diff --git a/pkg/kusttest/kusttestharness.go b/pkg/kusttest/kusttestharness.go
index ac5445d39..7b2e49e36 100644
--- a/pkg/kusttest/kusttestharness.go
+++ b/pkg/kusttest/kusttestharness.go
@@ -31,16 +31,16 @@ type KustTestHarness struct {
 }
 
 func NewKustTestHarness(t *testing.T, path string) *KustTestHarness {
-	return NewKustTestHarnessWithPluginConfig(
+	return newHarness(
 		t, path, plugins.DefaultPluginConfig())
 }
 
 func NewKustTestPluginHarness(t *testing.T, path string) *KustTestHarness {
-	return NewKustTestHarnessWithPluginConfig(
+	return newHarness(
 		t, path, plugins.ActivePluginConfig())
 }
 
-func NewKustTestHarnessWithPluginConfig(
+func newHarness(
 	t *testing.T, path string,
 	pc *types.PluginConfig) *KustTestHarness {
 	return NewKustTestHarnessFull(t, path, loader.RestrictionRootOnly, pc)
diff --git a/pkg/plugins/compiler.go b/pkg/plugins/compiler.go
index 9efd7c91e..a07dbd04a 100644
--- a/pkg/plugins/compiler.go
+++ b/pkg/plugins/compiler.go
@@ -41,7 +41,7 @@ type Compiler struct {
 }
 
 // DefaultSrcRoot guesses where the user
-// has her ${g}/${v}/${k}.go files.
+// has her ${g}/${v}/$lower(${k})/${k}.go files.
 func DefaultSrcRoot() (string, error) {
 	var nope []string
 	var root string
@@ -109,8 +109,14 @@ func (b *Compiler) Compile(g, v, k string) error {
 	}
 	srcFile := filepath.Join(b.srcRoot, g, v, lowK, k) + ".go"
 	if !FileExists(srcFile) {
-		return fmt.Errorf(
-			"cannot find source %s", srcFile)
+		// Handy for tests of lone plugins.
+		s := k + ".go"
+		if !FileExists(s) {
+			return fmt.Errorf(
+				"cannot find source at '%s' or '%s'", srcFile, s)
+
+		}
+		srcFile = s
 	}
 	commands := []string{
 		"build",