diff --git a/src/applications/differential/customfield/DifferentialAuditorsField.php b/src/applications/differential/customfield/DifferentialAuditorsField.php
--- a/src/applications/differential/customfield/DifferentialAuditorsField.php
+++ b/src/applications/differential/customfield/DifferentialAuditorsField.php
@@ -16,7 +16,7 @@
   }
 
   public function getValueForStorage() {
-    return json_encode($this->getValue());
+    return phutil_json_encode($this->getValue());
   }
 
   public function setValueFromStorage($value) {
@@ -28,33 +28,16 @@
     return $this;
   }
 
-  public function shouldAppearInCommitMessage() {
-    return true;
-  }
-
-  public function shouldAllowEditInCommitMessage() {
-    return true;
-  }
-
   public function canDisableField() {
     return false;
   }
 
-  public function getRequiredHandlePHIDsForCommitMessage() {
-    return nonempty($this->getValue(), array());
-  }
-
-  public function parseCommitMessageValue($value) {
-    return $this->parseObjectList(
-      $value,
-      array(
-        PhabricatorPeopleUserPHIDType::TYPECONST,
-        PhabricatorProjectProjectPHIDType::TYPECONST,
-      ));
+  public function shouldAppearInEditEngine() {
+    return true;
   }
 
-  public function renderCommitMessageValue(array $handles) {
-    return $this->renderObjectList($handles);
+  public function shouldAppearInCommitMessage() {
+    return true;
   }
 
   public function shouldAppearInConduitTransactions() {
@@ -65,4 +48,8 @@
     return new ConduitPHIDListParameterType();
   }
 
+  public function shouldAppearInApplicationTransactions() {
+    return true;
+  }
+
 }
diff --git a/src/applications/differential/field/DifferentialAuditorsCommitMessageField.php b/src/applications/differential/field/DifferentialAuditorsCommitMessageField.php
--- a/src/applications/differential/field/DifferentialAuditorsCommitMessageField.php
+++ b/src/applications/differential/field/DifferentialAuditorsCommitMessageField.php
@@ -22,6 +22,14 @@
     return 'phabricator:auditors';
   }
 
+  public function isFieldEditable() {
+    return true;
+  }
+
+  public function isTemplateField() {
+    return false;
+  }
+
   public function readFieldValueFromConduit($value) {
     return $this->readStringListFieldValueFromConduit($value);
   }
diff --git a/src/applications/differential/field/DifferentialCommitMessageField.php b/src/applications/differential/field/DifferentialCommitMessageField.php
--- a/src/applications/differential/field/DifferentialCommitMessageField.php
+++ b/src/applications/differential/field/DifferentialCommitMessageField.php
@@ -182,7 +182,7 @@
   protected function isCustomFieldEnabled($key) {
     $field_list = PhabricatorCustomField::getObjectFields(
       new DifferentialRevision(),
-      PhabricatorCustomField::ROLE_VIEW);
+      DifferentialCustomField::ROLE_COMMITMESSAGE);
 
     $fields = $field_list->getFields();
     return isset($fields[$key]);
diff --git a/src/infrastructure/customfield/editor/PhabricatorCustomFieldEditField.php b/src/infrastructure/customfield/editor/PhabricatorCustomFieldEditField.php
--- a/src/infrastructure/customfield/editor/PhabricatorCustomFieldEditField.php
+++ b/src/infrastructure/customfield/editor/PhabricatorCustomFieldEditField.php
@@ -37,6 +37,10 @@
   }
 
   protected function buildControl() {
+    if ($this->getIsConduitOnly()) {
+      return null;
+    }
+
     $field = $this->getCustomField();
     $clone = clone $field;
 
diff --git a/src/infrastructure/customfield/engineextension/PhabricatorCustomFieldEditEngineExtension.php b/src/infrastructure/customfield/engineextension/PhabricatorCustomFieldEditEngineExtension.php
--- a/src/infrastructure/customfield/engineextension/PhabricatorCustomFieldEditEngineExtension.php
+++ b/src/infrastructure/customfield/engineextension/PhabricatorCustomFieldEditEngineExtension.php
@@ -31,7 +31,7 @@
 
     $field_list = PhabricatorCustomField::getObjectFields(
       $object,
-      PhabricatorCustomField::ROLE_EDIT);
+      PhabricatorCustomField::ROLE_EDITENGINE);
 
     $field_list->setViewer($viewer);
 
diff --git a/src/infrastructure/customfield/field/PhabricatorCustomField.php b/src/infrastructure/customfield/field/PhabricatorCustomField.php
--- a/src/infrastructure/customfield/field/PhabricatorCustomField.php
+++ b/src/infrastructure/customfield/field/PhabricatorCustomField.php
@@ -33,6 +33,7 @@
   const ROLE_GLOBALSEARCH             = 'GlobalSearch';
   const ROLE_CONDUIT                  = 'conduit';
   const ROLE_HERALD                   = 'herald';
+  const ROLE_EDITENGINE = 'EditEngine';
 
 
 /* -(  Building Applications with Custom Fields  )--------------------------- */
@@ -292,6 +293,9 @@
         return $this->shouldAppearInTransactionMail();
       case self::ROLE_HERALD:
         return $this->shouldAppearInHerald();
+      case self::ROLE_EDITENGINE:
+        return $this->shouldAppearInEditView() ||
+               $this->shouldAppearInEditEngine();
       case self::ROLE_DEFAULT:
         return true;
       default:
@@ -1120,12 +1124,19 @@
       return $this->proxy->newStandardEditField();
     }
 
+    if (!$this->shouldAppearInEditView()) {
+      $conduit_only = true;
+    } else {
+      $conduit_only = false;
+    }
+
     return $this->newEditField()
       ->setKey($this->getFieldKey())
       ->setEditTypeKey($this->getModernFieldKey())
       ->setLabel($this->getFieldName())
       ->setDescription($this->getFieldDescription())
       ->setTransactionType($this->getApplicationTransactionType())
+      ->setIsConduitOnly($conduit_only)
       ->setValue($this->getNewValueForApplicationTransactions());
   }
 
@@ -1146,6 +1157,16 @@
     return false;
   }
 
+  /**
+   * @task edit
+   */
+  public function shouldAppearInEditEngine() {
+    if ($this->proxy) {
+      return $this->proxy->shouldAppearInEditEngine();
+    }
+    return false;
+  }
+
 
   /**
    * @task edit