diff --git a/dagger/component_test.go b/dagger/component_test.go
index 02d4bc45..5ed1a6b5 100644
--- a/dagger/component_test.go
+++ b/dagger/component_test.go
@@ -5,6 +5,48 @@ import (
 	"testing"
 )
 
+// Test that default values in spec are applied at the component level
+// See issue #19
+func TestComponentDefaults(t *testing.T) {
+	t.Skip("FIXME: issue #19")
+	cc := &Compiler{}
+	v, err := cc.Compile("", `
+#dagger: compute: [
+	{
+        do: "fetch-container"
+        ref: "busybox"
+	},
+    {
+        do: "exec"
+        args: ["sh", "-c", """
+            echo hello > /tmp/out
+        """]
+//      dir: "/"
+    }
+]
+`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	c, err := v.Component()
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Issue #19 is triggered by:
+	// 1. Compile component
+	// 2. Get compute script from component
+	// 3. Walk script
+	s, err := c.ComputeScript()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := s.Walk(context.TODO(), func(op *Op) error {
+		return nil
+	}); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestValidateEmptyComponent(t *testing.T) {
 	cc := &Compiler{}
 	v, err := cc.Compile("", "#dagger: compute: _")
diff --git a/dagger/script_test.go b/dagger/script_test.go
index b5a2eb65..ccc192cc 100644
--- a/dagger/script_test.go
+++ b/dagger/script_test.go
@@ -6,6 +6,44 @@ import (
 	"testing"
 )
 
+// Test that default values in spec are applied
+func TestScriptDefaults(t *testing.T) {
+	cc := &Compiler{}
+	v, err := cc.Compile("", `
+    {
+        do: "exec"
+        args: ["sh", "-c", """
+            echo hello > /tmp/out
+        """]
+//      dir: "/"
+    }
+`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	op, err := v.Op()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := op.Validate(); err != nil {
+		t.Fatal(err)
+	}
+	dir, err := op.Get("dir").String()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if dir != "/" {
+		t.Fatal(dir)
+	}
+	t.Skip("FIXME: issue #19")
+	// Walk triggers issue #19 UNLESS optional fields removed from spec.cue
+	if err := op.Walk(context.TODO(), func(op *Op) error {
+		return nil
+	}); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestValidateEmptyValue(t *testing.T) {
 	cc := &Compiler{}
 	v, err := cc.Compile("", "#dagger: compute: _")
diff --git a/examples/tests/repro-19/main.cue b/examples/tests/repro-19/main.cue
new file mode 100644
index 00000000..3016d7d9
--- /dev/null
+++ b/examples/tests/repro-19/main.cue
@@ -0,0 +1,15 @@
+package test
+
+#dagger: compute: [
+	{
+		do:  "fetch-container"
+		ref: "busybox"
+	},
+	{
+		do: "exec"
+		args: ["sh", "-c", """
+			    echo hello > /tmp/out
+			"""]
+		//                dir: "/"
+	},
+]