diff --git a/src/cq_cli/cqcodecs/cq_codec_stl.py b/src/cq_cli/cqcodecs/cq_codec_stl.py
index 401ff11..3f67e64 100644
--- a/src/cq_cli/cqcodecs/cq_codec_stl.py
+++ b/src/cq_cli/cqcodecs/cq_codec_stl.py
@@ -20,10 +20,17 @@ def convert(build_result, output_file=None, error_file=None, output_opts=None):
 
     # The exporters will add extra output that we do not want, so suppress it
     with helpers.suppress_stdout_stderr():
+        # There should be a shape in the build results
+        result = build_result.results[0].shape
+
+        # If the build result is an assembly, we have to make it a compound before trying to export it as SVG
+        if type(result).__name__ == "Assembly":
+            result = result.toCompound()
+        else:
+            result = result.val()
+
         # Put the STL output into the temp file
-        build_result.results[0].shape.val().exportStl(
-            temp_file, linearDeflection, angularDeflection, True
-        )
+        result.exportStl(temp_file, linearDeflection, angularDeflection, True)
 
     # Read the STL output back in
     with open(temp_file, "r") as file:
diff --git a/src/cq_cli/cqcodecs/cq_codec_svg.py b/src/cq_cli/cqcodecs/cq_codec_svg.py
index b01017c..bc7d6be 100644
--- a/src/cq_cli/cqcodecs/cq_codec_svg.py
+++ b/src/cq_cli/cqcodecs/cq_codec_svg.py
@@ -10,12 +10,16 @@ def convert(build_result, output_file=None, error_file=None, output_opts=None):
 
     # The exporters will add extra output that we do not want, so suppress it
     with helpers.suppress_stdout_stderr():
+        # There should be a shape in the build results
+        result = build_result.results[0].shape
+
+        # If the build result is an assembly, we have to make it a compound before trying to export it as SVG
+        if type(result).__name__ == "Assembly":
+            result = result.toCompound()
+
         # Put the STEP output into the temp file
         exporters.export(
-            build_result.results[0].shape,
-            temp_file,
-            exporters.ExportTypes.SVG,
-            opt=output_opts,
+            result, temp_file, exporters.ExportTypes.SVG, opt=output_opts,
         )
 
     # Read the STEP output back in
diff --git a/tests/test_stl_codec.py b/tests/test_stl_codec.py
index 45ceab5..d6f6648 100644
--- a/tests/test_stl_codec.py
+++ b/tests/test_stl_codec.py
@@ -57,3 +57,22 @@ def test_stl_codec_quality():
     low_detail = len(out2.decode().split("\n"))
 
     assert low_detail < high_detail
+
+
+def test_stl_codec_with_assembly():
+    """
+    Test of the STL codec plugin with a CadQuery assembly.
+    """
+    test_file = helpers.get_test_file_location("cube_assy.py")
+
+    command = [
+        "python",
+        "src/cq_cli/main.py",
+        "--codec",
+        "stl",
+        "--infile",
+        test_file,
+    ]
+    out, err, exitcode = helpers.cli_call(command)
+
+    assert out.decode().split("\n")[0].replace("\r", "") == "solid "
diff --git a/tests/test_svg_codec.py b/tests/test_svg_codec.py
index ade12a6..1e3561b 100644
--- a/tests/test_svg_codec.py
+++ b/tests/test_svg_codec.py
@@ -23,3 +23,27 @@ def test_svg_codec():
         out.decode().split("\n")[0].replace("\r", "")
         == '<?xml version="1.0" encoding="UTF-8" standalone="no"?>'
     )
+
+
+def test_svg_codec_with_assembly():
+    """
+    Test of the SVG codec plugin with a CadQuery assembly.
+    """
+    test_file = helpers.get_test_file_location("cube_assy.py")
+
+    command = [
+        "python",
+        "src/cq_cli/main.py",
+        "--codec",
+        "svg",
+        "--infile",
+        test_file,
+        "--outputopts",
+        "width:100;height:100;marginLeft:12;marginTop:12;showAxes:False;projectionDir:(0.5,0.5,0.5);strokeWidth:0.25;strokeColor:(255,0,0);hiddenColor:(0,0,255);showHidden:True;",
+    ]
+    out, err, exitcode = helpers.cli_call(command)
+
+    assert (
+        out.decode().split("\n")[0].replace("\r", "")
+        == '<?xml version="1.0" encoding="UTF-8" standalone="no"?>'
+    )