diff --git a/modules/datastore/tests/src/Unit/Plugin/QueueWorker/ImportJobTest.php b/modules/datastore/tests/src/Unit/Plugin/QueueWorker/ImportJobTest.php
index e5207f3dc4..39f8c8474d 100644
--- a/modules/datastore/tests/src/Unit/Plugin/QueueWorker/ImportJobTest.php
+++ b/modules/datastore/tests/src/Unit/Plugin/QueueWorker/ImportJobTest.php
@@ -174,6 +174,7 @@ public function testSerialization() {
    *
    */
   public function testMultiplePasses() {
+    $this->markTestIncomplete('This does not always use more than one pass.');
     $resource = new DatastoreResource(1, __DIR__ . "/../../../../data/Bike_Lane.csv", "text/csv");
 
     $storage = new Memory();
diff --git a/modules/metastore/tests/src/Functional/OnPreReferenceTest.php b/modules/metastore/tests/src/Functional/OnPreReferenceTest.php
index 8c88db05b3..231968f5b3 100644
--- a/modules/metastore/tests/src/Functional/OnPreReferenceTest.php
+++ b/modules/metastore/tests/src/Functional/OnPreReferenceTest.php
@@ -6,7 +6,9 @@
 use weitzman\DrupalTestTraits\ExistingSiteBase;
 
 /**
- *
+ * Run tests in separate processes, since they rely on the value of
+ *   drupal_static().
+ * @runTestsInSeparateProcesses
  */
 class OnPreReferenceTest extends ExistingSiteBase {
   use CleanUp;
diff --git a/phpunit.xml b/phpunit.xml
index bdeb809091..e1e33203b3 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -12,6 +12,7 @@
       <directory>.</directory>
     </include>
     <exclude>
+      <file>rector.php</file>
       <directory>modules/common/tests</directory>
       <directory>modules/datastore/tests</directory>
       <directory>modules/dkan_js_frontend/tests</directory>
diff --git a/tests/src/Functional/DatasetTest.php b/tests/src/Functional/DatasetTest.php
index 35eac47e8c..088441dec9 100644
--- a/tests/src/Functional/DatasetTest.php
+++ b/tests/src/Functional/DatasetTest.php
@@ -91,9 +91,10 @@ public function testResourcePurgePublished() {
 
   /**
    * Test the resource purger when the default moderation state is 'draft'.
+   *
+   * @runInSeparateProcess
    */
   public function testResourcePurgeDraft() {
-    $this->markTestSkipped('Flaky test fails inconsistently, typically line 119.');
     $id_1 = uniqid(__FUNCTION__ . '1');
     $id_2 = uniqid(__FUNCTION__ . '2');
     $id_3 = uniqid(__FUNCTION__ . '3');