diff --git a/composer.json b/composer.json
index b488e41..dbdea99 100644
--- a/composer.json
+++ b/composer.json
@@ -17,7 +17,7 @@
     },
     "autoload-dev": {
         "psr-4": {
-            "Garden\\JSON\\Tests\\": "src"
+            "Garden\\JSON\\Tests\\": "tests"
         }
     },
     "require-dev": {
diff --git a/src/ReferenceResolverTrait.php b/src/ReferenceResolverTrait.php
new file mode 100644
index 0000000..a41f329
--- /dev/null
+++ b/src/ReferenceResolverTrait.php
@@ -0,0 +1,81 @@
+<?php
+/**
+ * @author Todd Burry <todd@vanillaforums.com>
+ * @copyright 2009-2020 Vanilla Forums Inc.
+ * @license MIT
+ */
+
+namespace Garden\JSON;
+
+
+trait ReferenceResolverTrait {
+    /**
+     * Escape a JSON reference field.
+     *
+     * @param string $field The reference field to escape.
+     * @return string Returns an escaped reference.
+     */
+    private static function escapeRef(string $field): string {
+        return str_replace(['~', '/', '$'], ['~0', '~1', '~2'], $field);
+    }
+
+    /**
+     * Unescape a JSON reference segment.
+     *
+     * @param string $str The segment to unescapeRef.
+     * @return string Returns the unescaped string.
+     */
+    private static function unescapeRef(string $str): string {
+        return str_replace(['~2', '~1', '~0'], ['$', '/', '~'], $str);
+    }
+
+    /**
+     * Explode a references into its individual parts.
+     *
+     * @param string $ref A JSON reference.
+     * @return string[] The individual parts of the reference.
+     */
+    private static function explodeRef(string $ref): array {
+        return array_map([self::class, 'unescapeRef'], explode('/', $ref));
+    }
+
+    /**
+     * Resolve a JSON reference.
+     *
+     * @param int|string $ref The reference to resolve.
+     * @param mixed $context The current data context to lookup.
+     * @param mixed $root The root data context for absolute references.
+     * @param bool $found Set to **true** if the reference was found or **false** otherwise.
+     * @return mixed Returns the value at the reference.
+     */
+    private function resolveReference($ref, $context, $root, bool &$found = null) {
+        $found = true;
+
+        if ($ref === '') {
+            return $context;
+        } elseif ($ref === '/') {
+            return $root;
+        } elseif (is_int($ref)) {
+            return $context[$ref];
+        } elseif ($ref[0] === '/') {
+            $ref = substr($ref, 1);
+            $context = $root;
+        }
+
+        $parts = self::explodeRef($ref);
+        $result = $context;
+        foreach ($parts as $key) {
+            if (!is_array($result)) {
+                $found = false;
+                return null;
+            } elseif (array_key_exists($key, $result)) {
+                $result = $result[$key];
+            } else {
+                $found = false;
+                return null;
+            }
+        }
+
+        return $result;
+    }
+}
diff --git a/src/Transformer.php b/src/Transformer.php
index 0a89042..f15ac5d 100644
--- a/src/Transformer.php
+++ b/src/Transformer.php
@@ -11,6 +11,8 @@
  * A class that transforms data based on a specification.
  */
 final class Transformer {
+    use ReferenceResolverTrait;
+
     /**
      * @var string|array The transform spec.
      */
@@ -88,76 +90,6 @@ private function transformInternal($spec, $data, $root, string $path) {
         return $result;
     }
 
-    /**
-     * Resolve a JSON reference.
-     *
-     * @param int|string $ref The reference to resolve.
-     * @param mixed $context The current data context to lookup.
-     * @param mixed $root The root data context for absolute references.
-     * @param bool $found Set to **true** if the reference was found or **false** otherwise.
-     * @return mixed Returns the value at the reference.
-     */
-    private function resolveReference($ref, $context, $root, bool &$found = null) {
-        $found = true;
-
-        if ($ref === '') {
-            return $context;
-        } elseif ($ref === '/') {
-            return $root;
-        } elseif (is_int($ref)) {
-            return $context[$ref];
-        } elseif ($ref[0] === '/') {
-            $ref = substr($ref, 1);
-            $context = $root;
-        }
-
-        $parts = self::explodeRef($ref);
-        $result = $context;
-        foreach ($parts as $key) {
-            if (!is_array($result)) {
-                $found = false;
-                return null;
-            } elseif (array_key_exists($key, $result)) {
-                $result = $result[$key];
-            } else {
-                $found = false;
-                return null;
-            }
-        }
-
-        return $result;
-    }
-
-    /**
-     * Escape a JSON reference field.
-     *
-     * @param string $field The reference field to escape.
-     * @return string Returns an escaped reference.
-     */
-    private static function escapeRef(string $field): string {
-        return str_replace(['~', '/', '$'], ['~0', '~1', '~2'], $field);
-    }
-
-    /**
-     * Unescape a JSON reference segment.
-     *
-     * @param string $str The segment to unescapeRef.
-     * @return string Returns the unescaped string.
-     */
-    private static function unescapeRef(string $str): string {
-        return str_replace(['~2', '~1', '~0'], ['$', '/', '~'], $str);
-    }
-
-    /**
-     * Explode a references into its individual parts.
-     *
-     * @param string $ref A JSON reference.
-     * @return string[] The individual parts of the reference.
-     */
-    private static function explodeRef(string $ref): array {
-        return array_map([self::class, 'unescapeRef'], explode('/', $ref));
-    }
-
     /**
      * Resolve a control expression.
      *