
+
+    # 3D-Rotation via Transformationsmatrix
+    m = Matrix44.chain(
+        Matrix44.translate(-point[0], -point[1], -point[2]),
+        Matrix44.x_rotate(math.radians(rx)),
+        Matrix44.y_rotate(math.radians(ry)),
+        Matrix44.z_rotate(math.radians(rz)),
+        Matrix44.translate(point[0], point[1], point[2]),
+    )
+    insert.transform(m)
+
+    return insert
+
+
+if __name__ == "__main__":
+    doc = ezdxf.new(dxfversion="R2010")
+    msp = doc.modelspace()
+
+    insert_ks(msp, "K1", (0, 0, 0))
+    insert_ks(msp, "K2", (10, 0, 0), rz=90)
+    insert_ks(msp, "K3", (20, 0, 0), ry=45)
+    insert_ks(msp, "K4", (30, 0, 0), rx=30, ry=45, rz=60)
+
+    import os
+    results_dir = os.environ.get("DXFM_RESULTS", "results")
+    os.makedirs(results_dir, exist_ok=True)
+    out_path = os.path.join(results_dir, "ks_test.dxf")
+    doc.saveas(out_path)
+    print(f"Testdatei gespeichert: {out_path}")