diff --git a/OpenNest.Core/CNC/VariableDefinition.cs b/OpenNest.Core/CNC/VariableDefinition.cs
new file mode 100644
index 0000000..d74d87f
--- /dev/null
+++ b/OpenNest.Core/CNC/VariableDefinition.cs
@@ -0,0 +1,21 @@
+namespace OpenNest.CNC
+{
+    public sealed class VariableDefinition
+    {
+        public string Name { get; }
+        public string Expression { get; }
+        public double Value { get; }
+        public bool Inline { get; }
+        public bool Global { get; }
+
+        public VariableDefinition(string name, string expression, double value,
+            bool inline = false, bool global = false)
+        {
+            Name = name;
+            Expression = expression;
+            Value = value;
+            Inline = inline;
+            Global = global;
+        }
+    }
+}
diff --git a/OpenNest.Tests/CNC/VariableDefinitionTests.cs b/OpenNest.Tests/CNC/VariableDefinitionTests.cs
new file mode 100644
index 0000000..f965823
--- /dev/null
+++ b/OpenNest.Tests/CNC/VariableDefinitionTests.cs
@@ -0,0 +1,33 @@
+using OpenNest.CNC;
+
+namespace OpenNest.Tests.CNC;
+
+public class VariableDefinitionTests
+{
+    [Fact]
+    public void Constructor_SetsAllProperties()
+    {
+        var v = new VariableDefinition("diameter", "0.3", 0.3);
+        Assert.Equal("diameter", v.Name);
+        Assert.Equal("0.3", v.Expression);
+        Assert.Equal(0.3, v.Value);
+        Assert.False(v.Inline);
+        Assert.False(v.Global);
+    }
+
+    [Fact]
+    public void Constructor_WithFlags_SetsFlags()
+    {
+        var v = new VariableDefinition("width", "48.0", 48.0, inline: true, global: true);
+        Assert.True(v.Inline);
+        Assert.True(v.Global);
+    }
+
+    [Fact]
+    public void DefaultFlags_AreFalse()
+    {
+        var v = new VariableDefinition("x", "1", 1.0);
+        Assert.False(v.Inline);
+        Assert.False(v.Global);
+    }
+}
diff --git a/OpenNest.Tests/Fill/PatternTilerTests.cs b/OpenNest.Tests/Fill/PatternTilerTests.cs
index 81db4bb..4a49d81 100644
--- a/OpenNest.Tests/Fill/PatternTilerTests.cs
+++ b/OpenNest.Tests/Fill/PatternTilerTests.cs
@@ -1,3 +1,4 @@
+using OpenNest.CNC;
 using OpenNest.Engine.Fill;
 using OpenNest.Geometry;
 
@@ -7,11 +8,11 @@ public class PatternTilerTests
 {
     private static Drawing MakeSquareDrawing(double size)
     {
-        var pgm = new CNC.Program();
-        pgm.Codes.Add(new CNC.LinearMove(size, 0));
-        pgm.Codes.Add(new CNC.LinearMove(size, size));
-        pgm.Codes.Add(new CNC.LinearMove(0, size));
-        pgm.Codes.Add(new CNC.LinearMove(0, 0));
+        var pgm = new Program();
+        pgm.Codes.Add(new LinearMove(size, 0));
+        pgm.Codes.Add(new LinearMove(size, size));
+        pgm.Codes.Add(new LinearMove(0, size));
+        pgm.Codes.Add(new LinearMove(0, 0));
         return new Drawing("square", pgm);
     }
 
diff --git a/OpenNest.Tests/Geometry/PolygonHelperTests.cs b/OpenNest.Tests/Geometry/PolygonHelperTests.cs
index b896c0c..232a0f6 100644
--- a/OpenNest.Tests/Geometry/PolygonHelperTests.cs
+++ b/OpenNest.Tests/Geometry/PolygonHelperTests.cs
@@ -57,12 +57,12 @@ public class PolygonHelperTests
     public void ExtractPerimeterPolygon_InflatedPolygonIsLarger_ForCCWWinding()
     {
         // CCW winding: (0,0)→(10,0)→(10,10)→(0,10)→(0,0)
-        var pgm = new CNC.Program();
-        pgm.Codes.Add(new CNC.RapidMove(new Vector(0, 0)));
-        pgm.Codes.Add(new CNC.LinearMove(new Vector(10, 0)));
-        pgm.Codes.Add(new CNC.LinearMove(new Vector(10, 10)));
-        pgm.Codes.Add(new CNC.LinearMove(new Vector(0, 10)));
-        pgm.Codes.Add(new CNC.LinearMove(new Vector(0, 0)));
+        var pgm = new Program();
+        pgm.Codes.Add(new RapidMove(new Vector(0, 0)));
+        pgm.Codes.Add(new LinearMove(new Vector(10, 0)));
+        pgm.Codes.Add(new LinearMove(new Vector(10, 10)));
+        pgm.Codes.Add(new LinearMove(new Vector(0, 10)));
+        pgm.Codes.Add(new LinearMove(new Vector(0, 0)));
         var drawing = new Drawing("ccw-square", pgm);
 
         var noSpacing = PolygonHelper.ExtractPerimeterPolygon(drawing, 0);