diff --git a/core/modules/migrate/src/MigrationBuilder.php b/core/modules/migrate/src/MigrationBuilder.php
index e4c4658e1ebfc9363240e853c89980755cd81685..bdf3e4e42a09fe50d7d4d9371dd6e80014918585 100644
--- a/core/modules/migrate/src/MigrationBuilder.php
+++ b/core/modules/migrate/src/MigrationBuilder.php
@@ -13,7 +13,7 @@
 /**
  * Builds migration entities from migration templates.
  */
-class MigrationBuilder {
+class MigrationBuilder implements MigrationBuilderInterface {
 
   /**
    * The builder plugin manager.
@@ -33,14 +33,7 @@ public function __construct(MigratePluginManager $builder_manager) {
   }
 
   /**
-   * Builds migration entities from templates.
-   *
-   * @param array $templates
-   *   The parsed templates (each of which is an array parsed from YAML), keyed
-   *   by ID.
-   *
-   * @return \Drupal\migrate\Entity\MigrationInterface[]
-   *   The migration entities derived from the templates.
+   * {@inheritdoc}
    */
   public function createMigrations(array $templates) {
     /** @var \Drupal\migrate\Entity\MigrationInterface[] $migrations */
diff --git a/core/modules/migrate/src/MigrationBuilderInterface.php b/core/modules/migrate/src/MigrationBuilderInterface.php
new file mode 100644
index 0000000000000000000000000000000000000000..66f3078e53df59d41343f7a17be083ef479f1f33
--- /dev/null
+++ b/core/modules/migrate/src/MigrationBuilderInterface.php
@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\migrate\MigrationBuilderInterface.
+ */
+
+namespace Drupal\migrate;
+
+/**
+ * The migration builder interface.
+ */
+interface MigrationBuilderInterface {
+
+  /**
+   * Builds migration entities from templates.
+   *
+   * @param array $templates
+   *   The parsed templates (each of which is an array parsed from YAML), keyed
+   *   by ID.
+   *
+   * @return \Drupal\migrate\Entity\MigrationInterface[]
+   *   The migration entities derived from the templates.
+   */
+  public function createMigrations(array $templates);
+
+}