diff --git a/src/applications/config/schema/PhabricatorConfigStorageSchema.php b/src/applications/config/schema/PhabricatorConfigStorageSchema.php
index e1c8bda4cd..61475ae350 100644
--- a/src/applications/config/schema/PhabricatorConfigStorageSchema.php
+++ b/src/applications/config/schema/PhabricatorConfigStorageSchema.php
@@ -1,219 +1,219 @@
 <?php
 
 abstract class PhabricatorConfigStorageSchema extends Phobject {
 
   const ISSUE_MISSING = 'missing';
   const ISSUE_MISSINGKEY = 'missingkey';
   const ISSUE_SURPLUS = 'surplus';
   const ISSUE_SURPLUSKEY = 'surpluskey';
   const ISSUE_CHARSET = 'charset';
   const ISSUE_COLLATION = 'collation';
   const ISSUE_COLUMNTYPE = 'columntype';
   const ISSUE_NULLABLE = 'nullable';
   const ISSUE_KEYCOLUMNS = 'keycolumns';
   const ISSUE_UNIQUE = 'unique';
   const ISSUE_SUBNOTE = 'subnote';
   const ISSUE_SUBWARN = 'subwarn';
   const ISSUE_SUBFAIL = 'subfail';
 
   const STATUS_OKAY = 'okay';
   const STATUS_NOTE = 'note';
   const STATUS_WARN = 'warn';
   const STATUS_FAIL = 'fail';
 
   private $issues = array();
   private $name;
 
   abstract public function newEmptyClone();
   abstract protected function compareToSimilarSchema(
     PhabricatorConfigStorageSchema $expect);
   abstract protected function getSubschemata();
 
   public function compareTo(PhabricatorConfigStorageSchema $expect) {
     if (get_class($expect) != get_class($this)) {
       throw new Exception(pht('Classes must match to compare schemata!'));
     }
 
     if ($this->getName() != $expect->getName()) {
       throw new Exception(pht('Names must match to compare schemata!'));
     }
 
     return $this->compareToSimilarSchema($expect);
   }
 
   public function setName($name) {
     $this->name = $name;
     return $this;
   }
 
   public function getName() {
     return $this->name;
   }
 
   public function setIssues(array $issues) {
     $this->issues = array_fuse($issues);
     return $this;
   }
 
   public function getIssues() {
     $issues = $this->issues;
 
     foreach ($this->getSubschemata() as $sub) {
       switch ($sub->getStatus()) {
         case self::STATUS_NOTE:
           $issues[self::ISSUE_SUBNOTE] = self::ISSUE_SUBNOTE;
           break;
         case self::STATUS_WARN:
           $issues[self::ISSUE_SUBWARN] = self::ISSUE_SUBWARN;
           break;
         case self::STATUS_FAIL:
           $issues[self::ISSUE_SUBFAIL] = self::ISSUE_SUBFAIL;
           break;
       }
     }
 
     return $issues;
   }
 
   public function getLocalIssues() {
     return $this->issues;
   }
 
   public function hasIssue($issue) {
     return (bool)idx($this->getIssues(), $issue);
   }
 
   public function getAllIssues() {
     $issues = $this->getIssues();
     foreach ($this->getSubschemata() as $sub) {
       $issues += $sub->getAllIssues();
     }
     return $issues;
   }
 
   public function getStatus() {
     $status = self::STATUS_OKAY;
     foreach ($this->getAllIssues() as $issue) {
       $issue_status = self::getIssueStatus($issue);
       $status = self::getStrongestStatus($status, $issue_status);
     }
     return $status;
   }
 
   public static function getIssueName($issue) {
     switch ($issue) {
       case self::ISSUE_MISSING:
         return pht('Missing');
       case self::ISSUE_MISSINGKEY:
         return pht('Missing Key');
       case self::ISSUE_SURPLUS:
         return pht('Surplus');
       case self::ISSUE_SURPLUSKEY:
         return pht('Surplus Key');
       case self::ISSUE_CHARSET:
         return pht('Better Character Set Available');
       case self::ISSUE_COLLATION:
         return pht('Better Collation Available');
       case self::ISSUE_COLUMNTYPE:
         return pht('Wrong Column Type');
       case self::ISSUE_NULLABLE:
         return pht('Wrong Nullable Setting');
       case self::ISSUE_KEYCOLUMNS:
         return pht('Key on Wrong Columns');
       case self::ISSUE_UNIQUE:
         return pht('Key has Wrong Uniqueness');
       case self::ISSUE_SUBNOTE:
         return pht('Subschemata Have Notices');
       case self::ISSUE_SUBWARN:
         return pht('Subschemata Have Warnings');
       case self::ISSUE_SUBFAIL:
         return pht('Subschemata Have Failures');
       default:
         throw new Exception(pht('Unknown schema issue "%s"!', $issue));
     }
   }
 
   public static function getIssueDescription($issue) {
     switch ($issue) {
       case self::ISSUE_MISSING:
         return pht('This schema is expected to exist, but does not.');
       case self::ISSUE_MISSINGKEY:
         return pht('This key is expected to exist, but does not.');
       case self::ISSUE_SURPLUS:
         return pht('This schema is not expected to exist.');
       case self::ISSUE_SURPLUSKEY:
         return pht('This key is not expected to exist.');
       case self::ISSUE_CHARSET:
         return pht('This schema can use a better character set.');
       case self::ISSUE_COLLATION:
         return pht('This schema can use a better collation.');
       case self::ISSUE_COLUMNTYPE:
         return pht('This schema can use a better column type.');
       case self::ISSUE_NULLABLE:
         return pht('This schema has the wrong nullable setting.');
       case self::ISSUE_KEYCOLUMNS:
         return pht('This schema is on the wrong columns.');
       case self::ISSUE_UNIQUE:
         return pht('This key has the wrong uniqueness setting.');
       case self::ISSUE_SUBNOTE:
         return pht('Subschemata have setup notices.');
       case self::ISSUE_SUBWARN:
         return pht('Subschemata have setup warnings.');
       case self::ISSUE_SUBFAIL:
         return pht('Subschemata have setup failures.');
       default:
         throw new Exception(pht('Unknown schema issue "%s"!', $issue));
     }
   }
 
   public static function getIssueStatus($issue) {
     switch ($issue) {
       case self::ISSUE_MISSING:
       case self::ISSUE_SURPLUS:
       case self::ISSUE_SUBFAIL:
+      case self::ISSUE_NULLABLE:
         return self::STATUS_FAIL;
       case self::ISSUE_SUBWARN:
       case self::ISSUE_COLUMNTYPE:
-      case self::ISSUE_NULLABLE:
         return self::STATUS_WARN;
       case self::ISSUE_SUBNOTE:
       case self::ISSUE_CHARSET:
       case self::ISSUE_COLLATION:
       case self::ISSUE_MISSINGKEY:
       case self::ISSUE_SURPLUSKEY:
       case self::ISSUE_UNIQUE:
       case self::ISSUE_KEYCOLUMNS:
         return self::STATUS_NOTE;
       default:
         throw new Exception(pht('Unknown schema issue "%s"!', $issue));
     }
   }
 
   public static function getStatusSeverity($status) {
     switch ($status) {
       case self::STATUS_FAIL:
         return 3;
       case self::STATUS_WARN:
         return 2;
       case self::STATUS_NOTE:
         return 1;
       case self::STATUS_OKAY:
         return 0;
       default:
         throw new Exception(pht('Unknown schema status "%s"!', $status));
     }
   }
 
   public static function getStrongestStatus($u, $v) {
     $u_sev = self::getStatusSeverity($u);
     $v_sev = self::getStatusSeverity($v);
 
     if ($u_sev >= $v_sev) {
       return $u;
     } else {
       return $v;
     }
   }
 
 
 }
diff --git a/src/applications/differential/storage/DifferentialChangeset.php b/src/applications/differential/storage/DifferentialChangeset.php
index 5ae22d8a2c..8e5c3af6b2 100644
--- a/src/applications/differential/storage/DifferentialChangeset.php
+++ b/src/applications/differential/storage/DifferentialChangeset.php
@@ -1,225 +1,233 @@
 <?php
 
 final class DifferentialChangeset extends DifferentialDAO
   implements PhabricatorPolicyInterface {
 
   protected $diffID;
   protected $oldFile;
   protected $filename;
   protected $awayPaths;
   protected $changeType;
   protected $fileType;
   protected $metadata;
   protected $oldProperties;
   protected $newProperties;
   protected $addLines;
   protected $delLines;
 
   private $unsavedHunks = array();
   private $hunks = self::ATTACHABLE;
   private $diff = self::ATTACHABLE;
 
   const TABLE_CACHE = 'differential_changeset_parse_cache';
 
   protected function getConfiguration() {
     return array(
       self::CONFIG_SERIALIZATION => array(
         'metadata'      => self::SERIALIZATION_JSON,
         'oldProperties' => self::SERIALIZATION_JSON,
         'newProperties' => self::SERIALIZATION_JSON,
         'awayPaths'     => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'oldFile' => 'text255?',
         'filename' => 'text255',
         'changeType' => 'uint32',
         'fileType' => 'uint32',
         'addLines' => 'uint32',
         'delLines' => 'uint32',
+
+        // T6203/NULLABILITY
+        // These should all be non-nullable, and store reasonable default
+        // JSON values if empty.
+        'awayPaths' => 'text?',
+        'metadata' => 'text?',
+        'oldProperties' => 'text?',
+        'newProperties' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'diffID' => array(
           'columns' => array('diffID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function getAffectedLineCount() {
     return $this->getAddLines() + $this->getDelLines();
   }
 
   public function attachHunks(array $hunks) {
     assert_instances_of($hunks, 'DifferentialHunk');
     $this->hunks = $hunks;
     return $this;
   }
 
   public function getHunks() {
     return $this->assertAttached($this->hunks);
   }
 
   public function getDisplayFilename() {
     $name = $this->getFilename();
     if ($this->getFileType() == DifferentialChangeType::FILE_DIRECTORY) {
       $name .= '/';
     }
     return $name;
   }
 
   public function addUnsavedHunk(DifferentialHunk $hunk) {
     if ($this->hunks === self::ATTACHABLE) {
       $this->hunks = array();
     }
     $this->hunks[] = $hunk;
     $this->unsavedHunks[] = $hunk;
     return $this;
   }
 
   public function save() {
     $this->openTransaction();
       $ret = parent::save();
       foreach ($this->unsavedHunks as $hunk) {
         $hunk->setChangesetID($this->getID());
         $hunk->save();
       }
     $this->saveTransaction();
     return $ret;
   }
 
   public function delete() {
     $this->openTransaction();
 
       $legacy_hunks = id(new DifferentialHunkLegacy())->loadAllWhere(
         'changesetID = %d',
         $this->getID());
       foreach ($legacy_hunks as $legacy_hunk) {
         $legacy_hunk->delete();
       }
 
       $modern_hunks = id(new DifferentialHunkModern())->loadAllWhere(
         'changesetID = %d',
         $this->getID());
       foreach ($modern_hunks as $modern_hunk) {
         $modern_hunk->delete();
       }
 
       $this->unsavedHunks = array();
 
       queryfx(
         $this->establishConnection('w'),
         'DELETE FROM %T WHERE id = %d',
         self::TABLE_CACHE,
         $this->getID());
 
       $ret = parent::delete();
     $this->saveTransaction();
     return $ret;
   }
 
   public function getSortKey() {
     $sort_key = $this->getFilename();
     // Sort files with ".h" in them first, so headers (.h, .hpp) come before
     // implementations (.c, .cpp, .cs).
     $sort_key = str_replace('.h', '.!h', $sort_key);
     return $sort_key;
   }
 
   public function makeNewFile() {
     $file = mpull($this->getHunks(), 'makeNewFile');
     return implode('', $file);
   }
 
   public function makeOldFile() {
     $file = mpull($this->getHunks(), 'makeOldFile');
     return implode('', $file);
   }
 
   public function makeChangesWithContext($num_lines = 3) {
     $with_context = array();
     foreach ($this->getHunks() as $hunk) {
       $context = array();
       $changes = explode("\n", $hunk->getChanges());
       foreach ($changes as $l => $line) {
         $type = substr($line, 0, 1);
         if ($type == '+' || $type == '-') {
           $context += array_fill($l - $num_lines, 2 * $num_lines + 1, true);
         }
       }
       $with_context[] = array_intersect_key($changes, $context);
     }
     return array_mergev($with_context);
   }
 
   public function getAnchorName() {
     return substr(md5($this->getFilename()), 0, 8);
   }
 
   public function getAbsoluteRepositoryPath(
     PhabricatorRepository $repository = null,
     DifferentialDiff $diff = null) {
 
     $base = '/';
     if ($diff && $diff->getSourceControlPath()) {
       $base = id(new PhutilURI($diff->getSourceControlPath()))->getPath();
     }
 
     $path = $this->getFilename();
     $path = rtrim($base, '/').'/'.ltrim($path, '/');
 
     $svn = PhabricatorRepositoryType::REPOSITORY_TYPE_SVN;
     if ($repository && $repository->getVersionControlSystem() == $svn) {
       $prefix = $repository->getDetail('remote-uri');
       $prefix = id(new PhutilURI($prefix))->getPath();
       if (!strncmp($path, $prefix, strlen($prefix))) {
         $path = substr($path, strlen($prefix));
       }
       $path = '/'.ltrim($path, '/');
     }
 
     return $path;
   }
 
   public function getWhitespaceMatters() {
     $config = PhabricatorEnv::getEnvConfig('differential.whitespace-matters');
     foreach ($config as $regexp) {
       if (preg_match($regexp, $this->getFilename())) {
         return true;
       }
     }
 
     return false;
   }
 
   public function attachDiff(DifferentialDiff $diff) {
     $this->diff = $diff;
     return $this;
   }
 
   public function getDiff() {
     return $this->assertAttached($this->diff);
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getDiff()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getDiff()->hasAutomaticCapability($capability, $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return null;
   }
 
 }
diff --git a/src/applications/differential/storage/DifferentialDiff.php b/src/applications/differential/storage/DifferentialDiff.php
index 7828510f80..7e74ad0929 100644
--- a/src/applications/differential/storage/DifferentialDiff.php
+++ b/src/applications/differential/storage/DifferentialDiff.php
@@ -1,442 +1,446 @@
 <?php
 
 final class DifferentialDiff
   extends DifferentialDAO
   implements
     PhabricatorPolicyInterface,
     HarbormasterBuildableInterface,
     PhabricatorApplicationTransactionInterface,
     PhabricatorDestructibleInterface {
 
   protected $revisionID;
   protected $authorPHID;
   protected $repositoryPHID;
 
   protected $sourceMachine;
   protected $sourcePath;
 
   protected $sourceControlSystem;
   protected $sourceControlBaseRevision;
   protected $sourceControlPath;
 
   protected $lintStatus;
   protected $unitStatus;
 
   protected $lineCount;
 
   protected $branch;
   protected $bookmark;
 
   protected $arcanistProjectPHID;
   protected $creationMethod;
   protected $repositoryUUID;
 
   protected $description;
 
   private $unsavedChangesets = array();
   private $changesets = self::ATTACHABLE;
   private $arcanistProject = self::ATTACHABLE;
   private $revision = self::ATTACHABLE;
   private $properties = array();
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
         'revisionID' => 'id?',
         'authorPHID' => 'phid?',
         'repositoryPHID' => 'phid?',
         'sourceMachine' => 'text255?',
         'sourcePath' => 'text255?',
         'sourceControlSystem' => 'text64?',
         'sourceControlBaseRevision' => 'text255?',
         'sourceControlPath' => 'text255?',
         'lintStatus' => 'uint32',
         'unitStatus' => 'uint32',
         'lineCount' => 'uint32',
         'branch' => 'text255?',
         'bookmark' => 'text255?',
         'arcanistProjectPHID' => 'phid?',
-        'creationMethod' => 'text255',
-        'description' => 'text255',
         'repositoryUUID' => 'text64?',
+
+        // T6203/NULLABILITY
+        // These should be non-null; all diffs should have a creation method
+        // and the description should just be empty.
+        'creationMethod' => 'text255?',
+        'description' => 'text255?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'revisionID' => array(
           'columns' => array('revisionID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       DifferentialDiffPHIDType::TYPECONST);
   }
 
   public function addUnsavedChangeset(DifferentialChangeset $changeset) {
     if ($this->changesets === null) {
       $this->changesets = array();
     }
     $this->unsavedChangesets[] = $changeset;
     $this->changesets[] = $changeset;
     return $this;
   }
 
   public function attachChangesets(array $changesets) {
     assert_instances_of($changesets, 'DifferentialChangeset');
     $this->changesets = $changesets;
     return $this;
   }
 
   public function getChangesets() {
     return $this->assertAttached($this->changesets);
   }
 
   public function loadChangesets() {
     if (!$this->getID()) {
       return array();
     }
     return id(new DifferentialChangeset())->loadAllWhere(
       'diffID = %d',
       $this->getID());
   }
 
   public function attachArcanistProject(
     PhabricatorRepositoryArcanistProject $project = null) {
     $this->arcanistProject = $project;
     return $this;
   }
 
   public function getArcanistProject() {
     return $this->assertAttached($this->arcanistProject);
   }
 
   public function getArcanistProjectName() {
     $name = '';
     if ($this->arcanistProject) {
       $project = $this->getArcanistProject();
       $name = $project->getName();
     }
     return $name;
   }
 
   public function save() {
     $this->openTransaction();
       $ret = parent::save();
       foreach ($this->unsavedChangesets as $changeset) {
         $changeset->setDiffID($this->getID());
         $changeset->save();
       }
     $this->saveTransaction();
     return $ret;
   }
 
   public static function newFromRawChanges(array $changes) {
     assert_instances_of($changes, 'ArcanistDiffChange');
     $diff = new DifferentialDiff();
 
     // There may not be any changes; initialize the changesets list so that
     // we don't throw later when accessing it.
     $diff->attachChangesets(array());
 
     $lines = 0;
     foreach ($changes as $change) {
       if ($change->getType() == ArcanistDiffChangeType::TYPE_MESSAGE) {
         // If a user pastes a diff into Differential which includes a commit
         // message (e.g., they ran `git show` to generate it), discard that
         // change when constructing a DifferentialDiff.
         continue;
       }
 
       $changeset = new DifferentialChangeset();
       $add_lines = 0;
       $del_lines = 0;
       $first_line = PHP_INT_MAX;
       $hunks = $change->getHunks();
       if ($hunks) {
         foreach ($hunks as $hunk) {
           $dhunk = new DifferentialHunkModern();
           $dhunk->setOldOffset($hunk->getOldOffset());
           $dhunk->setOldLen($hunk->getOldLength());
           $dhunk->setNewOffset($hunk->getNewOffset());
           $dhunk->setNewLen($hunk->getNewLength());
           $dhunk->setChanges($hunk->getCorpus());
           $changeset->addUnsavedHunk($dhunk);
           $add_lines += $hunk->getAddLines();
           $del_lines += $hunk->getDelLines();
           $added_lines = $hunk->getChangedLines('new');
           if ($added_lines) {
             $first_line = min($first_line, head_key($added_lines));
           }
         }
         $lines += $add_lines + $del_lines;
       } else {
         // This happens when you add empty files.
         $changeset->attachHunks(array());
       }
 
       $metadata = $change->getAllMetadata();
       if ($first_line != PHP_INT_MAX) {
         $metadata['line:first'] = $first_line;
       }
 
       $changeset->setOldFile($change->getOldPath());
       $changeset->setFilename($change->getCurrentPath());
       $changeset->setChangeType($change->getType());
 
       $changeset->setFileType($change->getFileType());
       $changeset->setMetadata($metadata);
       $changeset->setOldProperties($change->getOldProperties());
       $changeset->setNewProperties($change->getNewProperties());
       $changeset->setAwayPaths($change->getAwayPaths());
       $changeset->setAddLines($add_lines);
       $changeset->setDelLines($del_lines);
 
       $diff->addUnsavedChangeset($changeset);
     }
     $diff->setLineCount($lines);
 
     $parser = new DifferentialChangesetParser();
     $changesets = $parser->detectCopiedCode(
       $diff->getChangesets(),
       $min_width = 30,
       $min_lines = 3);
     $diff->attachChangesets($changesets);
 
     return $diff;
   }
 
 
   public function getDiffDict() {
     $dict = array(
       'id' => $this->getID(),
       'revisionID' => $this->getRevisionID(),
       'dateCreated' => $this->getDateCreated(),
       'dateModified' => $this->getDateModified(),
       'sourceControlBaseRevision' => $this->getSourceControlBaseRevision(),
       'sourceControlPath' => $this->getSourceControlPath(),
       'sourceControlSystem' => $this->getSourceControlSystem(),
       'branch' => $this->getBranch(),
       'bookmark' => $this->getBookmark(),
       'creationMethod' => $this->getCreationMethod(),
       'description' => $this->getDescription(),
       'unitStatus' => $this->getUnitStatus(),
       'lintStatus' => $this->getLintStatus(),
       'changes' => array(),
       'properties' => array(),
       'projectName' => $this->getArcanistProjectName()
     );
 
     $dict['changes'] = $this->buildChangesList();
 
     $properties = id(new DifferentialDiffProperty())->loadAllWhere(
       'diffID = %d',
       $this->getID());
     foreach ($properties as $property) {
       $dict['properties'][$property->getName()] = $property->getData();
 
       if ($property->getName() == 'local:commits') {
         foreach ($property->getData() as $commit) {
           $dict['authorName'] = $commit['author'];
           $dict['authorEmail'] = idx($commit, 'authorEmail');
           break;
         }
       }
     }
 
     return $dict;
   }
 
   public function buildChangesList() {
     $changes = array();
     foreach ($this->getChangesets() as $changeset) {
       $hunks = array();
       foreach ($changeset->getHunks() as $hunk) {
         $hunks[] = array(
           'oldOffset' => $hunk->getOldOffset(),
           'newOffset' => $hunk->getNewOffset(),
           'oldLength' => $hunk->getOldLen(),
           'newLength' => $hunk->getNewLen(),
           'addLines'  => null,
           'delLines'  => null,
           'isMissingOldNewline' => null,
           'isMissingNewNewline' => null,
           'corpus'    => $hunk->getChanges(),
         );
       }
       $change = array(
         'id'            => $changeset->getID(),
         'metadata'      => $changeset->getMetadata(),
         'oldPath'       => $changeset->getOldFile(),
         'currentPath'   => $changeset->getFilename(),
         'awayPaths'     => $changeset->getAwayPaths(),
         'oldProperties' => $changeset->getOldProperties(),
         'newProperties' => $changeset->getNewProperties(),
         'type'          => $changeset->getChangeType(),
         'fileType'      => $changeset->getFileType(),
         'commitHash'    => null,
         'addLines'      => $changeset->getAddLines(),
         'delLines'      => $changeset->getDelLines(),
         'hunks'         => $hunks,
       );
       $changes[] = $change;
     }
     return $changes;
   }
 
   public function getRevision() {
     return $this->assertAttached($this->revision);
   }
 
   public function attachRevision(DifferentialRevision $revision = null) {
     $this->revision = $revision;
     return $this;
   }
 
   public function attachProperty($key, $value) {
     $this->properties[$key] = $value;
     return $this;
   }
 
   public function getProperty($key) {
     return $this->assertAttachedKey($this->properties, $key);
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     if ($this->getRevision()) {
       return $this->getRevision()->getPolicy($capability);
     }
 
     return PhabricatorPolicies::POLICY_USER;
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     if ($this->getRevision()) {
       return $this->getRevision()->hasAutomaticCapability($capability, $viewer);
     }
 
     return false;
   }
 
   public function describeAutomaticCapability($capability) {
     if ($this->getRevision()) {
       return pht(
         'This diff is attached to a revision, and inherits its policies.');
     }
     return null;
   }
 
 
 
 /* -(  HarbormasterBuildableInterface  )------------------------------------- */
 
 
   public function getHarbormasterBuildablePHID() {
     return $this->getPHID();
   }
 
   public function getHarbormasterContainerPHID() {
     if ($this->getRevisionID()) {
       $revision = id(new DifferentialRevision())->load($this->getRevisionID());
       if ($revision) {
         return $revision->getPHID();
       }
     }
 
     return null;
   }
 
   public function getBuildVariables() {
     $results = array();
 
     $results['buildable.diff'] = $this->getID();
     $revision = $this->getRevision();
     $results['buildable.revision'] = $revision->getID();
     $repo = $revision->getRepository();
 
     if ($repo) {
       $results['repository.callsign'] = $repo->getCallsign();
       $results['repository.vcs'] = $repo->getVersionControlSystem();
       $results['repository.uri'] = $repo->getPublicCloneURI();
     }
 
     return $results;
   }
 
   public function getAvailableBuildVariables() {
     return array(
       'buildable.diff' =>
         pht('The differential diff ID, if applicable.'),
       'buildable.revision' =>
         pht('The differential revision ID, if applicable.'),
       'repository.callsign' =>
         pht('The callsign of the repository in Phabricator.'),
       'repository.vcs' =>
         pht('The version control system, either "svn", "hg" or "git".'),
       'repository.uri' =>
         pht('The URI to clone or checkout the repository from.'),
     );
   }
 
 
 /* -(  PhabricatorApplicationTransactionInterface  )------------------------- */
 
 
   public function getApplicationTransactionEditor() {
     if (!$this->getRevisionID()) {
       return null;
     }
     return $this->getRevision()->getApplicationTransactionEditor();
   }
 
 
   public function getApplicationTransactionObject() {
     if (!$this->getRevisionID()) {
       return null;
     }
     return $this->getRevision();
   }
 
   public function getApplicationTransactionTemplate() {
     if (!$this->getRevisionID()) {
       return null;
     }
     return $this->getRevision()->getApplicationTransactionTemplate();
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
       $this->delete();
 
       foreach ($this->loadChangesets() as $changeset) {
         $changeset->delete();
       }
 
       $properties = id(new DifferentialDiffProperty())->loadAllWhere(
         'diffID = %d',
         $this->getID());
       foreach ($properties as $prop) {
         $prop->delete();
       }
 
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/differential/storage/DifferentialRevision.php b/src/applications/differential/storage/DifferentialRevision.php
index c8b3fa17af..f33ba47526 100644
--- a/src/applications/differential/storage/DifferentialRevision.php
+++ b/src/applications/differential/storage/DifferentialRevision.php
@@ -1,527 +1,527 @@
 <?php
 
 final class DifferentialRevision extends DifferentialDAO
   implements
     PhabricatorTokenReceiverInterface,
     PhabricatorPolicyInterface,
     PhabricatorFlaggableInterface,
     PhrequentTrackableInterface,
     HarbormasterBuildableInterface,
     PhabricatorSubscribableInterface,
     PhabricatorCustomFieldInterface,
     PhabricatorApplicationTransactionInterface,
     PhabricatorMentionableInterface,
     PhabricatorDestructibleInterface,
     PhabricatorProjectInterface {
 
   protected $title = '';
   protected $originalTitle;
   protected $status;
 
   protected $summary = '';
   protected $testPlan = '';
 
   protected $authorPHID;
   protected $lastReviewerPHID;
 
   protected $lineCount = 0;
   protected $attached = array();
 
   protected $mailKey;
   protected $branchName;
   protected $arcanistProjectPHID;
   protected $repositoryPHID;
   protected $viewPolicy = PhabricatorPolicies::POLICY_USER;
   protected $editPolicy = PhabricatorPolicies::POLICY_USER;
 
   private $relationships = self::ATTACHABLE;
   private $commits = self::ATTACHABLE;
   private $activeDiff = self::ATTACHABLE;
   private $diffIDs = self::ATTACHABLE;
   private $hashes = self::ATTACHABLE;
   private $repository = self::ATTACHABLE;
 
   private $reviewerStatus = self::ATTACHABLE;
   private $customFields = self::ATTACHABLE;
   private $drafts = array();
   private $flags = array();
 
   const TABLE_COMMIT          = 'differential_commit';
 
   const RELATION_REVIEWER     = 'revw';
   const RELATION_SUBSCRIBED   = 'subd';
 
   public static function initializeNewRevision(PhabricatorUser $actor) {
     $app = id(new PhabricatorApplicationQuery())
       ->setViewer($actor)
       ->withClasses(array('PhabricatorDifferentialApplication'))
       ->executeOne();
 
     $view_policy = $app->getPolicy(
       DifferentialDefaultViewCapability::CAPABILITY);
 
     return id(new DifferentialRevision())
       ->setViewPolicy($view_policy)
       ->setAuthorPHID($actor->getPHID())
       ->attachRelationships(array())
       ->setStatus(ArcanistDifferentialRevisionStatus::NEEDS_REVIEW);
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'attached'      => self::SERIALIZATION_JSON,
         'unsubscribed'  => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'title' => 'text255',
         'originalTitle' => 'text255',
         'status' => 'text32',
         'summary' => 'text',
         'testPlan' => 'text',
         'authorPHID' => 'phid?',
         'lastReviewerPHID' => 'phid?',
         'lineCount' => 'uint32?',
         'mailKey' => 'bytes40',
-        'branchName' => 'text255',
+        'branchName' => 'text255?',
         'arcanistProjectPHID' => 'phid?',
         'repositoryPHID' => 'phid?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID', 'status'),
         ),
         'repositoryPHID' => array(
           'columns' => array('repositoryPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function getMonogram() {
     $id = $this->getID();
     return "D{$id}";
   }
 
   public function setTitle($title) {
     $this->title = $title;
     if (!$this->getID()) {
       $this->originalTitle = $title;
     }
     return $this;
   }
 
   public function loadIDsByCommitPHIDs($phids) {
     if (!$phids) {
       return array();
     }
     $revision_ids = queryfx_all(
       $this->establishConnection('r'),
       'SELECT * FROM %T WHERE commitPHID IN (%Ls)',
       self::TABLE_COMMIT,
       $phids);
     return ipull($revision_ids, 'revisionID', 'commitPHID');
   }
 
   public function loadCommitPHIDs() {
     if (!$this->getID()) {
       return ($this->commits = array());
     }
 
     $commits = queryfx_all(
       $this->establishConnection('r'),
       'SELECT commitPHID FROM %T WHERE revisionID = %d',
       self::TABLE_COMMIT,
       $this->getID());
     $commits = ipull($commits, 'commitPHID');
 
     return ($this->commits = $commits);
   }
 
   public function getCommitPHIDs() {
     return $this->assertAttached($this->commits);
   }
 
   public function getActiveDiff() {
     // TODO: Because it's currently technically possible to create a revision
     // without an associated diff, we allow an attached-but-null active diff.
     // It would be good to get rid of this once we make diff-attaching
     // transactional.
 
     return $this->assertAttached($this->activeDiff);
   }
 
   public function attachActiveDiff($diff) {
     $this->activeDiff = $diff;
     return $this;
   }
 
   public function getDiffIDs() {
     return $this->assertAttached($this->diffIDs);
   }
 
   public function attachDiffIDs(array $ids) {
     rsort($ids);
     $this->diffIDs = array_values($ids);
     return $this;
   }
 
   public function attachCommitPHIDs(array $phids) {
     $this->commits = array_values($phids);
     return $this;
   }
 
   public function getAttachedPHIDs($type) {
     return array_keys(idx($this->attached, $type, array()));
   }
 
   public function setAttachedPHIDs($type, array $phids) {
     $this->attached[$type] = array_fill_keys($phids, array());
     return $this;
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       DifferentialRevisionPHIDType::TYPECONST);
   }
 
   public function loadActiveDiff() {
     return id(new DifferentialDiff())->loadOneWhere(
       'revisionID = %d ORDER BY id DESC LIMIT 1',
       $this->getID());
   }
 
   public function save() {
     if (!$this->getMailKey()) {
       $this->mailKey = Filesystem::readRandomCharacters(40);
     }
     return parent::save();
   }
 
   public function loadRelationships() {
     if (!$this->getID()) {
       $this->relationships = array();
       return;
     }
 
     $data = array();
 
     $subscriber_phids = PhabricatorEdgeQuery::loadDestinationPHIDs(
       $this->getPHID(),
       PhabricatorEdgeConfig::TYPE_OBJECT_HAS_SUBSCRIBER);
     $subscriber_phids = array_reverse($subscriber_phids);
     foreach ($subscriber_phids as $phid) {
       $data[] = array(
         'relation' => self::RELATION_SUBSCRIBED,
         'objectPHID' => $phid,
         'reasonPHID' => null,
       );
     }
 
     $reviewer_phids = PhabricatorEdgeQuery::loadDestinationPHIDs(
       $this->getPHID(),
       PhabricatorEdgeConfig::TYPE_DREV_HAS_REVIEWER);
     $reviewer_phids = array_reverse($reviewer_phids);
     foreach ($reviewer_phids as $phid) {
       $data[] = array(
         'relation' => self::RELATION_REVIEWER,
         'objectPHID' => $phid,
         'reasonPHID' => null,
       );
     }
 
     return $this->attachRelationships($data);
   }
 
   public function attachRelationships(array $relationships) {
     $this->relationships = igroup($relationships, 'relation');
     return $this;
   }
 
   public function getReviewers() {
     return $this->getRelatedPHIDs(self::RELATION_REVIEWER);
   }
 
   public function getCCPHIDs() {
     return $this->getRelatedPHIDs(self::RELATION_SUBSCRIBED);
   }
 
   private function getRelatedPHIDs($relation) {
     $this->assertAttached($this->relationships);
 
     return ipull($this->getRawRelations($relation), 'objectPHID');
   }
 
   public function getRawRelations($relation) {
     return idx($this->relationships, $relation, array());
   }
 
   public function getPrimaryReviewer() {
     $reviewers = $this->getReviewers();
     $last = $this->lastReviewerPHID;
     if (!$last || !in_array($last, $reviewers)) {
       return head($this->getReviewers());
     }
     return $last;
   }
 
   public function getHashes() {
     return $this->assertAttached($this->hashes);
   }
 
   public function attachHashes(array $hashes) {
     $this->hashes = $hashes;
     return $this;
   }
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getViewPolicy();
       case PhabricatorPolicyCapability::CAN_EDIT:
         return $this->getEditPolicy();
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $user) {
     // A revision's author (which effectively means "owner" after we added
     // commandeering) can always view and edit it.
     $author_phid = $this->getAuthorPHID();
     if ($author_phid) {
       if ($user->getPHID() == $author_phid) {
         return true;
       }
     }
 
     return false;
   }
 
   public function describeAutomaticCapability($capability) {
     $description = array(
       pht('The owner of a revision can always view and edit it.'),
     );
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         $description[] = pht(
           "A revision's reviewers can always view it.");
         $description[] = pht(
           'If a revision belongs to a repository, other users must be able '.
           'to view the repository in order to view the revision.');
         break;
     }
 
     return $description;
   }
 
   public function getUsersToNotifyOfTokenGiven() {
     return array(
       $this->getAuthorPHID(),
     );
   }
 
   public function getReviewerStatus() {
     return $this->assertAttached($this->reviewerStatus);
   }
 
   public function attachReviewerStatus(array $reviewers) {
     assert_instances_of($reviewers, 'DifferentialReviewer');
 
     $this->reviewerStatus = $reviewers;
     return $this;
   }
 
   public function getRepository() {
     return $this->assertAttached($this->repository);
   }
 
   public function attachRepository(PhabricatorRepository $repository = null) {
     $this->repository = $repository;
     return $this;
   }
 
   public function isClosed() {
     return DifferentialRevisionStatus::isClosedStatus($this->getStatus());
   }
 
   public function getFlag(PhabricatorUser $viewer) {
     return $this->assertAttachedKey($this->flags, $viewer->getPHID());
   }
 
   public function attachFlag(
     PhabricatorUser $viewer,
     PhabricatorFlag $flag = null) {
     $this->flags[$viewer->getPHID()] = $flag;
     return $this;
   }
 
   public function getDrafts(PhabricatorUser $viewer) {
     return $this->assertAttachedKey($this->drafts, $viewer->getPHID());
   }
 
   public function attachDrafts(PhabricatorUser $viewer, array $drafts) {
     $this->drafts[$viewer->getPHID()] = $drafts;
     return $this;
   }
 
 
 /* -(  HarbormasterBuildableInterface  )------------------------------------- */
 
 
   public function getHarbormasterBuildablePHID() {
     return $this->loadActiveDiff()->getPHID();
   }
 
   public function getHarbormasterContainerPHID() {
     return $this->getPHID();
   }
 
   public function getBuildVariables() {
     return array();
   }
 
   public function getAvailableBuildVariables() {
     return array();
   }
 
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
 
   public function isAutomaticallySubscribed($phid) {
     if ($phid == $this->getAuthorPHID()) {
       return true;
     }
 
     // TODO: This only happens when adding or removing CCs, and is safe from a
     // policy perspective, but the subscription pathway should have some
     // opportunity to load this data properly. For now, this is the only case
     // where implicit subscription is not an intrinsic property of the object.
     if ($this->reviewerStatus == self::ATTACHABLE) {
       $reviewers = id(new DifferentialRevisionQuery())
         ->setViewer(PhabricatorUser::getOmnipotentUser())
         ->withPHIDs(array($this->getPHID()))
         ->needReviewerStatus(true)
         ->executeOne()
         ->getReviewerStatus();
     } else {
       $reviewers = $this->getReviewerStatus();
     }
 
     foreach ($reviewers as $reviewer) {
       if ($reviewer->getReviewerPHID() == $phid) {
         return true;
       }
     }
 
     return false;
   }
 
   public function shouldShowSubscribersProperty() {
     return true;
   }
 
   public function shouldAllowSubscription($phid) {
     return true;
   }
 
 
 /* -(  PhabricatorCustomFieldInterface  )------------------------------------ */
 
 
   public function getCustomFieldSpecificationForRole($role) {
     return PhabricatorEnv::getEnvConfig('differential.fields');
   }
 
   public function getCustomFieldBaseClass() {
     return 'DifferentialCustomField';
   }
 
   public function getCustomFields() {
     return $this->assertAttached($this->customFields);
   }
 
   public function attachCustomFields(PhabricatorCustomFieldAttachment $fields) {
     $this->customFields = $fields;
     return $this;
   }
 
 
 /* -(  PhabricatorApplicationTransactionInterface  )------------------------- */
 
 
   public function getApplicationTransactionEditor() {
     return new DifferentialTransactionEditor();
   }
 
   public function getApplicationTransactionObject() {
     return $this;
   }
 
   public function getApplicationTransactionTemplate() {
     return new DifferentialTransaction();
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
       $diffs = id(new DifferentialDiffQuery())
         ->setViewer(PhabricatorUser::getOmnipotentUser())
         ->withRevisionIDs(array($this->getID()))
         ->execute();
       foreach ($diffs as $diff) {
         $engine->destroyObject($diff);
       }
 
       $conn_w = $this->establishConnection('w');
 
       queryfx(
         $conn_w,
         'DELETE FROM %T WHERE revisionID = %d',
         self::TABLE_COMMIT,
         $this->getID());
 
       try {
         $inlines = id(new DifferentialInlineCommentQuery())
           ->withRevisionIDs(array($this->getID()))
           ->execute();
         foreach ($inlines as $inline) {
           $inline->delete();
         }
       } catch (PhabricatorEmptyQueryException $ex) {
         // TODO: There's still some funky legacy wrapping going on here, and
         // we might catch a raw query exception.
       }
 
       // we have to do paths a little differentally as they do not have
       // an id or phid column for delete() to act on
       $dummy_path = new DifferentialAffectedPath();
       queryfx(
         $conn_w,
         'DELETE FROM %T WHERE revisionID = %d',
         $dummy_path->getTableName(),
         $this->getID());
 
       $this->delete();
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/harbormaster/storage/HarbormasterObject.php b/src/applications/harbormaster/storage/HarbormasterObject.php
index f83b41a4b9..648c04c3dc 100644
--- a/src/applications/harbormaster/storage/HarbormasterObject.php
+++ b/src/applications/harbormaster/storage/HarbormasterObject.php
@@ -1,21 +1,21 @@
 <?php
 
 final class HarbormasterObject extends HarbormasterDAO {
 
   protected $name;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
-        'name' => 'text255',
+        'name' => 'text255?',
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       PhabricatorPHIDConstants::PHID_TYPE_TOBJ);
   }
 
 }
diff --git a/src/applications/harbormaster/storage/HarbormasterSchemaSpec.php b/src/applications/harbormaster/storage/HarbormasterSchemaSpec.php
index 11ca19c5c5..da3ab69d14 100644
--- a/src/applications/harbormaster/storage/HarbormasterSchemaSpec.php
+++ b/src/applications/harbormaster/storage/HarbormasterSchemaSpec.php
@@ -1,45 +1,49 @@
 <?php
 
 final class HarbormasterSchemaSpec extends PhabricatorConfigSchemaSpec {
 
   public function buildSchemata() {
     $this->buildLiskSchemata('HarbormasterDAO');
 
     $this->buildEdgeSchemata(new HarbormasterBuildable());
     $this->buildCounterSchema(new HarbormasterBuildable());
 
     $this->buildTransactionSchema(
       new HarbormasterBuildableTransaction());
 
     $this->buildTransactionSchema(
       new HarbormasterBuildTransaction());
 
     $this->buildTransactionSchema(
       new HarbormasterBuildPlanTransaction());
 
     $this->buildTransactionSchema(
       new HarbormasterBuildStepTransaction());
 
     $this->buildRawSchema(
       id(new HarbormasterBuildable())->getApplicationName(),
       'harbormaster_buildlogchunk',
       array(
         'id' => 'id',
         'logID' => 'id',
         'encoding' => 'text32',
-        'size' => 'uint32',
+
+        // T6203/NULLABILITY
+        // Both the type and nullability of this column are crazily wrong.
+        'size' => 'uint32?',
+
         'chunk' => 'bytes',
       ),
       array(
         'PRIMARY' => array(
           'columns' => array('id'),
           'unique' => true,
         ),
         'key_log' => array(
           'columns' => array('logID'),
         ),
       ));
 
   }
 
 }
diff --git a/src/applications/harbormaster/storage/build/HarbormasterBuildLog.php b/src/applications/harbormaster/storage/build/HarbormasterBuildLog.php
index 8ac71f6a25..6702a18fe7 100644
--- a/src/applications/harbormaster/storage/build/HarbormasterBuildLog.php
+++ b/src/applications/harbormaster/storage/build/HarbormasterBuildLog.php
@@ -1,204 +1,208 @@
 <?php
 
 final class HarbormasterBuildLog extends HarbormasterDAO
   implements PhabricatorPolicyInterface {
 
   protected $buildTargetPHID;
   protected $logSource;
   protected $logType;
   protected $duration;
   protected $live;
 
   private $buildTarget = self::ATTACHABLE;
 
   const CHUNK_BYTE_LIMIT = 102400;
 
   /**
    * The log is encoded as plain text.
    */
   const ENCODING_TEXT = 'text';
 
   public static function initializeNewBuildLog(
     HarbormasterBuildTarget $build_target) {
 
     return id(new HarbormasterBuildLog())
       ->setBuildTargetPHID($build_target->getPHID())
       ->setDuration(null)
       ->setLive(0);
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
-        'logSource' => 'text255',
-        'logType' => 'text255',
-        'duration' => 'uint32',
+        // T6203/NULLABILITY
+        // It seems like these should be non-nullable? All logs should have a
+        // source, etc.
+        'logSource' => 'text255?',
+        'logType' => 'text255?',
+        'duration' => 'uint32?',
+
         'live' => 'bool',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_buildtarget' => array(
           'columns' => array('buildTargetPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       HarbormasterBuildLogPHIDType::TYPECONST);
   }
 
   public function attachBuildTarget(HarbormasterBuildTarget $build_target) {
     $this->buildTarget = $build_target;
     return $this;
   }
 
   public function getBuildTarget() {
     return $this->assertAttached($this->buildTarget);
   }
 
   public function getName() {
     return pht('Build Log');
   }
 
   public function start() {
     if ($this->getLive()) {
       throw new Exception('Live logging has already started for this log.');
     }
 
     $this->setLive(1);
     $this->save();
 
     return time();
   }
 
   public function append($content) {
     if (!$this->getLive()) {
       throw new Exception('Start logging before appending data to the log.');
     }
     if (strlen($content) === 0) {
       return;
     }
 
     // If the length of the content is greater than the chunk size limit,
     // then we can never fit the content in a single record. We need to
     // split our content out and call append on it for as many parts as there
     // are to the content.
     if (strlen($content) > self::CHUNK_BYTE_LIMIT) {
       $current = $content;
       while (strlen($current) > self::CHUNK_BYTE_LIMIT) {
         $part = substr($current, 0, self::CHUNK_BYTE_LIMIT);
         $current = substr($current, self::CHUNK_BYTE_LIMIT);
         $this->append($part);
       }
       $this->append($current);
       return;
     }
 
     // Retrieve the size of last chunk from the DB for this log. If the
     // chunk is over 500K, then we need to create a new log entry.
     $conn = $this->establishConnection('w');
     $result = queryfx_all(
       $conn,
       'SELECT id, size, encoding '.
       'FROM harbormaster_buildlogchunk '.
       'WHERE logID = %d '.
       'ORDER BY id DESC '.
       'LIMIT 1',
       $this->getID());
     if (count($result) === 0 ||
       $result[0]['size'] + strlen($content) > self::CHUNK_BYTE_LIMIT ||
       $result[0]['encoding'] !== self::ENCODING_TEXT) {
 
       // We must insert a new chunk because the data we are appending
       // won't fit into the existing one, or we don't have any existing
       // chunk data.
       queryfx(
         $conn,
         'INSERT INTO harbormaster_buildlogchunk '.
         '(logID, encoding, size, chunk) '.
         'VALUES '.
         '(%d, %s, %d, %s)',
         $this->getID(),
         self::ENCODING_TEXT,
         strlen($content),
         $content);
     } else {
       // We have a resulting record that we can append our content onto.
       queryfx(
         $conn,
         'UPDATE harbormaster_buildlogchunk '.
         'SET chunk = CONCAT(chunk, %s), size = LENGTH(CONCAT(chunk, %s))'.
         'WHERE id = %d',
         $content,
         $content,
         $result[0]['id']);
     }
   }
 
   public function finalize($start = 0) {
     if (!$this->getLive()) {
       throw new Exception('Start logging before finalizing it.');
     }
 
     // TODO: Encode the log contents in a gzipped format.
     $this->reload();
     if ($start > 0) {
       $this->setDuration(time() - $start);
     }
     $this->setLive(0);
     $this->save();
   }
 
   public function getLogText() {
     // TODO: This won't cope very well if we're pulling like a 700MB
     // log file out of the DB. We should probably implement some sort
     // of optional limit parameter so that when we're rendering out only
     // 25 lines in the UI, we don't wastefully read in the whole log.
 
     // We have to read our content out of the database and stitch all of
     // the log data back together.
     $conn = $this->establishConnection('r');
     $result = queryfx_all(
       $conn,
       'SELECT chunk '.
       'FROM harbormaster_buildlogchunk '.
       'WHERE logID = %d '.
       'ORDER BY id ASC',
       $this->getID());
 
     $content = '';
     foreach ($result as $row) {
       $content .= $row['chunk'];
     }
     return $content;
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getBuildTarget()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getBuildTarget()->hasAutomaticCapability(
       $capability,
       $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return pht(
       'Users must be able to see a build target to view it\'s build log.');
   }
 
 
 }
diff --git a/src/applications/harbormaster/storage/build/HarbormasterBuildTarget.php b/src/applications/harbormaster/storage/build/HarbormasterBuildTarget.php
index c64db741ea..c043d137e2 100644
--- a/src/applications/harbormaster/storage/build/HarbormasterBuildTarget.php
+++ b/src/applications/harbormaster/storage/build/HarbormasterBuildTarget.php
@@ -1,262 +1,265 @@
 <?php
 
 final class HarbormasterBuildTarget extends HarbormasterDAO
   implements PhabricatorPolicyInterface {
 
   protected $name;
   protected $buildPHID;
   protected $buildStepPHID;
   protected $className;
   protected $details;
   protected $variables;
   protected $targetStatus;
   protected $dateStarted;
   protected $dateCompleted;
   protected $buildGeneration;
 
   const STATUS_PENDING = 'target/pending';
   const STATUS_BUILDING = 'target/building';
   const STATUS_WAITING = 'target/waiting';
   const STATUS_PASSED = 'target/passed';
   const STATUS_FAILED = 'target/failed';
   const STATUS_ABORTED = 'target/aborted';
 
   private $build = self::ATTACHABLE;
   private $buildStep = self::ATTACHABLE;
   private $implementation;
 
   public static function getBuildTargetStatusName($status) {
     switch ($status) {
       case self::STATUS_PENDING:
         return pht('Pending');
       case self::STATUS_BUILDING:
         return pht('Building');
       case self::STATUS_WAITING:
         return pht('Waiting for Message');
       case self::STATUS_PASSED:
         return pht('Passed');
       case self::STATUS_FAILED:
         return pht('Failed');
       case self::STATUS_ABORTED:
         return pht('Aborted');
       default:
         return pht('Unknown');
     }
   }
 
   public static function getBuildTargetStatusIcon($status) {
     switch ($status) {
       case self::STATUS_PENDING:
         return PHUIStatusItemView::ICON_OPEN;
       case self::STATUS_BUILDING:
       case self::STATUS_WAITING:
         return PHUIStatusItemView::ICON_RIGHT;
       case self::STATUS_PASSED:
         return PHUIStatusItemView::ICON_ACCEPT;
       case self::STATUS_FAILED:
         return PHUIStatusItemView::ICON_REJECT;
       case self::STATUS_ABORTED:
         return PHUIStatusItemView::ICON_MINUS;
       default:
         return PHUIStatusItemView::ICON_QUESTION;
     }
   }
 
   public static function getBuildTargetStatusColor($status) {
     switch ($status) {
       case self::STATUS_PENDING:
       case self::STATUS_BUILDING:
       case self::STATUS_WAITING:
         return 'blue';
       case self::STATUS_PASSED:
         return 'green';
       case self::STATUS_FAILED:
       case self::STATUS_ABORTED:
         return 'red';
       default:
         return 'bluegrey';
     }
   }
 
   public static function initializeNewBuildTarget(
     HarbormasterBuild $build,
     HarbormasterBuildStep $build_step,
     array $variables) {
     return id(new HarbormasterBuildTarget())
       ->setName($build_step->getName())
       ->setBuildPHID($build->getPHID())
       ->setBuildStepPHID($build_step->getPHID())
       ->setClassName($build_step->getClassName())
       ->setDetails($build_step->getDetails())
       ->setTargetStatus(self::STATUS_PENDING)
       ->setVariables($variables)
       ->setBuildGeneration($build->getBuildGeneration());
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'details' => self::SERIALIZATION_JSON,
         'variables' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'className' => 'text255',
         'targetStatus' => 'text64',
-        'name' => 'text255',
         'dateStarted' => 'epoch?',
         'dateCompleted' => 'epoch?',
         'buildGeneration' => 'uint32',
+
+        // T6203/NULLABILITY
+        // This should not be nullable.
+        'name' => 'text255?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_build' => array(
           'columns' => array('buildPHID', 'buildStepPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       HarbormasterBuildTargetPHIDType::TYPECONST);
   }
 
   public function attachBuild(HarbormasterBuild $build) {
     $this->build = $build;
     return $this;
   }
 
   public function getBuild() {
     return $this->assertAttached($this->build);
   }
 
   public function attachBuildStep(HarbormasterBuildStep $step = null) {
     $this->buildStep = $step;
     return $this;
   }
 
   public function getBuildStep() {
     return $this->assertAttached($this->buildStep);
   }
 
   public function getDetail($key, $default = null) {
     return idx($this->details, $key, $default);
   }
 
   public function setDetail($key, $value) {
     $this->details[$key] = $value;
     return $this;
   }
 
   public function getVariables() {
     return parent::getVariables() + $this->getBuildTargetVariables();
   }
 
   public function getVariable($key, $default = null) {
     return idx($this->variables, $key, $default);
   }
 
   public function setVariable($key, $value) {
     $this->variables[$key] = $value;
     return $this;
   }
 
   public function getImplementation() {
     if ($this->implementation === null) {
       $obj = HarbormasterBuildStepImplementation::requireImplementation(
         $this->className);
       $obj->loadSettings($this);
       $this->implementation = $obj;
     }
 
     return $this->implementation;
   }
 
   public function getName() {
     if (strlen($this->name)) {
       return $this->name;
     }
 
     try {
       return $this->getImplementation()->getName();
     } catch (Exception $e) {
       return $this->getClassName();
     }
   }
 
   private function getBuildTargetVariables() {
     return array(
       'target.phid' => $this->getPHID(),
     );
   }
 
 
 /* -(  Status  )------------------------------------------------------------- */
 
 
   public function isComplete() {
     switch ($this->getTargetStatus()) {
       case self::STATUS_PASSED:
       case self::STATUS_FAILED:
       case self::STATUS_ABORTED:
         return true;
     }
 
     return false;
   }
 
 
   public function isFailed() {
     switch ($this->getTargetStatus()) {
       case self::STATUS_FAILED:
         return true;
     }
 
     return false;
   }
 
 
   public function isWaiting() {
     switch ($this->getTargetStatus()) {
       case self::STATUS_WAITING:
         return true;
     }
 
     return false;
   }
 
   public function isUnderway() {
     switch ($this->getTargetStatus()) {
       case self::STATUS_PENDING:
       case self::STATUS_BUILDING:
         return true;
     }
 
     return false;
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getBuild()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getBuild()->hasAutomaticCapability(
       $capability,
       $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return pht('Users must be able to see a build to view its build targets.');
   }
 
 }
diff --git a/src/applications/harbormaster/storage/configuration/HarbormasterBuildStep.php b/src/applications/harbormaster/storage/configuration/HarbormasterBuildStep.php
index 557e17ab34..82f61ad9e0 100644
--- a/src/applications/harbormaster/storage/configuration/HarbormasterBuildStep.php
+++ b/src/applications/harbormaster/storage/configuration/HarbormasterBuildStep.php
@@ -1,129 +1,134 @@
 <?php
 
 final class HarbormasterBuildStep extends HarbormasterDAO
   implements
     PhabricatorPolicyInterface,
     PhabricatorCustomFieldInterface {
 
   protected $name;
   protected $description;
   protected $buildPlanPHID;
   protected $className;
   protected $details = array();
   protected $sequence = 0;
 
   private $buildPlan = self::ATTACHABLE;
   private $customFields = self::ATTACHABLE;
   private $implementation;
 
   public static function initializeNewStep(PhabricatorUser $actor) {
     return id(new HarbormasterBuildStep());
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'details' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'className' => 'text255',
         'sequence' => 'uint32',
-        'name' => 'text255',
         'description' => 'text',
+
+        // T6203/NULLABILITY
+        // This should not be nullable. Current `null` values indicate steps
+        // which predated editable names. These should be backfilled with
+        // default names, then the code for handling `null` shoudl be removed.
+        'name' => 'text255?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_plan' => array(
           'columns' => array('buildPlanPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       HarbormasterBuildStepPHIDType::TYPECONST);
   }
 
   public function attachBuildPlan(HarbormasterBuildPlan $plan) {
     $this->buildPlan = $plan;
     return $this;
   }
 
   public function getBuildPlan() {
     return $this->assertAttached($this->buildPlan);
   }
 
   public function getDetail($key, $default = null) {
     return idx($this->details, $key, $default);
   }
 
   public function setDetail($key, $value) {
     $this->details[$key] = $value;
     return $this;
   }
 
   public function getName() {
     if (strlen($this->name)) {
       return $this->name;
     }
 
     return $this->getStepImplementation()->getName();
   }
 
   public function getStepImplementation() {
     if ($this->implementation === null) {
       $obj = HarbormasterBuildStepImplementation::requireImplementation(
         $this->className);
       $obj->loadSettings($this);
       $this->implementation = $obj;
     }
 
     return $this->implementation;
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getBuildPlan()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getBuildPlan()->hasAutomaticCapability($capability, $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return pht('A build step has the same policies as its build plan.');
   }
 
 
 /* -(  PhabricatorCustomFieldInterface  )------------------------------------ */
 
 
   public function getCustomFieldSpecificationForRole($role) {
     return array();
   }
 
   public function getCustomFieldBaseClass() {
     return 'HarbormasterBuildStepCustomField';
   }
 
   public function getCustomFields() {
     return $this->assertAttached($this->customFields);
   }
 
   public function attachCustomFields(PhabricatorCustomFieldAttachment $fields) {
     $this->customFields = $fields;
     return $this;
   }
 
 
 }
diff --git a/src/applications/herald/storage/HeraldRule.php b/src/applications/herald/storage/HeraldRule.php
index 9f921b705d..938edfb707 100644
--- a/src/applications/herald/storage/HeraldRule.php
+++ b/src/applications/herald/storage/HeraldRule.php
@@ -1,292 +1,295 @@
 <?php
 
 final class HeraldRule extends HeraldDAO
   implements
     PhabricatorFlaggableInterface,
     PhabricatorPolicyInterface,
     PhabricatorDestructibleInterface {
 
   const TABLE_RULE_APPLIED = 'herald_ruleapplied';
 
   protected $name;
   protected $authorPHID;
 
   protected $contentType;
   protected $mustMatchAll;
   protected $repetitionPolicy;
   protected $ruleType;
   protected $isDisabled = 0;
   protected $triggerObjectPHID;
 
   protected $configVersion = 37;
 
   // PHIDs for which this rule has been applied
   private $ruleApplied = self::ATTACHABLE;
   private $validAuthor = self::ATTACHABLE;
   private $author = self::ATTACHABLE;
   private $conditions;
   private $actions;
   private $triggerObject = self::ATTACHABLE;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
         'name' => 'text255',
         'contentType' => 'text255',
         'mustMatchAll' => 'bool',
         'configVersion' => 'uint32',
-        'repetitionPolicy' => 'uint32',
         'ruleType' => 'text255',
         'isDisabled' => 'uint32',
         'triggerObjectPHID' => 'phid?',
+
+        // T6203/NULLABILITY
+        // This should not be nullable.
+        'repetitionPolicy' => 'uint32?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID', 'name'),
           'unique' => true,
         ),
         'IDX_RULE_TYPE' => array(
           'columns' => array('ruleType'),
         ),
         'key_trigger' => array(
           'columns' => array('triggerObjectPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(HeraldRulePHIDType::TYPECONST);
   }
 
   public function getRuleApplied($phid) {
     return $this->assertAttachedKey($this->ruleApplied, $phid);
   }
 
   public function setRuleApplied($phid, $applied) {
     if ($this->ruleApplied === self::ATTACHABLE) {
       $this->ruleApplied = array();
     }
     $this->ruleApplied[$phid] = $applied;
     return $this;
   }
 
   public function loadConditions() {
     if (!$this->getID()) {
       return array();
     }
     return id(new HeraldCondition())->loadAllWhere(
       'ruleID = %d',
       $this->getID());
   }
 
   public function attachConditions(array $conditions) {
     assert_instances_of($conditions, 'HeraldCondition');
     $this->conditions = $conditions;
     return $this;
   }
 
   public function getConditions() {
     // TODO: validate conditions have been attached.
     return $this->conditions;
   }
 
   public function loadActions() {
     if (!$this->getID()) {
       return array();
     }
     return id(new HeraldAction())->loadAllWhere(
       'ruleID = %d',
       $this->getID());
   }
 
   public function attachActions(array $actions) {
     // TODO: validate actions have been attached.
     assert_instances_of($actions, 'HeraldAction');
     $this->actions = $actions;
     return $this;
   }
 
   public function getActions() {
     return $this->actions;
   }
 
   public function loadEdits() {
     if (!$this->getID()) {
       return array();
     }
     $edits = id(new HeraldRuleEdit())->loadAllWhere(
       'ruleID = %d ORDER BY dateCreated DESC',
       $this->getID());
 
     return $edits;
   }
 
   public function logEdit($editor_phid, $action) {
     id(new HeraldRuleEdit())
       ->setRuleID($this->getID())
       ->setRuleName($this->getName())
       ->setEditorPHID($editor_phid)
       ->setAction($action)
       ->save();
   }
 
   public function saveConditions(array $conditions) {
     assert_instances_of($conditions, 'HeraldCondition');
     return $this->saveChildren(
       id(new HeraldCondition())->getTableName(),
       $conditions);
   }
 
   public function saveActions(array $actions) {
     assert_instances_of($actions, 'HeraldAction');
     return $this->saveChildren(
       id(new HeraldAction())->getTableName(),
       $actions);
   }
 
   protected function saveChildren($table_name, array $children) {
     assert_instances_of($children, 'HeraldDAO');
 
     if (!$this->getID()) {
       throw new Exception('Save rule before saving children.');
     }
 
     foreach ($children as $child) {
       $child->setRuleID($this->getID());
     }
 
     $this->openTransaction();
       queryfx(
         $this->establishConnection('w'),
         'DELETE FROM %T WHERE ruleID = %d',
         $table_name,
         $this->getID());
       foreach ($children as $child) {
         $child->save();
       }
     $this->saveTransaction();
   }
 
   public function delete() {
     $this->openTransaction();
       queryfx(
         $this->establishConnection('w'),
         'DELETE FROM %T WHERE ruleID = %d',
         id(new HeraldCondition())->getTableName(),
         $this->getID());
       queryfx(
         $this->establishConnection('w'),
         'DELETE FROM %T WHERE ruleID = %d',
         id(new HeraldAction())->getTableName(),
         $this->getID());
       $result = parent::delete();
     $this->saveTransaction();
 
     return $result;
   }
 
   public function hasValidAuthor() {
     return $this->assertAttached($this->validAuthor);
   }
 
   public function attachValidAuthor($valid) {
     $this->validAuthor = $valid;
     return $this;
   }
 
   public function getAuthor() {
     return $this->assertAttached($this->author);
   }
 
   public function attachAuthor(PhabricatorUser $user) {
     $this->author = $user;
     return $this;
   }
 
   public function isGlobalRule() {
     return ($this->getRuleType() === HeraldRuleTypeConfig::RULE_TYPE_GLOBAL);
   }
 
   public function isPersonalRule() {
     return ($this->getRuleType() === HeraldRuleTypeConfig::RULE_TYPE_PERSONAL);
   }
 
   public function isObjectRule() {
     return ($this->getRuleType() == HeraldRuleTypeConfig::RULE_TYPE_OBJECT);
   }
 
   public function attachTriggerObject($trigger_object) {
     $this->triggerObject = $trigger_object;
     return $this;
   }
 
   public function getTriggerObject() {
     return $this->assertAttached($this->triggerObject);
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     if ($this->isGlobalRule()) {
       switch ($capability) {
         case PhabricatorPolicyCapability::CAN_VIEW:
           return PhabricatorPolicies::POLICY_USER;
         case PhabricatorPolicyCapability::CAN_EDIT:
           $app = 'PhabricatorHeraldApplication';
           $herald = PhabricatorApplication::getByClass($app);
           $global = HeraldManageGlobalRulesCapability::CAPABILITY;
           return $herald->getPolicy($global);
       }
     } else if ($this->isObjectRule()) {
       return $this->getTriggerObject()->getPolicy($capability);
     } else {
       return PhabricatorPolicies::POLICY_NOONE;
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     if ($this->isPersonalRule()) {
       return ($viewer->getPHID() == $this->getAuthorPHID());
     } else {
       return false;
     }
   }
 
   public function describeAutomaticCapability($capability) {
     if ($this->isPersonalRule()) {
       return pht("A personal rule's owner can always view and edit it.");
     } else if ($this->isObjectRule()) {
       return pht('Object rules inherit the policies of their objects.');
     }
 
     return null;
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
     $this->delete();
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/maniphest/storage/ManiphestTask.php b/src/applications/maniphest/storage/ManiphestTask.php
index 1174bd68ff..d85c2155f5 100644
--- a/src/applications/maniphest/storage/ManiphestTask.php
+++ b/src/applications/maniphest/storage/ManiphestTask.php
@@ -1,369 +1,374 @@
 <?php
 
 final class ManiphestTask extends ManiphestDAO
   implements
     PhabricatorMarkupInterface,
     PhabricatorPolicyInterface,
     PhabricatorTokenReceiverInterface,
     PhabricatorFlaggableInterface,
     PhabricatorMentionableInterface,
     PhrequentTrackableInterface,
     PhabricatorCustomFieldInterface,
     PhabricatorDestructibleInterface,
     PhabricatorApplicationTransactionInterface,
     PhabricatorProjectInterface {
 
   const MARKUP_FIELD_DESCRIPTION = 'markup:desc';
 
   protected $authorPHID;
   protected $ownerPHID;
   protected $ccPHIDs = array();
 
   protected $status;
   protected $priority;
   protected $subpriority = 0;
 
   protected $title = '';
   protected $originalTitle = '';
   protected $description = '';
   protected $originalEmailSource;
   protected $mailKey;
   protected $viewPolicy = PhabricatorPolicies::POLICY_USER;
   protected $editPolicy = PhabricatorPolicies::POLICY_USER;
 
   protected $attached = array();
   protected $projectPHIDs = array();
   private $subscribersNeedUpdate;
 
   protected $ownerOrdering;
 
   private $groupByProjectPHID = self::ATTACHABLE;
   private $customFields = self::ATTACHABLE;
   private $edgeProjectPHIDs = self::ATTACHABLE;
 
   public static function initializeNewTask(PhabricatorUser $actor) {
     $app = id(new PhabricatorApplicationQuery())
       ->setViewer($actor)
       ->withClasses(array('PhabricatorManiphestApplication'))
       ->executeOne();
 
     $view_policy = $app->getPolicy(ManiphestDefaultViewCapability::CAPABILITY);
     $edit_policy = $app->getPolicy(ManiphestDefaultEditCapability::CAPABILITY);
 
     return id(new ManiphestTask())
       ->setStatus(ManiphestTaskStatus::getDefaultStatus())
       ->setPriority(ManiphestTaskPriority::getDefaultPriority())
       ->setAuthorPHID($actor->getPHID())
       ->setViewPolicy($view_policy)
       ->setEditPolicy($edit_policy)
       ->attachProjectPHIDs(array());
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'ccPHIDs' => self::SERIALIZATION_JSON,
         'attached' => self::SERIALIZATION_JSON,
         'projectPHIDs' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'ownerPHID' => 'phid?',
         'status' => 'text12',
         'priority' => 'uint32',
         'title' => 'text',
         'originalTitle' => 'text',
         'description' => 'text',
         'mailKey' => 'bytes20',
         'ownerOrdering' => 'text64?',
         'originalEmailSource' => 'text255?',
         'subpriority' => 'double',
+
+        // T6203/NULLABILITY
+        // This should not be nullable. It's going away soon anyway.
+        'ccPHIDs' => 'text?',
+
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'priority' => array(
           'columns' => array('priority', 'status'),
         ),
         'status' => array(
           'columns' => array('status'),
         ),
         'ownerPHID' => array(
           'columns' => array('ownerPHID', 'status'),
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID', 'status'),
         ),
         'ownerOrdering' => array(
           'columns' => array('ownerOrdering'),
         ),
         'priority_2' => array(
           'columns' => array('priority', 'subpriority'),
         ),
         'key_dateCreated' => array(
           'columns' => array('dateCreated'),
         ),
         'key_dateModified' => array(
           'columns' => array('dateModified'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function loadDependsOnTaskPHIDs() {
     return PhabricatorEdgeQuery::loadDestinationPHIDs(
       $this->getPHID(),
       PhabricatorEdgeConfig::TYPE_TASK_DEPENDS_ON_TASK);
   }
 
   public function loadDependedOnByTaskPHIDs() {
     return PhabricatorEdgeQuery::loadDestinationPHIDs(
       $this->getPHID(),
       PhabricatorEdgeConfig::TYPE_TASK_DEPENDED_ON_BY_TASK);
   }
 
   public function getAttachedPHIDs($type) {
     return array_keys(idx($this->attached, $type, array()));
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(ManiphestTaskPHIDType::TYPECONST);
   }
 
   public function getCCPHIDs() {
     return array_values(nonempty($this->ccPHIDs, array()));
   }
 
   public function getProjectPHIDs() {
     return $this->assertAttached($this->edgeProjectPHIDs);
   }
 
   public function attachProjectPHIDs(array $phids) {
     $this->edgeProjectPHIDs = $phids;
     return $this;
   }
 
   public function setCCPHIDs(array $phids) {
     $this->ccPHIDs = array_values($phids);
     $this->subscribersNeedUpdate = true;
     return $this;
   }
 
   public function setOwnerPHID($phid) {
     $this->ownerPHID = nonempty($phid, null);
     $this->subscribersNeedUpdate = true;
     return $this;
   }
 
   public function setTitle($title) {
     $this->title = $title;
     if (!$this->getID()) {
       $this->originalTitle = $title;
     }
     return $this;
   }
 
   public function getMonogram() {
     return 'T'.$this->getID();
   }
 
   public function attachGroupByProjectPHID($phid) {
     $this->groupByProjectPHID = $phid;
     return $this;
   }
 
   public function getGroupByProjectPHID() {
     return $this->assertAttached($this->groupByProjectPHID);
   }
 
   public function save() {
     if (!$this->mailKey) {
       $this->mailKey = Filesystem::readRandomCharacters(20);
     }
 
     $result = parent::save();
 
     if ($this->subscribersNeedUpdate) {
       // If we've changed the subscriber PHIDs for this task, update the link
       // table.
       ManiphestTaskSubscriber::updateTaskSubscribers($this);
       $this->subscribersNeedUpdate = false;
     }
 
     return $result;
   }
 
   public function isClosed() {
     return ManiphestTaskStatus::isClosedStatus($this->getStatus());
   }
 
   public function getPrioritySortVector() {
     return array(
       $this->getPriority(),
       -$this->getSubpriority(),
       $this->getID(),
     );
   }
 
 
 /* -(  Markup Interface  )--------------------------------------------------- */
 
 
   /**
    * @task markup
    */
   public function getMarkupFieldKey($field) {
     $hash = PhabricatorHash::digest($this->getMarkupText($field));
     $id = $this->getID();
     return "maniphest:T{$id}:{$field}:{$hash}";
   }
 
 
   /**
    * @task markup
    */
   public function getMarkupText($field) {
     return $this->getDescription();
   }
 
 
   /**
    * @task markup
    */
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::newManiphestMarkupEngine();
   }
 
 
   /**
    * @task markup
    */
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
     return $output;
   }
 
 
   /**
    * @task markup
    */
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getID();
   }
 
 
 /* -(  Policy Interface  )--------------------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getViewPolicy();
       case PhabricatorPolicyCapability::CAN_EDIT:
         return $this->getEditPolicy();
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $user) {
     // The owner of a task can always view and edit it.
     $owner_phid = $this->getOwnerPHID();
     if ($owner_phid) {
       $user_phid = $user->getPHID();
       if ($user_phid == $owner_phid) {
         return true;
       }
     }
 
     return false;
   }
 
   public function describeAutomaticCapability($capability) {
     return pht('The owner of a task can always view and edit it.');
   }
 
 
 /* -(  PhabricatorTokenReceiverInterface  )---------------------------------- */
 
 
   public function getUsersToNotifyOfTokenGiven() {
     // Sort of ambiguous who this was intended for; just let them both know.
     return array_filter(
       array_unique(
         array(
           $this->getAuthorPHID(),
           $this->getOwnerPHID(),
         )));
   }
 
 
 /* -(  PhabricatorCustomFieldInterface  )------------------------------------ */
 
 
   public function getCustomFieldSpecificationForRole($role) {
     return PhabricatorEnv::getEnvConfig('maniphest.fields');
   }
 
   public function getCustomFieldBaseClass() {
     return 'ManiphestCustomField';
   }
 
   public function getCustomFields() {
     return $this->assertAttached($this->customFields);
   }
 
   public function attachCustomFields(PhabricatorCustomFieldAttachment $fields) {
     $this->customFields = $fields;
     return $this;
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
 
       // TODO: Once this implements PhabricatorTransactionInterface, this
       // will be handled automatically and can be removed.
       $xactions = id(new ManiphestTransaction())->loadAllWhere(
         'objectPHID = %s',
         $this->getPHID());
       foreach ($xactions as $xaction) {
         $engine->destroyObject($xaction);
       }
 
       $this->delete();
     $this->saveTransaction();
   }
 
 
 /* -(  PhabricatorApplicationTransactionInterface  )------------------------- */
 
 
   public function getApplicationTransactionEditor() {
     return new ManiphestTransactionEditor();
   }
 
   public function getApplicationTransactionObject() {
     return $this;
   }
 
   public function getApplicationTransactionTemplate() {
     return new ManiphestTransaction();
   }
 
 }
diff --git a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
index d7882231ec..e5cf6f46dd 100644
--- a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
+++ b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
@@ -1,955 +1,958 @@
 <?php
 
 /**
  * @task recipients   Managing Recipients
  */
 final class PhabricatorMetaMTAMail extends PhabricatorMetaMTADAO {
 
   const STATUS_QUEUE = 'queued';
   const STATUS_SENT  = 'sent';
   const STATUS_FAIL  = 'fail';
   const STATUS_VOID  = 'void';
 
   const RETRY_DELAY   = 5;
 
   protected $parameters;
   protected $status;
   protected $message;
   protected $relatedPHID;
 
   private $recipientExpansionMap;
 
   public function __construct() {
 
     $this->status     = self::STATUS_QUEUE;
     $this->parameters = array();
 
     parent::__construct();
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_SERIALIZATION => array(
         'parameters'  => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'status' => 'text255',
-        'message' => 'text',
         'relatedPHID' => 'phid?',
+
+        // T6203/NULLABILITY
+        // This should just be empty if there's no body.
+        'message' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'status' => array(
           'columns' => array('status'),
         ),
         'relatedPHID' => array(
           'columns' => array('relatedPHID'),
         ),
         'key_created' => array(
           'columns' => array('dateCreated'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   protected function setParam($param, $value) {
     $this->parameters[$param] = $value;
     return $this;
   }
 
   protected function getParam($param, $default = null) {
     return idx($this->parameters, $param, $default);
   }
 
   /**
    * Set tags (@{class:MetaMTANotificationType} constants) which identify the
    * content of this mail in a general way. These tags are used to allow users
    * to opt out of receiving certain types of mail, like updates when a task's
    * projects change.
    *
    * @param list<const> List of @{class:MetaMTANotificationType} constants.
    * @return this
    */
   public function setMailTags(array $tags) {
     $this->setParam('mailtags', array_unique($tags));
     return $this;
   }
 
   public function getMailTags() {
     return $this->getParam('mailtags', array());
   }
 
   /**
    * In Gmail, conversations will be broken if you reply to a thread and the
    * server sends back a response without referencing your Message-ID, even if
    * it references a Message-ID earlier in the thread. To avoid this, use the
    * parent email's message ID explicitly if it's available. This overwrites the
    * "In-Reply-To" and "References" headers we would otherwise generate. This
    * needs to be set whenever an action is triggered by an email message. See
    * T251 for more details.
    *
    * @param   string The "Message-ID" of the email which precedes this one.
    * @return  this
    */
   public function setParentMessageID($id) {
     $this->setParam('parent-message-id', $id);
     return $this;
   }
 
   public function getParentMessageID() {
     return $this->getParam('parent-message-id');
   }
 
   public function getSubject() {
     return $this->getParam('subject');
   }
 
   public function addTos(array $phids) {
     $phids = array_unique($phids);
     $this->setParam('to', $phids);
     return $this;
   }
 
   public function addRawTos(array $raw_email) {
 
     // Strip addresses down to bare emails, since the MailAdapter API currently
     // requires we pass it just the address (like `alincoln@logcabin.org`), not
     // a full string like `"Abraham Lincoln" <alincoln@logcabin.org>`.
     foreach ($raw_email as $key => $email) {
       $object = new PhutilEmailAddress($email);
       $raw_email[$key] = $object->getAddress();
     }
 
     $this->setParam('raw-to', $raw_email);
     return $this;
   }
 
   public function addCCs(array $phids) {
     $phids = array_unique($phids);
     $this->setParam('cc', $phids);
     return $this;
   }
 
   public function setExcludeMailRecipientPHIDs(array $exclude) {
     $this->setParam('exclude', $exclude);
     return $this;
   }
 
   private function getExcludeMailRecipientPHIDs() {
     return $this->getParam('exclude', array());
   }
 
   public function getTranslation(array $objects) {
     $default_translation = PhabricatorEnv::getEnvConfig('translation.provider');
     $return = null;
     $recipients = array_merge(
       idx($this->parameters, 'to', array()),
       idx($this->parameters, 'cc', array()));
     foreach (array_select_keys($objects, $recipients) as $object) {
       $translation = null;
       if ($object instanceof PhabricatorUser) {
         $translation = $object->getTranslation();
       }
       if (!$translation) {
         $translation = $default_translation;
       }
       if ($return && $translation != $return) {
         return $default_translation;
       }
       $return = $translation;
     }
 
     if (!$return) {
       $return = $default_translation;
     }
 
     return $return;
   }
 
   public function addPHIDHeaders($name, array $phids) {
     foreach ($phids as $phid) {
       $this->addHeader($name, '<'.$phid.'>');
     }
     return $this;
   }
 
   public function addHeader($name, $value) {
     $this->parameters['headers'][] = array($name, $value);
     return $this;
   }
 
   public function addAttachment(PhabricatorMetaMTAAttachment $attachment) {
     $this->parameters['attachments'][] = $attachment->toDictionary();
     return $this;
   }
 
   public function getAttachments() {
     $dicts = $this->getParam('attachments');
 
     $result = array();
     foreach ($dicts as $dict) {
       $result[] = PhabricatorMetaMTAAttachment::newFromDictionary($dict);
     }
     return $result;
   }
 
   public function setAttachments(array $attachments) {
     assert_instances_of($attachments, 'PhabricatorMetaMTAAttachment');
     $this->setParam('attachments', mpull($attachments, 'toDictionary'));
     return $this;
   }
 
   public function setFrom($from) {
     $this->setParam('from', $from);
     return $this;
   }
 
   public function setReplyTo($reply_to) {
     $this->setParam('reply-to', $reply_to);
     return $this;
   }
 
   public function setSubject($subject) {
     $this->setParam('subject', $subject);
     return $this;
   }
 
   public function setSubjectPrefix($prefix) {
     $this->setParam('subject-prefix', $prefix);
     return $this;
   }
 
   public function setVarySubjectPrefix($prefix) {
     $this->setParam('vary-subject-prefix', $prefix);
     return $this;
   }
 
   public function setBody($body) {
     $this->setParam('body', $body);
     return $this;
   }
 
   public function setHTMLBody($html) {
     $this->setParam('html-body', $html);
     return $this;
   }
 
   public function getBody() {
     return $this->getParam('body');
   }
 
   public function getHTMLBody() {
     return $this->getParam('html-body');
   }
 
   public function setIsErrorEmail($is_error) {
     $this->setParam('is-error', $is_error);
     return $this;
   }
 
   public function getIsErrorEmail() {
     return $this->getParam('is-error', false);
   }
 
   public function getToPHIDs() {
     return $this->getParam('to', array());
   }
 
   public function getRawToAddresses() {
     return $this->getParam('raw-to', array());
   }
 
   public function getCcPHIDs() {
     return $this->getParam('cc', array());
   }
 
   /**
    * Force delivery of a message, even if recipients have preferences which
    * would otherwise drop the message.
    *
    * This is primarily intended to let users who don't want any email still
    * receive things like password resets.
    *
    * @param bool  True to force delivery despite user preferences.
    * @return this
    */
   public function setForceDelivery($force) {
     $this->setParam('force', $force);
     return $this;
   }
 
   public function getForceDelivery() {
     return $this->getParam('force', false);
   }
 
   /**
    * Flag that this is an auto-generated bulk message and should have bulk
    * headers added to it if appropriate. Broadly, this means some flavor of
    * "Precedence: bulk" or similar, but is implementation and configuration
    * dependent.
    *
    * @param bool  True if the mail is automated bulk mail.
    * @return this
    */
   public function setIsBulk($is_bulk) {
     $this->setParam('is-bulk', $is_bulk);
     return $this;
   }
 
   /**
    * Use this method to set an ID used for message threading. MetaMTA will
    * set appropriate headers (Message-ID, In-Reply-To, References and
    * Thread-Index) based on the capabilities of the underlying mailer.
    *
    * @param string  Unique identifier, appropriate for use in a Message-ID,
    *                In-Reply-To or References headers.
    * @param bool    If true, indicates this is the first message in the thread.
    * @return this
    */
   public function setThreadID($thread_id, $is_first_message = false) {
     $this->setParam('thread-id', $thread_id);
     $this->setParam('is-first-message', $is_first_message);
     return $this;
   }
 
   /**
    * Save a newly created mail to the database. The mail will eventually be
    * delivered by the MetaMTA daemon.
    *
    * @return this
    */
   public function saveAndSend() {
     return $this->save();
   }
 
   public function save() {
     if ($this->getID()) {
       return parent::save();
     }
 
     // NOTE: When mail is sent from CLI scripts that run tasks in-process, we
     // may re-enter this method from within scheduleTask(). The implementation
     // is intended to avoid anything awkward if we end up reentering this
     // method.
 
     $this->openTransaction();
       // Save to generate a task ID.
       $result = parent::save();
 
       // Queue a task to send this mail.
       $mailer_task = PhabricatorWorker::scheduleTask(
         'PhabricatorMetaMTAWorker',
         $this->getID(),
         PhabricatorWorker::PRIORITY_ALERTS);
 
     $this->saveTransaction();
 
     return $result;
   }
 
   public function buildDefaultMailer() {
     return PhabricatorEnv::newObjectFromConfig('metamta.mail-adapter');
   }
 
 
   /**
    * Attempt to deliver an email immediately, in this process.
    *
    * @param bool  Try to deliver this email even if it has already been
    *              delivered or is in backoff after a failed delivery attempt.
    * @param PhabricatorMailImplementationAdapter Use a specific mail adapter,
    *              instead of the default.
    *
    * @return void
    */
   public function sendNow(
     $force_send = false,
     PhabricatorMailImplementationAdapter $mailer = null) {
 
     if ($mailer === null) {
       $mailer = $this->buildDefaultMailer();
     }
 
     if (!$force_send) {
       if ($this->getStatus() != self::STATUS_QUEUE) {
         throw new Exception('Trying to send an already-sent mail!');
       }
     }
 
     try {
       $params = $this->parameters;
 
       $actors = $this->loadAllActors();
       $deliverable_actors = $this->filterDeliverableActors($actors);
 
       $default_from = PhabricatorEnv::getEnvConfig('metamta.default-address');
       if (empty($params['from'])) {
         $mailer->setFrom($default_from);
       }
 
       $is_first = idx($params, 'is-first-message');
       unset($params['is-first-message']);
 
       $is_threaded = (bool)idx($params, 'thread-id');
 
       $reply_to_name = idx($params, 'reply-to-name', '');
       unset($params['reply-to-name']);
 
       $add_cc = array();
       $add_to = array();
 
       // Only try to use preferences if everything is multiplexed, so we
       // get consistent behavior.
       $use_prefs = self::shouldMultiplexAllMail();
 
       $prefs = null;
       if ($use_prefs) {
 
         // If multiplexing is enabled, some recipients will be in "Cc"
         // rather than "To". We'll move them to "To" later (or supply a
         // dummy "To") but need to look for the recipient in either the
         // "To" or "Cc" fields here.
         $target_phid = head(idx($params, 'to', array()));
         if (!$target_phid) {
           $target_phid = head(idx($params, 'cc', array()));
         }
 
         if ($target_phid) {
           $user = id(new PhabricatorUser())->loadOneWhere(
             'phid = %s',
             $target_phid);
           if ($user) {
             $prefs = $user->loadPreferences();
           }
         }
       }
 
       foreach ($params as $key => $value) {
         switch ($key) {
           case 'from':
             $from = $value;
             $actor_email = null;
             $actor_name = null;
             $actor = idx($actors, $from);
             if ($actor) {
               $actor_email = $actor->getEmailAddress();
               $actor_name = $actor->getName();
             }
             $can_send_as_user = $actor_email &&
               PhabricatorEnv::getEnvConfig('metamta.can-send-as-user');
 
             if ($can_send_as_user) {
               $mailer->setFrom($actor_email, $actor_name);
             } else {
               $from_email = coalesce($actor_email, $default_from);
               $from_name = coalesce($actor_name, pht('Phabricator'));
 
               if (empty($params['reply-to'])) {
                 $params['reply-to'] = $from_email;
                 $params['reply-to-name'] = $from_name;
               }
 
               $mailer->setFrom($default_from, $from_name);
             }
             break;
           case 'reply-to':
             $mailer->addReplyTo($value, $reply_to_name);
             break;
           case 'to':
             $to_phids = $this->expandRecipients($value);
             $to_actors = array_select_keys($deliverable_actors, $to_phids);
             $add_to = array_merge(
               $add_to,
               mpull($to_actors, 'getEmailAddress'));
             break;
           case 'raw-to':
             $add_to = array_merge($add_to, $value);
             break;
           case 'cc':
             $cc_phids = $this->expandRecipients($value);
             $cc_actors = array_select_keys($deliverable_actors, $cc_phids);
             $add_cc = array_merge(
               $add_cc,
               mpull($cc_actors, 'getEmailAddress'));
             break;
           case 'headers':
             foreach ($value as $pair) {
               list($header_key, $header_value) = $pair;
 
               // NOTE: If we have \n in a header, SES rejects the email.
               $header_value = str_replace("\n", ' ', $header_value);
 
               $mailer->addHeader($header_key, $header_value);
             }
             break;
           case 'attachments':
             $value = $this->getAttachments();
             foreach ($value as $attachment) {
               $mailer->addAttachment(
                 $attachment->getData(),
                 $attachment->getFilename(),
                 $attachment->getMimeType());
             }
             break;
           case 'subject':
             $subject = array();
 
             if ($is_threaded) {
               $add_re = PhabricatorEnv::getEnvConfig('metamta.re-prefix');
 
               if ($prefs) {
                 $add_re = $prefs->getPreference(
                   PhabricatorUserPreferences::PREFERENCE_RE_PREFIX,
                   $add_re);
               }
 
               if ($add_re) {
                 $subject[] = 'Re:';
               }
             }
 
             $subject[] = trim(idx($params, 'subject-prefix'));
 
             $vary_prefix = idx($params, 'vary-subject-prefix');
             if ($vary_prefix != '') {
               $use_subject = PhabricatorEnv::getEnvConfig(
                 'metamta.vary-subjects');
 
               if ($prefs) {
                 $use_subject = $prefs->getPreference(
                   PhabricatorUserPreferences::PREFERENCE_VARY_SUBJECT,
                   $use_subject);
               }
 
               if ($use_subject) {
                 $subject[] = $vary_prefix;
               }
             }
 
             $subject[] = $value;
 
             $mailer->setSubject(implode(' ', array_filter($subject)));
             break;
           case 'is-bulk':
             if ($value) {
               if (PhabricatorEnv::getEnvConfig('metamta.precedence-bulk')) {
                 $mailer->addHeader('Precedence', 'bulk');
               }
             }
             break;
           case 'thread-id':
 
             // NOTE: Gmail freaks out about In-Reply-To and References which
             // aren't in the form "<string@domain.tld>"; this is also required
             // by RFC 2822, although some clients are more liberal in what they
             // accept.
             $domain = PhabricatorEnv::getEnvConfig('metamta.domain');
             $value = '<'.$value.'@'.$domain.'>';
 
             if ($is_first && $mailer->supportsMessageIDHeader()) {
               $mailer->addHeader('Message-ID',  $value);
             } else {
               $in_reply_to = $value;
               $references = array($value);
               $parent_id = $this->getParentMessageID();
               if ($parent_id) {
                 $in_reply_to = $parent_id;
                 // By RFC 2822, the most immediate parent should appear last
                 // in the "References" header, so this order is intentional.
                 $references[] = $parent_id;
               }
               $references = implode(' ', $references);
               $mailer->addHeader('In-Reply-To', $in_reply_to);
               $mailer->addHeader('References',  $references);
             }
             $thread_index = $this->generateThreadIndex($value, $is_first);
             $mailer->addHeader('Thread-Index', $thread_index);
             break;
           case 'mailtags':
             // Handled below.
             break;
           case 'subject-prefix':
           case 'vary-subject-prefix':
             // Handled above.
             break;
           default:
             // Just discard.
         }
       }
 
       $body = idx($params, 'body', '');
       $max = PhabricatorEnv::getEnvConfig('metamta.email-body-limit');
       if (strlen($body) > $max) {
         $body = id(new PhutilUTF8StringTruncator())
           ->setMaximumBytes($max)
           ->truncateString($body);
         $body .= "\n";
         $body .= pht('(This email was truncated at %d bytes.)', $max);
       }
       $mailer->setBody($body);
 
       $html_emails = false;
       if ($use_prefs && $prefs) {
         $html_emails = $prefs->getPreference(
           PhabricatorUserPreferences::PREFERENCE_HTML_EMAILS,
           $html_emails);
       }
 
       if ($html_emails && isset($params['html-body'])) {
         $mailer->setHTMLBody($params['html-body']);
       }
 
       if (!$add_to && !$add_cc) {
         $this->setStatus(self::STATUS_VOID);
         $this->setMessage(
           'Message has no valid recipients: all To/Cc are disabled, invalid, '.
           'or configured not to receive this mail.');
         return $this->save();
       }
 
       if ($this->getIsErrorEmail()) {
         $all_recipients = array_merge($add_to, $add_cc);
         if ($this->shouldRateLimitMail($all_recipients)) {
           $this->setStatus(self::STATUS_VOID);
           $this->setMessage(
             pht(
               'This is an error email, but one or more recipients have '.
               'exceeded the error email rate limit. Declining to deliver '.
               'message.'));
           return $this->save();
         }
       }
 
       $mailer->addHeader('X-Phabricator-Sent-This-Message', 'Yes');
       $mailer->addHeader('X-Mail-Transport-Agent', 'MetaMTA');
 
       // Some clients respect this to suppress OOF and other auto-responses.
       $mailer->addHeader('X-Auto-Response-Suppress', 'All');
 
       // If the message has mailtags, filter out any recipients who don't want
       // to receive this type of mail.
       $mailtags = $this->getParam('mailtags');
       if ($mailtags) {
         $tag_header = array();
         foreach ($mailtags as $mailtag) {
           $tag_header[] = '<'.$mailtag.'>';
         }
         $tag_header = implode(', ', $tag_header);
         $mailer->addHeader('X-Phabricator-Mail-Tags', $tag_header);
       }
 
       // Some mailers require a valid "To:" in order to deliver mail. If we
       // don't have any "To:", try to fill it in with a placeholder "To:".
       // If that also fails, move the "Cc:" line to "To:".
       if (!$add_to) {
         $placeholder_key = 'metamta.placeholder-to-recipient';
         $placeholder = PhabricatorEnv::getEnvConfig($placeholder_key);
         if ($placeholder !== null) {
           $add_to = array($placeholder);
         } else {
           $add_to = $add_cc;
           $add_cc = array();
         }
       }
 
       $add_to = array_unique($add_to);
       $add_cc = array_diff(array_unique($add_cc), $add_to);
 
       $mailer->addTos($add_to);
       if ($add_cc) {
         $mailer->addCCs($add_cc);
       }
     } catch (Exception $ex) {
       $this
         ->setStatus(self::STATUS_FAIL)
         ->setMessage($ex->getMessage())
         ->save();
 
       throw $ex;
     }
 
     try {
       $ok = $mailer->send();
       if (!$ok) {
         // TODO: At some point, we should clean this up and make all mailers
         // throw.
         throw new Exception(
           pht('Mail adapter encountered an unexpected, unspecified failure.'));
       }
 
       $this->setStatus(self::STATUS_SENT);
       $this->save();
 
       return $this;
     } catch (PhabricatorMetaMTAPermanentFailureException $ex) {
       $this
         ->setStatus(self::STATUS_FAIL)
         ->setMessage($ex->getMessage())
         ->save();
 
       throw $ex;
     } catch (Exception $ex) {
       $this
         ->setMessage($ex->getMessage()."\n".$ex->getTraceAsString())
         ->save();
 
       throw $ex;
     }
   }
 
   public static function getReadableStatus($status_code) {
     static $readable = array(
       self::STATUS_QUEUE => 'Queued for Delivery',
       self::STATUS_FAIL  => 'Delivery Failed',
       self::STATUS_SENT  => 'Sent',
       self::STATUS_VOID  => 'Void',
     );
     $status_code = coalesce($status_code, '?');
     return idx($readable, $status_code, $status_code);
   }
 
   private function generateThreadIndex($seed, $is_first_mail) {
     // When threading, Outlook ignores the 'References' and 'In-Reply-To'
     // headers that most clients use. Instead, it uses a custom 'Thread-Index'
     // header. The format of this header is something like this (from
     // camel-exchange-folder.c in Evolution Exchange):
 
     /* A new post to a folder gets a 27-byte-long thread index. (The value
      * is apparently unique but meaningless.) Each reply to a post gets a
      * 32-byte-long thread index whose first 27 bytes are the same as the
      * parent's thread index. Each reply to any of those gets a
      * 37-byte-long thread index, etc. The Thread-Index header contains a
      * base64 representation of this value.
      */
 
     // The specific implementation uses a 27-byte header for the first email
     // a recipient receives, and a random 5-byte suffix (32 bytes total)
     // thereafter. This means that all the replies are (incorrectly) siblings,
     // but it would be very difficult to keep track of the entire tree and this
     // gets us reasonable client behavior.
 
     $base = substr(md5($seed), 0, 27);
     if (!$is_first_mail) {
       // Not totally sure, but it seems like outlook orders replies by
       // thread-index rather than timestamp, so to get these to show up in the
       // right order we use the time as the last 4 bytes.
       $base .= ' '.pack('N', time());
     }
 
     return base64_encode($base);
   }
 
   public static function shouldMultiplexAllMail() {
     return PhabricatorEnv::getEnvConfig('metamta.one-mail-per-recipient');
   }
 
 
 /* -(  Managing Recipients  )------------------------------------------------ */
 
 
   /**
    * Get all of the recipients for this mail, after preference filters are
    * applied. This list has all objects to whom delivery will be attempted.
    *
    * @return  list<phid>  A list of all recipients to whom delivery will be
    *                      attempted.
    * @task recipients
    */
   public function buildRecipientList() {
     $actors = $this->loadActors(
       array_merge(
         $this->getToPHIDs(),
         $this->getCcPHIDs()));
     $actors = $this->filterDeliverableActors($actors);
     return mpull($actors, 'getPHID');
   }
 
   public function loadAllActors() {
     $actor_phids = array_merge(
       array($this->getParam('from')),
       $this->getToPHIDs(),
       $this->getCcPHIDs());
 
     $this->loadRecipientExpansions($actor_phids);
     $actor_phids = $this->expandRecipients($actor_phids);
 
     return $this->loadActors($actor_phids);
   }
 
   private function loadRecipientExpansions(array $phids) {
     $expansions = id(new PhabricatorMetaMTAMemberQuery())
       ->setViewer(PhabricatorUser::getOmnipotentUser())
       ->withPHIDs($phids)
       ->execute();
 
     $this->recipientExpansionMap = $expansions;
 
     return $this;
   }
 
   /**
    * Expand a list of recipient PHIDs (possibly including aggregate recipients
    * like projects) into a deaggregated list of individual recipient PHIDs.
    * For example, this will expand project PHIDs into a list of the project's
    * members.
    *
    * @param list<phid>  List of recipient PHIDs, possibly including aggregate
    *                    recipients.
    * @return list<phid> Deaggregated list of mailable recipients.
    */
   private function expandRecipients(array $phids) {
     if ($this->recipientExpansionMap === null) {
       throw new Exception(
         pht(
           'Call loadRecipientExpansions() before expandRecipients()!'));
     }
 
     $results = array();
     foreach ($phids as $phid) {
       if (!isset($this->recipientExpansionMap[$phid])) {
         $results[$phid] = $phid;
       } else {
         foreach ($this->recipientExpansionMap[$phid] as $recipient_phid) {
           $results[$recipient_phid] = $recipient_phid;
         }
       }
     }
 
     return array_keys($results);
   }
 
   private function filterDeliverableActors(array $actors) {
     assert_instances_of($actors, 'PhabricatorMetaMTAActor');
     $deliverable_actors = array();
     foreach ($actors as $phid => $actor) {
       if ($actor->isDeliverable()) {
         $deliverable_actors[$phid] = $actor;
       }
     }
     return $deliverable_actors;
   }
 
   private function loadActors(array $actor_phids) {
     $actor_phids = array_filter($actor_phids);
     $viewer = PhabricatorUser::getOmnipotentUser();
 
     $actors = id(new PhabricatorMetaMTAActorQuery())
       ->setViewer($viewer)
       ->withPHIDs($actor_phids)
       ->execute();
 
     if (!$actors) {
       return array();
     }
 
     if ($this->getForceDelivery()) {
       // If we're forcing delivery, skip all the opt-out checks.
       return $actors;
     }
 
     // Exclude explicit recipients.
     foreach ($this->getExcludeMailRecipientPHIDs() as $phid) {
       $actor = idx($actors, $phid);
       if (!$actor) {
         continue;
       }
       $actor->setUndeliverable(
         pht(
           'This message is a response to another email message, and this '.
           'recipient received the original email message, so we are not '.
           'sending them this substantially similar message (for example, '.
           'the sender used "Reply All" instead of "Reply" in response to '.
           'mail from Phabricator).'));
     }
 
     // Exclude the actor if their preferences are set.
     $from_phid = $this->getParam('from');
     $from_actor = idx($actors, $from_phid);
     if ($from_actor) {
       $from_user = id(new PhabricatorPeopleQuery())
         ->setViewer($viewer)
         ->withPHIDs(array($from_phid))
         ->execute();
       $from_user = head($from_user);
       if ($from_user) {
         $pref_key = PhabricatorUserPreferences::PREFERENCE_NO_SELF_MAIL;
         $exclude_self = $from_user
           ->loadPreferences()
           ->getPreference($pref_key);
         if ($exclude_self) {
           $from_actor->setUndeliverable(
             pht(
               'This recipient is the user whose actions caused delivery of '.
               'this message, but they have set preferences so they do not '.
               'receive mail about their own actions (Settings > Email '.
               'Preferences > Self Actions).'));
         }
       }
     }
 
     $all_prefs = id(new PhabricatorUserPreferences())->loadAllWhere(
       'userPHID in (%Ls)',
       $actor_phids);
     $all_prefs = mpull($all_prefs, null, 'getUserPHID');
 
     // Exclude recipients who don't want any mail.
     foreach ($all_prefs as $phid => $prefs) {
       $exclude = $prefs->getPreference(
         PhabricatorUserPreferences::PREFERENCE_NO_MAIL,
         false);
       if ($exclude) {
         $actors[$phid]->setUndeliverable(
           pht(
             'This recipient has disabled all email notifications '.
             '(Settings > Email Preferences > Email Notifications).'));
       }
     }
 
     $value_email = PhabricatorUserPreferences::MAILTAG_PREFERENCE_EMAIL;
 
     // Exclude all recipients who have set preferences to not receive this type
     // of email (for example, a user who says they don't want emails about task
     // CC changes).
     $tags = $this->getParam('mailtags');
     if ($tags) {
       foreach ($all_prefs as $phid => $prefs) {
         $user_mailtags = $prefs->getPreference(
           PhabricatorUserPreferences::PREFERENCE_MAILTAGS,
           array());
 
         // The user must have elected to receive mail for at least one
         // of the mailtags.
         $send = false;
         foreach ($tags as $tag) {
           if (((int)idx($user_mailtags, $tag, $value_email)) == $value_email) {
             $send = true;
             break;
           }
         }
 
         if (!$send) {
           $actors[$phid]->setUndeliverable(
             pht(
               'This mail has tags which control which users receive it, and '.
               'this recipient has not elected to receive mail with any of '.
               'the tags on this message (Settings > Email Preferences).'));
         }
       }
     }
 
     return $actors;
   }
 
   private function shouldRateLimitMail(array $all_recipients) {
     try {
       PhabricatorSystemActionEngine::willTakeAction(
         $all_recipients,
         new PhabricatorMetaMTAErrorMailAction(),
         1);
       return false;
     } catch (PhabricatorSystemActionRateLimitException $ex) {
       return true;
     }
   }
 
 
 }
diff --git a/src/applications/paste/storage/PhabricatorPaste.php b/src/applications/paste/storage/PhabricatorPaste.php
index 9191f316a2..02f37853af 100644
--- a/src/applications/paste/storage/PhabricatorPaste.php
+++ b/src/applications/paste/storage/PhabricatorPaste.php
@@ -1,193 +1,197 @@
 <?php
 
 final class PhabricatorPaste extends PhabricatorPasteDAO
   implements
     PhabricatorSubscribableInterface,
     PhabricatorTokenReceiverInterface,
     PhabricatorFlaggableInterface,
     PhabricatorMentionableInterface,
     PhabricatorPolicyInterface,
     PhabricatorProjectInterface,
     PhabricatorDestructibleInterface,
     PhabricatorApplicationTransactionInterface {
 
   protected $title;
   protected $authorPHID;
   protected $filePHID;
   protected $language;
   protected $parentPHID;
   protected $viewPolicy;
   protected $mailKey;
 
   private $content = self::ATTACHABLE;
   private $rawContent = self::ATTACHABLE;
 
   public static function initializeNewPaste(PhabricatorUser $actor) {
     $app = id(new PhabricatorApplicationQuery())
       ->setViewer($actor)
       ->withClasses(array('PhabricatorPasteApplication'))
       ->executeOne();
 
     $view_policy = $app->getPolicy(PasteDefaultViewCapability::CAPABILITY);
 
     return id(new PhabricatorPaste())
       ->setTitle('')
       ->setAuthorPHID($actor->getPHID())
       ->setViewPolicy($view_policy);
   }
 
   public function getURI() {
     return '/P'.$this->getID();
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
         'title' => 'text255',
         'language' => 'text64',
         'mailKey' => 'bytes20',
         'parentPHID' => 'phid?',
+
+        // T6203/NULLABILITY
+        // Pastes should always have a view policy.
+        'viewPolicy' => 'policy?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'parentPHID' => array(
           'columns' => array('parentPHID'),
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID'),
         ),
         'key_dateCreated' => array(
           'columns' => array('dateCreated'),
         ),
         'key_language' => array(
           'columns' => array('language'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       PhabricatorPastePastePHIDType::TYPECONST);
   }
 
   public function save() {
     if (!$this->getMailKey()) {
       $this->setMailKey(Filesystem::readRandomCharacters(20));
     }
     return parent::save();
   }
 
   public function getFullName() {
     $title = $this->getTitle();
     if (!$title) {
       $title = pht('(An Untitled Masterwork)');
     }
     return 'P'.$this->getID().' '.$title;
   }
 
   public function getContent() {
     return $this->assertAttached($this->content);
   }
 
   public function attachContent($content) {
     $this->content = $content;
     return $this;
   }
 
   public function getRawContent() {
     return $this->assertAttached($this->rawContent);
   }
 
   public function attachRawContent($raw_content) {
     $this->rawContent = $raw_content;
     return $this;
   }
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
 
   public function isAutomaticallySubscribed($phid) {
     return ($this->authorPHID == $phid);
   }
 
   public function shouldShowSubscribersProperty() {
     return true;
   }
 
   public function shouldAllowSubscription($phid) {
     return true;
   }
 
 
 /* -(  PhabricatorTokenReceiverInterface  )---------------------------------- */
 
   public function getUsersToNotifyOfTokenGiven() {
     return array(
       $this->getAuthorPHID(),
     );
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     if ($capability == PhabricatorPolicyCapability::CAN_VIEW) {
       return $this->viewPolicy;
     }
     return PhabricatorPolicies::POLICY_NOONE;
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $user) {
     return ($user->getPHID() == $this->getAuthorPHID());
   }
 
   public function describeAutomaticCapability($capability) {
     return pht('The author of a paste can always view and edit it.');
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     if ($this->filePHID) {
       $file = id(new PhabricatorFileQuery())
         ->setViewer(PhabricatorUser::getOmnipotentUser())
         ->withPHIDs(array($this->filePHID))
         ->executeOne();
       if ($file) {
         $engine->destroyObject($file);
       }
     }
 
     $this->delete();
   }
 
 
 /* -(  PhabricatorApplicationTransactionInterface  )------------------------- */
 
 
   public function getApplicationTransactionEditor() {
     return new PhabricatorPasteEditor();
   }
 
   public function getApplicationTransactionObject() {
     return $this;
   }
 
   public function getApplicationTransactionTemplate() {
     return new PhabricatorPasteTransaction();
   }
 
 }
diff --git a/src/applications/phame/storage/PhameBlog.php b/src/applications/phame/storage/PhameBlog.php
index beccfdc329..d094359449 100644
--- a/src/applications/phame/storage/PhameBlog.php
+++ b/src/applications/phame/storage/PhameBlog.php
@@ -1,298 +1,303 @@
 <?php
 
 final class PhameBlog extends PhameDAO
   implements PhabricatorPolicyInterface, PhabricatorMarkupInterface {
 
   const MARKUP_FIELD_DESCRIPTION = 'markup:description';
 
   const SKIN_DEFAULT = 'oblivious';
 
   protected $name;
   protected $description;
   protected $domain;
   protected $configData;
   protected $creatorPHID;
   protected $viewPolicy;
   protected $editPolicy;
   protected $joinPolicy;
 
   private $bloggerPHIDs = self::ATTACHABLE;
   private $bloggers = self::ATTACHABLE;
 
   static private $requestBlog;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID   => true,
       self::CONFIG_SERIALIZATION => array(
         'configData' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'name' => 'text64',
         'description' => 'text',
         'domain' => 'text255?',
-        'joinPolicy' => 'policy',
+
+        // T6203/NULLABILITY
+        // These policies should always be non-null.
+        'joinPolicy' => 'policy?',
+        'editPolicy' => 'policy?',
+        'viewPolicy' => 'policy?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'domain' => array(
           'columns' => array('domain'),
           'unique' => true,
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       PhabricatorPhameBlogPHIDType::TYPECONST);
   }
 
   public function getSkinRenderer(AphrontRequest $request) {
     $spec = PhameSkinSpecification::loadOneSkinSpecification(
       $this->getSkin());
 
     if (!$spec) {
       $spec = PhameSkinSpecification::loadOneSkinSpecification(
         self::SKIN_DEFAULT);
     }
 
     if (!$spec) {
       throw new Exception(
         'This blog has an invalid skin, and the default skin failed to '.
         'load.');
     }
 
     $skin = newv($spec->getSkinClass(), array($request));
     $skin->setSpecification($spec);
 
     return $skin;
   }
 
   /**
    * Makes sure a given custom blog uri is properly configured in DNS
    * to point at this Phabricator instance. If there is an error in
    * the configuration, return a string describing the error and how
    * to fix it. If there is no error, return an empty string.
    *
    * @return string
    */
   public function validateCustomDomain($custom_domain) {
     $example_domain = 'blog.example.com';
     $label = pht('Invalid');
 
     // note this "uri" should be pretty busted given the desired input
     // so just use it to test if there's a protocol specified
     $uri = new PhutilURI($custom_domain);
     if ($uri->getProtocol()) {
       return array($label,
         pht(
           'The custom domain should not include a protocol. Just provide '.
           'the bare domain name (for example, "%s").',
           $example_domain));
     }
 
     if ($uri->getPort()) {
       return array($label,
         pht(
           'The custom domain should not include a port number. Just provide '.
           'the bare domain name (for example, "%s").',
           $example_domain));
     }
 
     if (strpos($custom_domain, '/') !== false) {
       return array($label,
         pht(
           'The custom domain should not specify a path (hosting a Phame '.
           'blog at a path is currently not supported). Instead, just provide '.
           'the bare domain name (for example, "%s").',
           $example_domain));
     }
 
     if (strpos($custom_domain, '.') === false) {
       return array($label,
         pht(
           'The custom domain should contain at least one dot (.) because '.
           'some browsers fail to set cookies on domains without a dot. '.
           'Instead, use a normal looking domain name like "%s".',
           $example_domain));
     }
 
     if (!PhabricatorEnv::getEnvConfig('policy.allow-public')) {
       $href = PhabricatorEnv::getProductionURI(
         '/config/edit/policy.allow-public/');
       return array(pht('Fix Configuration'),
         pht(
           'For custom domains to work, this Phabricator instance must be '.
           'configured to allow the public access policy. Configure this '.
           'setting %s, or ask an administrator to configure this setting. '.
           'The domain can be specified later once this setting has been '.
           'changed.',
           phutil_tag(
             'a',
             array('href' => $href),
             pht('here'))));
     }
 
     return null;
   }
 
   public function getBloggerPHIDs() {
     return $this->assertAttached($this->bloggerPHIDs);
   }
 
   public function attachBloggers(array $bloggers) {
     assert_instances_of($bloggers, 'PhabricatorObjectHandle');
 
     $this->bloggers = $bloggers;
 
     return $this;
   }
 
   public function getBloggers() {
     return $this->assertAttached($this->bloggers);
   }
 
   public function getSkin() {
     $config = coalesce($this->getConfigData(), array());
     return idx($config, 'skin', self::SKIN_DEFAULT);
   }
 
   public function setSkin($skin) {
     $config = coalesce($this->getConfigData(), array());
     $config['skin'] = $skin;
     return $this->setConfigData($config);
   }
 
   static public function getSkinOptionsForSelect() {
     $classes = id(new PhutilSymbolLoader())
       ->setAncestorClass('PhameBlogSkin')
       ->setType('class')
       ->setConcreteOnly(true)
       ->selectSymbolsWithoutLoading();
 
     return ipull($classes, 'name', 'name');
   }
 
   public static function setRequestBlog(PhameBlog $blog) {
     self::$requestBlog = $blog;
   }
 
   public static function getRequestBlog() {
     return self::$requestBlog;
   }
 
   public function getLiveURI(PhamePost $post = null) {
     if ($this->getDomain()) {
       $base = new PhutilURI('http://'.$this->getDomain().'/');
     } else {
       $base = '/phame/live/'.$this->getID().'/';
       $base = PhabricatorEnv::getURI($base);
     }
 
     if ($post) {
       $base .= '/post/'.$post->getPhameTitle();
     }
 
     return $base;
   }
 
 
 /* -(  PhabricatorPolicyInterface Implementation  )-------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
       PhabricatorPolicyCapability::CAN_JOIN,
     );
   }
 
 
   public function getPolicy($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getViewPolicy();
       case PhabricatorPolicyCapability::CAN_EDIT:
         return $this->getEditPolicy();
       case PhabricatorPolicyCapability::CAN_JOIN:
         return $this->getJoinPolicy();
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $user) {
     $can_edit = PhabricatorPolicyCapability::CAN_EDIT;
     $can_join = PhabricatorPolicyCapability::CAN_JOIN;
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         // Users who can edit or post to a blog can always view it.
         if (PhabricatorPolicyFilter::hasCapability($user, $this, $can_edit)) {
           return true;
         }
         if (PhabricatorPolicyFilter::hasCapability($user, $this, $can_join)) {
           return true;
         }
         break;
       case PhabricatorPolicyCapability::CAN_JOIN:
         // Users who can edit a blog can always post to it.
         if (PhabricatorPolicyFilter::hasCapability($user, $this, $can_edit)) {
           return true;
         }
         break;
     }
 
     return false;
   }
 
 
   public function describeAutomaticCapability($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return pht(
           'Users who can edit or post on a blog can always view it.');
       case PhabricatorPolicyCapability::CAN_JOIN:
         return pht(
           'Users who can edit a blog can always post on it.');
     }
 
     return null;
   }
 
 
 /* -(  PhabricatorMarkupInterface Implementation  )-------------------------- */
 
 
   public function getMarkupFieldKey($field) {
     $hash = PhabricatorHash::digest($this->getMarkupText($field));
     return $this->getPHID().':'.$field.':'.$hash;
   }
 
 
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::newPhameMarkupEngine();
   }
 
 
   public function getMarkupText($field) {
     return $this->getDescription();
   }
 
 
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
     return $output;
   }
 
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getPHID();
   }
 
 }
diff --git a/src/applications/phame/storage/PhamePost.php b/src/applications/phame/storage/PhamePost.php
index ee98628e70..8c65ff26a3 100644
--- a/src/applications/phame/storage/PhamePost.php
+++ b/src/applications/phame/storage/PhamePost.php
@@ -1,256 +1,264 @@
 <?php
 
 final class PhamePost extends PhameDAO
   implements
     PhabricatorPolicyInterface,
     PhabricatorMarkupInterface,
     PhabricatorTokenReceiverInterface {
 
   const MARKUP_FIELD_BODY    = 'markup:body';
   const MARKUP_FIELD_SUMMARY = 'markup:summary';
 
   const VISIBILITY_DRAFT     = 0;
   const VISIBILITY_PUBLISHED = 1;
 
   protected $bloggerPHID;
   protected $title;
   protected $phameTitle;
   protected $body;
   protected $visibility;
   protected $configData;
   protected $datePublished;
   protected $blogPHID;
 
   private $blog;
 
   public static function initializePost(
     PhabricatorUser $blogger,
     PhameBlog $blog) {
 
     $post = id(new PhamePost())
       ->setBloggerPHID($blogger->getPHID())
       ->setBlogPHID($blog->getPHID())
       ->setBlog($blog)
       ->setDatePublished(0)
       ->setVisibility(self::VISIBILITY_DRAFT);
     return $post;
   }
 
   public function setBlog(PhameBlog $blog) {
     $this->blog = $blog;
     return $this;
   }
 
   public function getBlog() {
     return $this->blog;
   }
 
   public function getViewURI() {
     // go for the pretty uri if we can
     $domain = ($this->blog ? $this->blog->getDomain() : '');
     if ($domain) {
       $phame_title = PhabricatorSlug::normalize($this->getPhameTitle());
       return 'http://'.$domain.'/post/'.$phame_title;
     }
     $uri = '/phame/post/view/'.$this->getID().'/';
     return PhabricatorEnv::getProductionURI($uri);
   }
 
   public function getEditURI() {
     return '/phame/post/edit/'.$this->getID().'/';
   }
 
   public function isDraft() {
     return $this->getVisibility() == self::VISIBILITY_DRAFT;
   }
 
   public function getHumanName() {
     if ($this->isDraft()) {
       $name = 'draft';
     } else {
       $name = 'post';
     }
 
     return $name;
   }
 
   public function getCommentsWidget() {
     $config_data = $this->getConfigData();
     if (empty($config_data)) {
       return 'none';
     }
     return idx($config_data, 'comments_widget', 'none');
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID   => true,
       self::CONFIG_SERIALIZATION => array(
         'configData' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'title' => 'text255',
         'phameTitle' => 'text64',
-        'body' => 'text',
         'visibility' => 'uint32',
-        'datePublished' => 'epoch?',
+
+        // T6203/NULLABILITY
+        // These seem like they should always be non-null?
+        'blogPHID' => 'phid?',
+        'body' => 'text?',
+        'configData' => 'text?',
+
+        // T6203/NULLABILITY
+        // This one probably should be nullable?
+        'datePublished' => 'epoch',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'phameTitle' => array(
           'columns' => array('bloggerPHID', 'phameTitle'),
           'unique' => true,
         ),
         'bloggerPosts' => array(
           'columns' => array(
             'bloggerPHID',
             'visibility',
             'datePublished',
             'id',
           ),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       PhabricatorPhamePostPHIDType::TYPECONST);
   }
 
   public function toDictionary() {
     return array(
       'id'            => $this->getID(),
       'phid'          => $this->getPHID(),
       'blogPHID'      => $this->getBlogPHID(),
       'bloggerPHID'   => $this->getBloggerPHID(),
       'viewURI'       => $this->getViewURI(),
       'title'         => $this->getTitle(),
       'phameTitle'    => $this->getPhameTitle(),
       'body'          => $this->getBody(),
       'summary'       => PhabricatorMarkupEngine::summarize($this->getBody()),
       'datePublished' => $this->getDatePublished(),
       'published'     => !$this->isDraft(),
     );
   }
 
   public static function getVisibilityOptionsForSelect() {
     return array(
       self::VISIBILITY_DRAFT     => 'Draft: visible only to me.',
       self::VISIBILITY_PUBLISHED => 'Published: visible to the whole world.',
     );
   }
 
   public function getCommentsWidgetOptionsForSelect() {
     $current = $this->getCommentsWidget();
     $options = array();
 
     if ($current == 'facebook' ||
         PhabricatorFacebookAuthProvider::getFacebookApplicationID()) {
       $options['facebook'] = 'Facebook';
     }
     if ($current == 'disqus' ||
         PhabricatorEnv::getEnvConfig('disqus.shortname')) {
       $options['disqus'] = 'Disqus';
     }
     $options['none'] = 'None';
 
     return $options;
   }
 
 
 /* -(  PhabricatorPolicyInterface Implementation  )-------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
 
   public function getPolicy($capability) {
     // Draft posts are visible only to the author. Published posts are visible
     // to whoever the blog is visible to.
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         if (!$this->isDraft() && $this->getBlog()) {
           return $this->getBlog()->getViewPolicy();
         } else {
           return PhabricatorPolicies::POLICY_NOONE;
         }
         break;
       case PhabricatorPolicyCapability::CAN_EDIT:
         return PhabricatorPolicies::POLICY_NOONE;
     }
   }
 
 
   public function hasAutomaticCapability($capability, PhabricatorUser $user) {
     // A blog post's author can always view it, and is the only user allowed
     // to edit it.
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
       case PhabricatorPolicyCapability::CAN_EDIT:
         return ($user->getPHID() == $this->getBloggerPHID());
     }
   }
 
 
   public function describeAutomaticCapability($capability) {
     return pht(
       'The author of a blog post can always view and edit it.');
   }
 
 
 /* -(  PhabricatorMarkupInterface Implementation  )-------------------------- */
 
 
   public function getMarkupFieldKey($field) {
     $hash = PhabricatorHash::digest($this->getMarkupText($field));
     return $this->getPHID().':'.$field.':'.$hash;
   }
 
 
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::newPhameMarkupEngine();
   }
 
 
   public function getMarkupText($field) {
     switch ($field) {
       case self::MARKUP_FIELD_BODY:
         return $this->getBody();
       case self::MARKUP_FIELD_SUMMARY:
         return PhabricatorMarkupEngine::summarize($this->getBody());
     }
   }
 
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
     return $output;
   }
 
 
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getPHID();
   }
 
 /* -(  PhabricatorTokenReceiverInterface  )---------------------------------- */
 
   public function getUsersToNotifyOfTokenGiven() {
     return array(
       $this->getBloggerPHID(),
     );
   }
 
 }
diff --git a/src/applications/phriction/storage/PhrictionContent.php b/src/applications/phriction/storage/PhrictionContent.php
index f7b58f07eb..07ffc3347a 100644
--- a/src/applications/phriction/storage/PhrictionContent.php
+++ b/src/applications/phriction/storage/PhrictionContent.php
@@ -1,122 +1,125 @@
 <?php
 
 /**
  * @task markup Markup Interface
  */
 final class PhrictionContent extends PhrictionDAO
   implements PhabricatorMarkupInterface {
 
   const MARKUP_FIELD_BODY = 'markup:body';
 
   protected $id;
   protected $documentID;
   protected $version;
   protected $authorPHID;
 
   protected $title;
   protected $slug;
   protected $content;
   protected $description;
 
   protected $changeType;
   protected $changeRef;
 
   public function renderContent(PhabricatorUser $viewer) {
     return PhabricatorMarkupEngine::renderOneObject(
       $this,
       self::MARKUP_FIELD_BODY,
       $viewer);
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_COLUMN_SCHEMA => array(
         'version' => 'uint32',
         'title' => 'text',
         'slug' => 'text128',
         'content' => 'text',
-        'description' => 'text',
         'changeType' => 'uint32',
         'changeRef' => 'uint32?',
+
+        // T6203/NULLABILITY
+        // This should just be empty if not provided?
+        'description' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'documentID' => array(
           'columns' => array('documentID', 'version'),
           'unique' => true,
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID'),
         ),
         'slug' => array(
           'columns' => array('slug(255)'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
 
 /* -(  Markup Interface  )--------------------------------------------------- */
 
 
   /**
    * @task markup
    */
   public function getMarkupFieldKey($field) {
     if ($this->shouldUseMarkupCache($field)) {
       $id = $this->getID();
     } else {
       $id = PhabricatorHash::digest($this->getMarkupText($field));
     }
     return "phriction:{$field}:{$id}";
   }
 
 
   /**
    * @task markup
    */
   public function getMarkupText($field) {
     return $this->getContent();
   }
 
 
   /**
    * @task markup
    */
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::newPhrictionMarkupEngine();
   }
 
 
   /**
    * @task markup
    */
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
 
     $toc = PhutilRemarkupHeaderBlockRule::renderTableOfContents(
       $engine);
 
     if ($toc) {
       $toc = phutil_tag_div('phabricator-remarkup-toc', array(
         phutil_tag_div(
           'phabricator-remarkup-toc-header',
           pht('Table of Contents')),
         $toc,
       ));
     }
 
     return phutil_tag_div('phabricator-remarkup', array($toc, $output));
   }
 
 
   /**
    * @task markup
    */
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getID();
   }
 
 
 }
diff --git a/src/applications/ponder/storage/PonderAnswer.php b/src/applications/ponder/storage/PonderAnswer.php
index 4757dfbb28..a85aa6d3ad 100644
--- a/src/applications/ponder/storage/PonderAnswer.php
+++ b/src/applications/ponder/storage/PonderAnswer.php
@@ -1,233 +1,236 @@
 <?php
 
 final class PonderAnswer extends PonderDAO
   implements
     PhabricatorMarkupInterface,
     PonderVotableInterface,
     PhabricatorPolicyInterface,
     PhabricatorFlaggableInterface,
     PhabricatorSubscribableInterface,
     PhabricatorTokenReceiverInterface,
     PhabricatorDestructibleInterface {
 
   const MARKUP_FIELD_CONTENT = 'markup:content';
 
   protected $authorPHID;
   protected $questionID;
 
   protected $content;
   protected $contentSource;
 
   protected $voteCount;
   private $vote;
   private $question = self::ATTACHABLE;
   private $comments;
 
   private $userVotes = array();
 
   public function attachQuestion(PonderQuestion $question = null) {
     $this->question = $question;
     return $this;
   }
 
   public function getQuestion() {
     return $this->assertAttached($this->question);
   }
 
   public function getURI() {
     return '/Q'.$this->getQuestionID().'#A'.$this->getID();
   }
 
   public function setUserVote($vote) {
     $this->vote = $vote['data'];
     if (!$this->vote) {
       $this->vote = PonderVote::VOTE_NONE;
     }
     return $this;
   }
 
   public function attachUserVote($user_phid, $vote) {
     $this->vote = $vote;
     return $this;
   }
 
   public function getUserVote() {
     return $this->vote;
   }
 
   public function setComments($comments) {
     $this->comments = $comments;
     return $this;
   }
 
   public function getComments() {
     return $this->comments;
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
         'voteCount' => 'sint32',
         'content' => 'text',
-        'contentSource' => 'text',
+
+        // T6203/NULLABILITY
+        // This should always exist.
+        'contentSource' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'key_oneanswerperquestion' => array(
           'columns' => array('questionID', 'authorPHID'),
           'unique' => true,
         ),
         'questionID' => array(
           'columns' => array('questionID'),
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(PonderAnswerPHIDType::TYPECONST);
   }
 
   public function setContentSource(PhabricatorContentSource $content_source) {
     $this->contentSource = $content_source->serialize();
     return $this;
   }
 
   public function getContentSource() {
     return PhabricatorContentSource::newFromSerialized($this->contentSource);
   }
 
   public function getMarkupField() {
     return self::MARKUP_FIELD_CONTENT;
   }
 
   // Markup interface
 
   public function getMarkupFieldKey($field) {
     $hash = PhabricatorHash::digest($this->getMarkupText($field));
     $id = $this->getID();
     return "ponder:A{$id}:{$field}:{$hash}";
   }
 
   public function getMarkupText($field) {
     return $this->getContent();
   }
 
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::getEngine();
   }
 
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
     return $output;
   }
 
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getID();
   }
 
   // votable interface
   public function getUserVoteEdgeType() {
     return PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_ANSWER;
   }
 
   public function getVotablePHID() {
     return $this->getPHID();
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getQuestion()->getPolicy($capability);
       case PhabricatorPolicyCapability::CAN_EDIT:
         return PhabricatorPolicies::POLICY_NOONE;
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         if ($this->getAuthorPHID() == $viewer->getPHID()) {
           return true;
         }
         return $this->getQuestion()->hasAutomaticCapability(
           $capability,
           $viewer);
       case PhabricatorPolicyCapability::CAN_EDIT:
         return ($this->getAuthorPHID() == $viewer->getPHID());
     }
   }
 
 
   public function describeAutomaticCapability($capability) {
     $out = array();
     $out[] = pht('The author of an answer can always view and edit it.');
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         $out[] = pht(
           'The user who asks a question can always view the answers.');
         break;
     }
     return $out;
   }
 
 
 /* -(  PhabricatorTokenReceiverInterface  )---------------------------------- */
 
 
   public function getUsersToNotifyOfTokenGiven() {
     return array(
       $this->getAuthorPHID(),
     );
   }
 
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
 
   public function isAutomaticallySubscribed($phid) {
     return ($phid == $this->getAuthorPHID());
   }
 
   public function shouldShowSubscribersProperty() {
     return true;
   }
 
   public function shouldAllowSubscription($phid) {
     return true;
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
       $this->delete();
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/ponder/storage/PonderQuestion.php b/src/applications/ponder/storage/PonderQuestion.php
index 29f0da91ca..4db9118867 100644
--- a/src/applications/ponder/storage/PonderQuestion.php
+++ b/src/applications/ponder/storage/PonderQuestion.php
@@ -1,274 +1,277 @@
 <?php
 
 final class PonderQuestion extends PonderDAO
   implements
     PhabricatorMarkupInterface,
     PonderVotableInterface,
     PhabricatorSubscribableInterface,
     PhabricatorFlaggableInterface,
     PhabricatorPolicyInterface,
     PhabricatorTokenReceiverInterface,
     PhabricatorProjectInterface,
     PhabricatorDestructibleInterface {
 
   const MARKUP_FIELD_CONTENT = 'markup:content';
 
   protected $title;
   protected $phid;
 
   protected $authorPHID;
   protected $status;
   protected $content;
   protected $contentSource;
 
   protected $voteCount;
   protected $answerCount;
   protected $heat;
   protected $mailKey;
 
   private $answers;
   private $vote;
   private $comments;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_COLUMN_SCHEMA => array(
         'title' => 'text255',
         'voteCount' => 'sint32',
         'status' => 'uint32',
         'content' => 'text',
-        'contentSource' => 'text',
         'heat' => 'double',
         'answerCount' => 'uint32',
         'mailKey' => 'bytes20',
+
+        // T6203/NULLABILITY
+        // This should always exist.
+        'contentSource' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'authorPHID' => array(
           'columns' => array('authorPHID'),
         ),
         'heat' => array(
           'columns' => array('heat'),
         ),
         'status' => array(
           'columns' => array('status'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(PonderQuestionPHIDType::TYPECONST);
   }
 
   public function setContentSource(PhabricatorContentSource $content_source) {
     $this->contentSource = $content_source->serialize();
     return $this;
   }
 
   public function getContentSource() {
     return PhabricatorContentSource::newFromSerialized($this->contentSource);
   }
 
   public function attachVotes($user_phid) {
     $qa_phids = mpull($this->answers, 'getPHID') + array($this->getPHID());
 
     $edges = id(new PhabricatorEdgeQuery())
       ->withSourcePHIDs(array($user_phid))
       ->withDestinationPHIDs($qa_phids)
       ->withEdgeTypes(
         array(
           PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_QUESTION,
           PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_ANSWER
         ))
       ->needEdgeData(true)
       ->execute();
 
     $question_edge =
       $edges[$user_phid][PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_QUESTION];
     $answer_edges =
       $edges[$user_phid][PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_ANSWER];
     $edges = null;
 
     $this->setUserVote(idx($question_edge, $this->getPHID()));
     foreach ($this->answers as $answer) {
       $answer->setUserVote(idx($answer_edges, $answer->getPHID()));
     }
   }
 
   public function setUserVote($vote) {
     $this->vote = $vote['data'];
     if (!$this->vote) {
       $this->vote = PonderVote::VOTE_NONE;
     }
     return $this;
   }
 
   public function attachUserVote($user_phid, $vote) {
     $this->vote = $vote;
     return $this;
   }
 
   public function getUserVote() {
     return $this->vote;
   }
 
   public function setComments($comments) {
     $this->comments = $comments;
     return $this;
   }
 
   public function getComments() {
     return $this->comments;
   }
 
   public function attachAnswers(array $answers) {
     assert_instances_of($answers, 'PonderAnswer');
     $this->answers = $answers;
     return $this;
   }
 
   public function getAnswers() {
     return $this->answers;
   }
 
   public function getMarkupField() {
     return self::MARKUP_FIELD_CONTENT;
   }
 
   // Markup interface
 
   public function getMarkupFieldKey($field) {
     $hash = PhabricatorHash::digest($this->getMarkupText($field));
     $id = $this->getID();
     return "ponder:Q{$id}:{$field}:{$hash}";
   }
 
   public function getMarkupText($field) {
     return $this->getContent();
   }
 
   public function newMarkupEngine($field) {
     return PhabricatorMarkupEngine::getEngine();
   }
 
   public function didMarkupText(
     $field,
     $output,
     PhutilMarkupEngine $engine) {
     return $output;
   }
 
   public function shouldUseMarkupCache($field) {
     return (bool)$this->getID();
   }
 
   // votable interface
   public function getUserVoteEdgeType() {
     return PhabricatorEdgeConfig::TYPE_VOTING_USER_HAS_QUESTION;
   }
 
   public function getVotablePHID() {
     return $this->getPHID();
   }
 
   public function save() {
     if (!$this->getMailKey()) {
       $this->setMailKey(Filesystem::readRandomCharacters(20));
     }
     return parent::save();
   }
 
   public function getOriginalTitle() {
     // TODO: Make this actually save/return the original title.
     return $this->getTitle();
   }
 
   public function getFullTitle() {
     $id = $this->getID();
     $title = $this->getTitle();
     return "Q{$id}: {$title}";
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     $policy = PhabricatorPolicies::POLICY_NOONE;
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         $policy = PhabricatorPolicies::POLICY_USER;
         break;
     }
 
     return $policy;
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return ($viewer->getPHID() == $this->getAuthorPHID());
   }
 
 
   public function describeAutomaticCapability($capability) {
     return pht(
       'The user who asked a question can always view and edit it.');
   }
 
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
 
   public function isAutomaticallySubscribed($phid) {
     return ($phid == $this->getAuthorPHID());
   }
 
   public function shouldShowSubscribersProperty() {
     return true;
   }
 
   public function shouldAllowSubscription($phid) {
     return true;
   }
 
 
 /* -(  PhabricatorTokenReceiverInterface  )---------------------------------- */
 
 
   public function getUsersToNotifyOfTokenGiven() {
     return array(
       $this->getAuthorPHID(),
     );
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
       $answers = id(new PonderAnswer())->loadAllWhere(
         'questionID = %d',
         $this->getID());
       foreach ($answers as $answer) {
         $engine->destroyObject($answer);
       }
 
       $this->delete();
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/project/storage/PhabricatorProject.php b/src/applications/project/storage/PhabricatorProject.php
index afacd65fcf..3617ad12e0 100644
--- a/src/applications/project/storage/PhabricatorProject.php
+++ b/src/applications/project/storage/PhabricatorProject.php
@@ -1,367 +1,372 @@
 <?php
 
 final class PhabricatorProject extends PhabricatorProjectDAO
   implements
     PhabricatorFlaggableInterface,
     PhabricatorPolicyInterface,
     PhabricatorSubscribableInterface,
     PhabricatorCustomFieldInterface,
     PhabricatorDestructibleInterface {
 
   protected $name;
   protected $status = PhabricatorProjectStatus::STATUS_ACTIVE;
   protected $authorPHID;
   protected $subprojectPHIDs = array();
   protected $phrictionSlug;
   protected $profileImagePHID;
   protected $icon;
   protected $color;
 
   protected $viewPolicy;
   protected $editPolicy;
   protected $joinPolicy;
   protected $isMembershipLocked;
 
   private $memberPHIDs = self::ATTACHABLE;
   private $watcherPHIDs = self::ATTACHABLE;
   private $sparseWatchers = self::ATTACHABLE;
   private $sparseMembers = self::ATTACHABLE;
   private $customFields = self::ATTACHABLE;
   private $profileImageFile = self::ATTACHABLE;
   private $slugs = self::ATTACHABLE;
 
   const DEFAULT_ICON = 'fa-briefcase';
   const DEFAULT_COLOR = 'blue';
 
   const TABLE_DATASOURCE_TOKEN = 'project_datasourcetoken';
 
   public static function initializeNewProject(PhabricatorUser $actor) {
     return id(new PhabricatorProject())
       ->setName('')
       ->setAuthorPHID($actor->getPHID())
       ->setIcon(self::DEFAULT_ICON)
       ->setColor(self::DEFAULT_COLOR)
       ->setViewPolicy(PhabricatorPolicies::POLICY_USER)
       ->setEditPolicy(PhabricatorPolicies::POLICY_USER)
       ->setJoinPolicy(PhabricatorPolicies::POLICY_USER)
       ->setIsMembershipLocked(0)
       ->attachMemberPHIDs(array());
   }
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
       PhabricatorPolicyCapability::CAN_JOIN,
     );
   }
 
   public function getPolicy($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getViewPolicy();
       case PhabricatorPolicyCapability::CAN_EDIT:
         return $this->getEditPolicy();
       case PhabricatorPolicyCapability::CAN_JOIN:
         return $this->getJoinPolicy();
     }
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
 
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         if ($this->isUserMember($viewer->getPHID())) {
           // Project members can always view a project.
           return true;
         }
         break;
       case PhabricatorPolicyCapability::CAN_EDIT:
         break;
       case PhabricatorPolicyCapability::CAN_JOIN:
         $can_edit = PhabricatorPolicyCapability::CAN_EDIT;
         if (PhabricatorPolicyFilter::hasCapability($viewer, $this, $can_edit)) {
           // Project editors can always join a project.
           return true;
         }
         break;
     }
 
     return false;
   }
 
   public function describeAutomaticCapability($capability) {
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return pht('Members of a project can always view it.');
       case PhabricatorPolicyCapability::CAN_JOIN:
         return pht('Users who can edit a project can always join it.');
     }
     return null;
   }
 
   public function isUserMember($user_phid) {
     if ($this->memberPHIDs !== self::ATTACHABLE) {
       return in_array($user_phid, $this->memberPHIDs);
     }
     return $this->assertAttachedKey($this->sparseMembers, $user_phid);
   }
 
   public function setIsUserMember($user_phid, $is_member) {
     if ($this->sparseMembers === self::ATTACHABLE) {
       $this->sparseMembers = array();
     }
     $this->sparseMembers[$user_phid] = $is_member;
     return $this;
   }
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'subprojectPHIDs' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'name' => 'text255',
         'status' => 'text32',
         'phrictionSlug' => 'text128?',
-        'joinPolicy' => 'policy',
         'isMembershipLocked' => 'bool',
         'profileImagePHID' => 'phid?',
         'icon' => 'text32',
         'color' => 'text32',
+
+        // T6203/NULLABILITY
+        // These are definitely wrong and should always exist.
+        'editPolicy' => 'policy?',
+        'viewPolicy' => 'policy?',
+        'joinPolicy' => 'policy?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'key_icon' => array(
           'columns' => array('icon'),
         ),
         'key_color' => array(
           'columns' => array('color'),
         ),
         'phrictionSlug' => array(
           'columns' => array('phrictionSlug'),
           'unique' => true,
         ),
         'name' => array(
           'columns' => array('name'),
           'unique' => true,
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       PhabricatorProjectProjectPHIDType::TYPECONST);
   }
 
   public function attachMemberPHIDs(array $phids) {
     $this->memberPHIDs = $phids;
     return $this;
   }
 
   public function getMemberPHIDs() {
     return $this->assertAttached($this->memberPHIDs);
   }
 
   public function setPhrictionSlug($slug) {
 
     // NOTE: We're doing a little magic here and stripping out '/' so that
     // project pages always appear at top level under projects/ even if the
     // display name is "Hack / Slash" or similar (it will become
     // 'hack_slash' instead of 'hack/slash').
 
     $slug = str_replace('/', ' ', $slug);
     $slug = PhabricatorSlug::normalize($slug);
     $this->phrictionSlug = $slug;
     return $this;
   }
 
   public function getFullPhrictionSlug() {
     $slug = $this->getPhrictionSlug();
     return 'projects/'.$slug;
   }
 
   // TODO - once we sever project => phriction automagicalness,
   // migrate getPhrictionSlug to have no trailing slash and be called
   // getPrimarySlug
   public function getPrimarySlug() {
     $slug = $this->getPhrictionSlug();
     return rtrim($slug, '/');
   }
 
   public function isArchived() {
     return ($this->getStatus() == PhabricatorProjectStatus::STATUS_ARCHIVED);
   }
 
   public function getProfileImageURI() {
     return $this->getProfileImageFile()->getBestURI();
   }
 
   public function attachProfileImageFile(PhabricatorFile $file) {
     $this->profileImageFile = $file;
     return $this;
   }
 
   public function getProfileImageFile() {
     return $this->assertAttached($this->profileImageFile);
   }
 
 
   public function isUserWatcher($user_phid) {
     if ($this->watcherPHIDs !== self::ATTACHABLE) {
       return in_array($user_phid, $this->watcherPHIDs);
     }
     return $this->assertAttachedKey($this->sparseWatchers, $user_phid);
   }
 
   public function setIsUserWatcher($user_phid, $is_watcher) {
     if ($this->sparseWatchers === self::ATTACHABLE) {
       $this->sparseWatchers = array();
     }
     $this->sparseWatchers[$user_phid] = $is_watcher;
     return $this;
   }
 
   public function attachWatcherPHIDs(array $phids) {
     $this->watcherPHIDs = $phids;
     return $this;
   }
 
   public function getWatcherPHIDs() {
     return $this->assertAttached($this->watcherPHIDs);
   }
 
   public function attachSlugs(array $slugs) {
     $this->slugs = $slugs;
     return $this;
   }
 
   public function getSlugs() {
     return $this->assertAttached($this->slugs);
   }
 
   public function getColor() {
     if ($this->isArchived()) {
       return PHUITagView::COLOR_DISABLED;
     }
 
     return $this->color;
   }
 
   public function save() {
     $this->openTransaction();
       $result = parent::save();
       $this->updateDatasourceTokens();
     $this->saveTransaction();
 
     return $result;
   }
 
   public function updateDatasourceTokens() {
     $table = self::TABLE_DATASOURCE_TOKEN;
     $conn_w = $this->establishConnection('w');
     $id = $this->getID();
 
     $slugs = queryfx_all(
       $conn_w,
       'SELECT * FROM %T WHERE projectPHID = %s',
       id(new PhabricatorProjectSlug())->getTableName(),
       $this->getPHID());
 
     $all_strings = ipull($slugs, 'slug');
     $all_strings[] = $this->getName();
     $all_strings = implode(' ', $all_strings);
 
     $tokens = PhabricatorTypeaheadDatasource::tokenizeString($all_strings);
 
     $sql = array();
     foreach ($tokens as $token) {
       $sql[] = qsprintf($conn_w, '(%d, %s)', $id, $token);
     }
 
     $this->openTransaction();
       queryfx(
         $conn_w,
         'DELETE FROM %T WHERE projectID = %d',
         $table,
         $id);
 
       foreach (PhabricatorLiskDAO::chunkSQL($sql) as $chunk) {
         queryfx(
           $conn_w,
           'INSERT INTO %T (projectID, token) VALUES %Q',
           $table,
           $chunk);
       }
     $this->saveTransaction();
   }
 
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
 
   public function isAutomaticallySubscribed($phid) {
     return false;
   }
 
   public function shouldShowSubscribersProperty() {
     return false;
   }
 
   public function shouldAllowSubscription($phid) {
     return $this->isUserMember($phid) &&
            !$this->isUserWatcher($phid);
   }
 
 
 /* -(  PhabricatorCustomFieldInterface  )------------------------------------ */
 
 
   public function getCustomFieldSpecificationForRole($role) {
     return PhabricatorEnv::getEnvConfig('projects.fields');
   }
 
   public function getCustomFieldBaseClass() {
     return 'PhabricatorProjectCustomField';
   }
 
   public function getCustomFields() {
     return $this->assertAttached($this->customFields);
   }
 
   public function attachCustomFields(PhabricatorCustomFieldAttachment $fields) {
     $this->customFields = $fields;
     return $this;
   }
 
 
 /* -(  PhabricatorDestructibleInterface  )----------------------------------- */
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
 
     $this->openTransaction();
       $this->delete();
 
       $columns = id(new PhabricatorProjectColumn())
         ->loadAllWhere('projectPHID = %s', $this->getPHID());
       foreach ($columns as $column) {
         $engine->destroyObject($column);
       }
 
       $slugs = id(new PhabricatorProjectSlug())
         ->loadAllWhere('projectPHID = %s', $this->getPHID());
       foreach ($slugs as $slug) {
         $slug->delete();
       }
 
     $this->saveTransaction();
   }
 
 }
diff --git a/src/applications/releeph/storage/ReleephRequest.php b/src/applications/releeph/storage/ReleephRequest.php
index 8159af0479..54976ae451 100644
--- a/src/applications/releeph/storage/ReleephRequest.php
+++ b/src/applications/releeph/storage/ReleephRequest.php
@@ -1,344 +1,346 @@
 <?php
 
 final class ReleephRequest extends ReleephDAO
   implements
     PhabricatorPolicyInterface,
     PhabricatorCustomFieldInterface {
 
   protected $branchID;
   protected $requestUserPHID;
   protected $details = array();
   protected $userIntents = array();
   protected $inBranch;
   protected $pickStatus;
   protected $mailKey;
 
   /**
    * The object which is being requested. Normally this is a commit, but it
    * might also be a revision. In the future, it could be a repository branch
    * or an external object (like a GitHub pull request).
    */
   protected $requestedObjectPHID;
 
   // Information about the thing being requested
   protected $requestCommitPHID;
 
   // Information about the last commit to the releeph branch
   protected $commitIdentifier;
   protected $commitPHID;
 
 
   private $customFields = self::ATTACHABLE;
   private $branch = self::ATTACHABLE;
   private $requestedObject = self::ATTACHABLE;
 
 
 /* -(  Constants and helper methods  )--------------------------------------- */
 
   const INTENT_WANT = 'want';
   const INTENT_PASS = 'pass';
 
   const PICK_PENDING  = 1; // old
   const PICK_FAILED   = 2;
   const PICK_OK       = 3;
   const PICK_MANUAL   = 4; // old
   const REVERT_OK     = 5;
   const REVERT_FAILED = 6;
 
   public function shouldBeInBranch() {
     return
       $this->getPusherIntent() == self::INTENT_WANT &&
       /**
        * We use "!= pass" instead of "== want" in case the requestor intent is
        * not present. In other words, only revert if the requestor explicitly
        * passed.
        */
       $this->getRequestorIntent() != self::INTENT_PASS;
   }
 
   /**
    * Will return INTENT_WANT if any pusher wants this request, and no pusher
    * passes on this request.
    */
   public function getPusherIntent() {
     $product = $this->getBranch()->getProduct();
 
     if (!$product->getPushers()) {
       return self::INTENT_WANT;
     }
 
     $found_pusher_want = false;
     foreach ($this->userIntents as $phid => $intent) {
       if ($product->isAuthoritativePHID($phid)) {
         if ($intent == self::INTENT_PASS) {
           return self::INTENT_PASS;
         }
 
         $found_pusher_want = true;
       }
     }
 
     if ($found_pusher_want) {
       return self::INTENT_WANT;
     } else {
       return null;
     }
   }
 
   public function getRequestorIntent() {
     return idx($this->userIntents, $this->requestUserPHID);
   }
 
   public function getStatus() {
     return $this->calculateStatus();
   }
 
   public function getMonogram() {
     return 'Y'.$this->getID();
   }
 
   public function getBranch() {
     return $this->assertAttached($this->branch);
   }
 
   public function attachBranch(ReleephBranch $branch) {
     $this->branch = $branch;
     return $this;
   }
 
   public function getRequestedObject() {
     return $this->assertAttached($this->requestedObject);
   }
 
   public function attachRequestedObject($object) {
     $this->requestedObject = $object;
     return $this;
   }
 
   private function calculateStatus() {
     if ($this->shouldBeInBranch()) {
       if ($this->getInBranch()) {
         return ReleephRequestStatus::STATUS_PICKED;
       } else {
         return ReleephRequestStatus::STATUS_NEEDS_PICK;
       }
     } else {
       if ($this->getInBranch()) {
         return ReleephRequestStatus::STATUS_NEEDS_REVERT;
       } else {
         $has_been_in_branch = $this->getCommitIdentifier();
         // Regardless of why we reverted something, always say reverted if it
         // was once in the branch.
         if ($has_been_in_branch) {
           return ReleephRequestStatus::STATUS_REVERTED;
         } else if ($this->getPusherIntent() === ReleephRequest::INTENT_PASS) {
           // Otherwise, if it has never been in the branch, explicitly say why:
           return ReleephRequestStatus::STATUS_REJECTED;
         } else if ($this->getRequestorIntent() === ReleephRequest::INTENT_WANT) {
           return ReleephRequestStatus::STATUS_REQUESTED;
         } else {
           return ReleephRequestStatus::STATUS_ABANDONED;
         }
       }
     }
   }
 
 
 /* -(  Lisk mechanics  )----------------------------------------------------- */
 
   public function getConfiguration() {
     return array(
       self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'details' => self::SERIALIZATION_JSON,
         'userIntents' => self::SERIALIZATION_JSON,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'requestCommitPHID' => 'phid?',
-        'commitIdentifier' => 'text40',
-        'pickStatus' => 'uint32',
+        'commitIdentifier' => 'text40?',
+        'commitPHID' => 'phid?',
+        'pickStatus' => 'uint32?',
         'inBranch' => 'bool',
         'mailKey' => 'bytes20',
+        'userIntents' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
         'phid' => array(
           'columns' => array('phid'),
           'unique' => true,
         ),
         'requestIdentifierBranch' => array(
           'columns' => array('requestCommitPHID', 'branchID'),
           'unique' => true,
         ),
         'branchID' => array(
           'columns' => array('branchID'),
         ),
         'key_requestedObject' => array(
           'columns' => array('requestedObjectPHID'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function generatePHID() {
     return PhabricatorPHID::generateNewPHID(
       ReleephRequestPHIDType::TYPECONST);
   }
 
   public function save() {
     if (!$this->getMailKey()) {
       $this->setMailKey(Filesystem::readRandomCharacters(20));
     }
     return parent::save();
   }
 
 
 /* -(  Helpful accessors )--------------------------------------------------- */
 
 
   public function getDetail($key, $default = null) {
     return idx($this->getDetails(), $key, $default);
   }
 
   public function setDetail($key, $value) {
     $this->details[$key] = $value;
     return $this;
   }
 
 
   /**
    * Get the commit PHIDs this request is requesting.
    *
    * NOTE: For now, this always returns one PHID.
    *
    * @return list<phid> Commit PHIDs requested by this request.
    */
   public function getCommitPHIDs() {
     return array(
       $this->requestCommitPHID,
     );
   }
 
   public function getReason() {
     // Backward compatibility: reason used to be called comments
     $reason = $this->getDetail('reason');
     if (!$reason) {
       return $this->getDetail('comments');
     }
     return $reason;
   }
 
   /**
    * Allow a null summary, and fall back to the title of the commit.
    */
   public function getSummaryForDisplay() {
     $summary = $this->getDetail('summary');
 
     if (!strlen($summary)) {
       $commit = $this->loadPhabricatorRepositoryCommit();
       if ($commit) {
         $summary = $commit->getSummary();
       }
     }
 
     if (!strlen($summary)) {
       $summary = pht('None');
     }
 
     return $summary;
   }
 
 /* -(  Loading external objects  )------------------------------------------- */
 
   public function loadPhabricatorRepositoryCommit() {
     return $this->loadOneRelative(
       new PhabricatorRepositoryCommit(),
       'phid',
       'getRequestCommitPHID');
   }
 
   public function loadPhabricatorRepositoryCommitData() {
     $commit = $this->loadPhabricatorRepositoryCommit();
     if ($commit) {
       return $commit->loadOneRelative(
         new PhabricatorRepositoryCommitData(),
         'commitID');
     }
   }
 
 
 /* -(  State change helpers  )----------------------------------------------- */
 
   public function setUserIntent(PhabricatorUser $user, $intent) {
     $this->userIntents[$user->getPHID()] = $intent;
     return $this;
   }
 
 
 /* -(  Migrating to status-less ReleephRequests  )--------------------------- */
 
   protected function didReadData() {
     if ($this->userIntents === null) {
       $this->userIntents = array();
     }
   }
 
   public function setStatus($value) {
     throw new Exception('`status` is now deprecated!');
   }
 
 /* -(  Make magic Lisk methods private  )------------------------------------ */
 
   private function setUserIntents(array $ar) {
     return parent::setUserIntents($ar);
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getBranch()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getBranch()->hasAutomaticCapability($capability, $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return pht(
       'Pull requests have the same policies as the branches they are '.
       'requested against.');
   }
 
 
 
 /* -(  PhabricatorCustomFieldInterface  )------------------------------------ */
 
 
   public function getCustomFieldSpecificationForRole($role) {
     return PhabricatorEnv::getEnvConfig('releeph.fields');
   }
 
   public function getCustomFieldBaseClass() {
     return 'ReleephFieldSpecification';
   }
 
   public function getCustomFields() {
     return $this->assertAttached($this->customFields);
   }
 
   public function attachCustomFields(PhabricatorCustomFieldAttachment $fields) {
     $this->customFields = $fields;
     return $this;
   }
 
 
 }
diff --git a/src/applications/repository/storage/PhabricatorRepositoryRefCursor.php b/src/applications/repository/storage/PhabricatorRepositoryRefCursor.php
index 7a9acb9912..699108f7b8 100644
--- a/src/applications/repository/storage/PhabricatorRepositoryRefCursor.php
+++ b/src/applications/repository/storage/PhabricatorRepositoryRefCursor.php
@@ -1,89 +1,92 @@
 <?php
 
 /**
  * Stores the previous value of a ref (like a branch or tag) so we can figure
  * out how a repository has changed when we discover new commits or branch
  * heads.
  */
 final class PhabricatorRepositoryRefCursor extends PhabricatorRepositoryDAO
   implements PhabricatorPolicyInterface {
 
   const TYPE_BRANCH = 'branch';
   const TYPE_TAG = 'tag';
   const TYPE_BOOKMARK = 'bookmark';
 
   protected $repositoryPHID;
   protected $refType;
   protected $refNameHash;
   protected $refNameRaw;
   protected $refNameEncoding;
   protected $commitIdentifier;
 
   private $repository = self::ATTACHABLE;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_TIMESTAMPS => false,
       self::CONFIG_BINARY => array(
         'refNameRaw' => true,
       ),
       self::CONFIG_COLUMN_SCHEMA => array(
         'refType' => 'text32',
         'refNameHash' => 'bytes12',
-        'refNameEncoding' => 'text16',
         'commitIdentifier' => 'text40',
+
+        // T6203/NULLABILITY
+        // This probably should not be nullable; refNameRaw is not nullable.
+        'refNameEncoding' => 'text16?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_cursor' => array(
           'columns' => array('repositoryPHID', 'refType', 'refNameHash'),
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function getRefName() {
     return $this->getUTF8StringFromStorage(
       $this->getRefNameRaw(),
       $this->getRefNameEncoding());
   }
 
   public function setRefName($ref_raw) {
     $this->setRefNameRaw($ref_raw);
     $this->setRefNameHash(PhabricatorHash::digestForIndex($ref_raw));
     $this->setRefNameEncoding($this->detectEncodingForStorage($ref_raw));
 
     return $this;
   }
 
   public function attachRepository(PhabricatorRepository $repository) {
     $this->repository = $repository;
     return $this;
   }
 
   public function getRepository() {
     return $this->assertAttached($this->repository);
   }
 
 
 /* -(  PhabricatorPolicyInterface  )----------------------------------------- */
 
 
   public function getCapabilities() {
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
     );
   }
 
   public function getPolicy($capability) {
     return $this->getRepository()->getPolicy($capability);
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
     return $this->getRepository()->hasAutomaticCapability($capability, $viewer);
   }
 
   public function describeAutomaticCapability($capability) {
     return pht('Repository refs have the same policies as their repository.');
   }
 
 }
diff --git a/src/applications/settings/storage/PhabricatorUserSSHKey.php b/src/applications/settings/storage/PhabricatorUserSSHKey.php
index 2720ecb19f..250250a84f 100644
--- a/src/applications/settings/storage/PhabricatorUserSSHKey.php
+++ b/src/applications/settings/storage/PhabricatorUserSSHKey.php
@@ -1,42 +1,45 @@
 <?php
 
 final class PhabricatorUserSSHKey extends PhabricatorUserDAO {
 
   protected $userPHID;
   protected $name;
   protected $keyType;
   protected $keyBody;
   protected $keyHash;
   protected $keyComment;
 
   public function getConfiguration() {
     return array(
       self::CONFIG_COLUMN_SCHEMA => array(
-        'name' => 'text255',
-        'keyType' => 'text255',
-        'keyBody' => 'text',
         'keyHash' => 'bytes32',
         'keyComment' => 'text255?',
+
+        // T6203/NULLABILITY
+        // These seem like they should not be nullable.
+        'name' => 'text255?',
+        'keyType' => 'text255?',
+        'keyBody' => 'text?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'userPHID' => array(
           'columns' => array('userPHID'),
         ),
         'keyHash' => array(
           'columns' => array('keyHash'),
           'unique' => true,
         ),
       ),
     ) + parent::getConfiguration();
   }
 
   public function getEntireKey() {
     $parts = array(
       $this->getKeyType(),
       $this->getKeyBody(),
       $this->getKeyComment(),
     );
     return trim(implode(' ', $parts));
   }
 
 }
diff --git a/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php b/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php
index 20e3c0d109..8870d9e203 100644
--- a/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php
+++ b/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php
@@ -1,200 +1,207 @@
 <?php
 
 final class PhabricatorWorkerActiveTask extends PhabricatorWorkerTask {
 
   protected $failureTime;
 
   private $serverTime;
   private $localTime;
 
   public function getConfiguration() {
     $parent = parent::getConfiguration();
 
     $config = array(
       self::CONFIG_IDS => self::IDS_COUNTER,
       self::CONFIG_TIMESTAMPS => false,
       self::CONFIG_KEY_SCHEMA => array(
         'dataID' => array(
           'columns' => array('dataID'),
           'unique' => true,
         ),
         'taskClass' => array(
           'columns' => array('taskClass'),
         ),
         'leaseExpires' => array(
           'columns' => array('leaseExpires'),
         ),
         'leaseOwner' => array(
           'columns' => array('leaseOwner(16)'),
         ),
         'key_failuretime' => array(
           'columns' => array('failureTime'),
         ),
         'leaseOwner_2' => array(
           'columns' => array('leaseOwner', 'priority', 'id'),
         ),
       ),
     );
 
+    $config[self::CONFIG_COLUMN_SCHEMA] = array(
+      // T6203/NULLABILITY
+      // This isn't nullable in the archive table, so at a minimum these
+      // should be the same.
+      'dataID' => 'uint32?',
+    ) + $parent[self::CONFIG_COLUMN_SCHEMA];
+
     return $config + $parent;
   }
 
   public function setServerTime($server_time) {
     $this->serverTime = $server_time;
     $this->localTime = time();
     return $this;
   }
 
   public function setLeaseDuration($lease_duration) {
     $this->checkLease();
     $server_lease_expires = $this->serverTime + $lease_duration;
     $this->setLeaseExpires($server_lease_expires);
 
     // NOTE: This is primarily to allow unit tests to set negative lease
     // durations so they don't have to wait around for leases to expire. We
     // check that the lease is valid above.
     return $this->forceSaveWithoutLease();
   }
 
   public function save() {
     $this->checkLease();
     return $this->forceSaveWithoutLease();
   }
 
   public function forceSaveWithoutLease() {
     $is_new = !$this->getID();
     if ($is_new) {
       $this->failureCount = 0;
     }
 
     if ($is_new && ($this->getData() !== null)) {
       $data = new PhabricatorWorkerTaskData();
       $data->setData($this->getData());
       $data->save();
 
       $this->setDataID($data->getID());
     }
 
     return parent::save();
   }
 
   protected function checkLease() {
     if ($this->leaseOwner) {
       $current_server_time = $this->serverTime + (time() - $this->localTime);
       if ($current_server_time >= $this->leaseExpires) {
         $id = $this->getID();
         $class = $this->getTaskClass();
         throw new Exception(
           "Trying to update Task {$id} ({$class}) after lease expiration!");
       }
     }
   }
 
   public function delete() {
     throw new Exception(
       'Active tasks can not be deleted directly. '.
       'Use archiveTask() to move tasks to the archive.');
   }
 
   public function archiveTask($result, $duration) {
     if ($this->getID() === null) {
       throw new Exception(
         "Attempting to archive a task which hasn't been save()d!");
     }
 
     $this->checkLease();
 
     $archive = id(new PhabricatorWorkerArchiveTask())
       ->setID($this->getID())
       ->setTaskClass($this->getTaskClass())
       ->setLeaseOwner($this->getLeaseOwner())
       ->setLeaseExpires($this->getLeaseExpires())
       ->setFailureCount($this->getFailureCount())
       ->setDataID($this->getDataID())
       ->setPriority($this->getPriority())
       ->setResult($result)
       ->setDuration($duration);
 
     // NOTE: This deletes the active task (this object)!
     $archive->save();
 
     return $archive;
   }
 
   public function executeTask() {
     // We do this outside of the try .. catch because we don't have permission
     // to release the lease otherwise.
     $this->checkLease();
 
     $did_succeed = false;
     try {
       $worker = $this->getWorkerInstance();
 
       $maximum_failures = $worker->getMaximumRetryCount();
       if ($maximum_failures !== null) {
         if ($this->getFailureCount() > $maximum_failures) {
           $id = $this->getID();
           throw new PhabricatorWorkerPermanentFailureException(
             "Task {$id} has exceeded the maximum number of failures ".
             "({$maximum_failures}).");
         }
       }
 
       $lease = $worker->getRequiredLeaseTime();
       if ($lease !== null) {
         $this->setLeaseDuration($lease);
       }
 
       $t_start = microtime(true);
         $worker->executeTask();
       $t_end = microtime(true);
       $duration = (int)(1000000 * ($t_end - $t_start));
 
       $result = $this->archiveTask(
         PhabricatorWorkerArchiveTask::RESULT_SUCCESS,
         $duration);
       $did_succeed = true;
     } catch (PhabricatorWorkerPermanentFailureException $ex) {
       $result = $this->archiveTask(
         PhabricatorWorkerArchiveTask::RESULT_FAILURE,
         0);
       $result->setExecutionException($ex);
     } catch (PhabricatorWorkerYieldException $ex) {
       $this->setExecutionException($ex);
 
       $retry = $ex->getDuration();
       $retry = max($retry, 5);
 
       // NOTE: As a side effect, this saves the object.
       $this->setLeaseDuration($retry);
 
       $result = $this;
     } catch (Exception $ex) {
       $this->setExecutionException($ex);
       $this->setFailureCount($this->getFailureCount() + 1);
       $this->setFailureTime(time());
 
       $retry = $worker->getWaitBeforeRetry($this);
       $retry = coalesce(
         $retry,
         PhabricatorWorkerLeaseQuery::getDefaultWaitBeforeRetry());
 
       // NOTE: As a side effect, this saves the object.
       $this->setLeaseDuration($retry);
 
       $result = $this;
     }
 
     // NOTE: If this throws, we don't want it to cause the task to fail again,
     // so execute it out here and just let the exception escape.
     if ($did_succeed) {
       foreach ($worker->getQueuedTasks() as $task) {
         list($class, $data) = $task;
         PhabricatorWorker::scheduleTask($class, $data, $this->getPriority());
       }
     }
 
     return $result;
   }
 
 }