diff --git a/resources/sql/autopatches/20140722.audit.1.xactions.sql b/resources/sql/autopatches/20140722.audit.1.xactions.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20140722.audit.1.xactions.sql
@@ -0,0 +1,19 @@
+CREATE TABLE {$NAMESPACE}_audit.audit_transaction (
+  id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  phid VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  authorPHID VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  objectPHID VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  viewPolicy VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  editPolicy VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  commentPHID VARCHAR(64) COLLATE utf8_bin DEFAULT NULL,
+  commentVersion INT UNSIGNED NOT NULL,
+  transactionType VARCHAR(32) COLLATE utf8_bin NOT NULL,
+  oldValue LONGTEXT COLLATE utf8_bin NOT NULL,
+  newValue LONGTEXT COLLATE utf8_bin NOT NULL,
+  contentSource LONGTEXT COLLATE utf8_bin NOT NULL,
+  metadata LONGTEXT COLLATE utf8_bin NOT NULL,
+  dateCreated INT UNSIGNED NOT NULL,
+  dateModified INT UNSIGNED NOT NULL,
+  UNIQUE KEY `key_phid` (`phid`),
+  KEY `key_object` (`objectPHID`)
+) ENGINE=InnoDB, COLLATE utf8_general_ci;
diff --git a/resources/sql/autopatches/20140722.audit.2.comments.sql b/resources/sql/autopatches/20140722.audit.2.comments.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20140722.audit.2.comments.sql
@@ -0,0 +1,29 @@
+CREATE TABLE {$NAMESPACE}_audit.audit_transaction_comment (
+  id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  phid VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  transactionPHID VARCHAR(64) COLLATE utf8_bin,
+  authorPHID VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  viewPolicy VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  editPolicy VARCHAR(64) COLLATE utf8_bin NOT NULL,
+  commentVersion INT UNSIGNED NOT NULL,
+  content longtext COLLATE utf8_bin NOT NULL,
+  contentSource longtext COLLATE utf8_bin NOT NULL,
+  isDeleted BOOL NOT NULL,
+  dateCreated INT UNSIGNED NOT NULL,
+  dateModified INT UNSIGNED NOT NULL,
+  commitPHID VARCHAR(64) COLLATE utf8_bin,
+  pathID INT UNSIGNED,
+  isNewFile BOOL NOT NULL,
+  lineNumber INT UNSIGNED NOT NULL,
+  lineLength INT UNSIGNED NOT NULL,
+  fixedState VARCHAR(12) COLLATE utf8_bin,
+  hasReplies BOOL NOT NULL,
+  replyToCommentPHID VARCHAR(64) COLLATE utf8_bin,
+  legacyCommentID INT UNSIGNED,
+  UNIQUE KEY `key_phid` (phid),
+  UNIQUE KEY `key_version` (transactionPHID, commentVersion),
+  KEY `key_path` (pathID),
+  KEY `key_draft` (authorPHID, transactionPHID),
+  KEY `key_commit` (commitPHID),
+  KEY `key_legacy` (legacyCommentID)
+) ENGINE=InnoDB, COLLATE utf8_general_ci;
diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -1148,6 +1148,9 @@
     'PhabricatorAuditPreviewController' => 'applications/audit/controller/PhabricatorAuditPreviewController.php',
     'PhabricatorAuditReplyHandler' => 'applications/audit/mail/PhabricatorAuditReplyHandler.php',
     'PhabricatorAuditStatusConstants' => 'applications/audit/constants/PhabricatorAuditStatusConstants.php',
+    'PhabricatorAuditTransaction' => 'applications/audit/storage/PhabricatorAuditTransaction.php',
+    'PhabricatorAuditTransactionComment' => 'applications/audit/storage/PhabricatorAuditTransactionComment.php',
+    'PhabricatorAuditTransactionQuery' => 'applications/audit/query/PhabricatorAuditTransactionQuery.php',
     'PhabricatorAuthAccountView' => 'applications/auth/view/PhabricatorAuthAccountView.php',
     'PhabricatorAuthApplication' => 'applications/auth/application/PhabricatorAuthApplication.php',
     'PhabricatorAuthAuthFactorPHIDType' => 'applications/auth/phid/PhabricatorAuthAuthFactorPHIDType.php',
@@ -3940,6 +3943,9 @@
     'PhabricatorAuditManagementWorkflow' => 'PhabricatorManagementWorkflow',
     'PhabricatorAuditPreviewController' => 'PhabricatorAuditController',
     'PhabricatorAuditReplyHandler' => 'PhabricatorMailReplyHandler',
+    'PhabricatorAuditTransaction' => 'PhabricatorApplicationTransaction',
+    'PhabricatorAuditTransactionComment' => 'PhabricatorApplicationTransactionComment',
+    'PhabricatorAuditTransactionQuery' => 'PhabricatorApplicationTransactionQuery',
     'PhabricatorAuthAccountView' => 'AphrontView',
     'PhabricatorAuthApplication' => 'PhabricatorApplication',
     'PhabricatorAuthAuthFactorPHIDType' => 'PhabricatorPHIDType',
diff --git a/src/applications/audit/query/PhabricatorAuditTransactionQuery.php b/src/applications/audit/query/PhabricatorAuditTransactionQuery.php
new file mode 100644
--- /dev/null
+++ b/src/applications/audit/query/PhabricatorAuditTransactionQuery.php
@@ -0,0 +1,10 @@
+<?php
+
+final class PhabricatorAuditTransactionQuery
+  extends PhabricatorApplicationTransactionQuery {
+
+  public function getTemplateApplicationTransaction() {
+    return new PhabricatorAuditTransaction();
+  }
+
+}
diff --git a/src/applications/audit/storage/PhabricatorAuditTransaction.php b/src/applications/audit/storage/PhabricatorAuditTransaction.php
new file mode 100644
--- /dev/null
+++ b/src/applications/audit/storage/PhabricatorAuditTransaction.php
@@ -0,0 +1,18 @@
+<?php
+
+final class PhabricatorAuditTransaction
+  extends PhabricatorApplicationTransaction {
+
+  public function getApplicationName() {
+    return 'audit';
+  }
+
+  public function getApplicationTransactionType() {
+    return PhabricatorRepositoryCommitPHIDType::TYPECONST;
+  }
+
+  public function getApplicationTransactionCommentObject() {
+    return new PhabricatorAuditTransactionComment();
+  }
+
+}
diff --git a/src/applications/audit/storage/PhabricatorAuditTransactionComment.php b/src/applications/audit/storage/PhabricatorAuditTransactionComment.php
new file mode 100644
--- /dev/null
+++ b/src/applications/audit/storage/PhabricatorAuditTransactionComment.php
@@ -0,0 +1,25 @@
+<?php
+
+final class PhabricatorAuditTransactionComment
+  extends PhabricatorApplicationTransactionComment {
+
+  protected $commitPHID;
+  protected $pathID;
+  protected $isNewFile = 0;
+  protected $lineNumber = 0;
+  protected $lineLength = 0;
+  protected $fixedState;
+  protected $hasReplies = 0;
+  protected $replyToCommentPHID;
+  protected $legacyCommentID;
+
+  public function getApplicationTransactionObject() {
+    return new PhabricatorAuditTransaction();
+  }
+
+  public function shouldUseMarkupCache($field) {
+    // Only cache submitted comments.
+    return ($this->getTransactionPHID() != null);
+  }
+
+}