diff --git a/scripts/test/http.php b/scripts/test/http.php
--- a/scripts/test/http.php
+++ b/scripts/test/http.php
@@ -22,7 +22,7 @@
 $uri = $args->getArg('url');
 if (count($uri) !== 1) {
   throw new PhutilArgumentUsageException(
-    "Specify exactly one URL to retrieve.");
+    'Specify exactly one URL to retrieve.');
 }
 $uri = head($uri);
 
diff --git a/scripts/test/progress_bar.php b/scripts/test/progress_bar.php
--- a/scripts/test/progress_bar.php
+++ b/scripts/test/progress_bar.php
@@ -46,7 +46,7 @@
     ->setTotal(100);
   for ($ii = 0; $ii < 100; $ii++) {
     if ($ii == 20) {
-      throw new Exception("Boo!");
+      throw new Exception('Boo!');
     }
     $bar->update(1);
     usleep(10000);
diff --git a/scripts/utils/lock.php b/scripts/utils/lock.php
--- a/scripts/utils/lock.php
+++ b/scripts/utils/lock.php
@@ -65,7 +65,7 @@
   }
 }
 
-while (!$console->confirm("Release lock?")) {
+while (!$console->confirm('Release lock?')) {
   // Keep asking until they say yes.
 }
 
diff --git a/scripts/utils/utf8.php b/scripts/utils/utf8.php
--- a/scripts/utils/utf8.php
+++ b/scripts/utils/utf8.php
@@ -94,9 +94,9 @@
     $data = read($file);
     $ok = phutil_is_utf8($data);
     if ($ok) {
-      echo "OKAY";
+      echo 'OKAY';
     } else {
-      echo "FAIL";
+      echo 'FAIL';
     }
     echo "  ".name($file)."\n";
 
@@ -158,7 +158,7 @@
       $out .= $match[1];
       $line = substr($line, strlen($match[1]));
     } else {
-      $chr = sprintf("<0x%0X>", ord($line[0]));
+      $chr = sprintf('<0x%0X>', ord($line[0]));
       $chr = phutil_console_format('##%s##', $chr);
       $out .= $chr;
       $line = substr($line, 1);
diff --git a/src/__phutil_library_init__.php b/src/__phutil_library_init__.php
--- a/src/__phutil_library_init__.php
+++ b/src/__phutil_library_init__.php
@@ -145,7 +145,7 @@
       switch ($version) {
         case 1:
           throw new Exception(
-            "libphutil v1 libraries are no longer supported.");
+            'libphutil v1 libraries are no longer supported.');
         case 2:
           // NOTE: In version 2 of the library format, all parents (both
           // classes and interfaces) are stored in the 'xmap'. The value is
diff --git a/src/aphront/storage/connection/AphrontDatabaseConnection.php b/src/aphront/storage/connection/AphrontDatabaseConnection.php
--- a/src/aphront/storage/connection/AphrontDatabaseConnection.php
+++ b/src/aphront/storage/connection/AphrontDatabaseConnection.php
@@ -38,11 +38,11 @@
   }
 
   public function asyncQuery($raw_query) {
-    throw new Exception("Async queries are not supported.");
+    throw new Exception('Async queries are not supported.');
   }
 
   public static function resolveAsyncQueries(array $conns, array $asyncs) {
-    throw new Exception("Async queries are not supported.");
+    throw new Exception('Async queries are not supported.');
   }
 
 
diff --git a/src/aphront/storage/connection/AphrontDatabaseTransactionState.php b/src/aphront/storage/connection/AphrontDatabaseTransactionState.php
--- a/src/aphront/storage/connection/AphrontDatabaseTransactionState.php
+++ b/src/aphront/storage/connection/AphrontDatabaseTransactionState.php
@@ -39,7 +39,7 @@
 
   public function endReadLocking() {
     if ($this->readLockLevel == 0) {
-      throw new Exception("Too many calls to endReadLocking()!");
+      throw new Exception('Too many calls to endReadLocking()!');
     }
     $this->readLockLevel--;
     return $this;
@@ -56,7 +56,7 @@
 
   public function endWriteLocking() {
     if ($this->writeLockLevel == 0) {
-      throw new Exception("Too many calls to endWriteLocking()!");
+      throw new Exception('Too many calls to endWriteLocking()!');
     }
     $this->writeLockLevel--;
     return $this;
diff --git a/src/aphront/storage/connection/mysql/AphrontMySQLDatabaseConnection.php b/src/aphront/storage/connection/mysql/AphrontMySQLDatabaseConnection.php
--- a/src/aphront/storage/connection/mysql/AphrontMySQLDatabaseConnection.php
+++ b/src/aphront/storage/connection/mysql/AphrontMySQLDatabaseConnection.php
@@ -34,8 +34,8 @@
       // installed, which has bitten me on three separate occasions. Make sure
       // such failures are explicit and loud.
       throw new Exception(
-        "About to call mysql_connect(), but the PHP MySQL extension is not ".
-        "available!");
+        'About to call mysql_connect(), but the PHP MySQL extension is not '.
+        'available!');
     }
 
     $user = $this->getConfiguration('user');
@@ -117,7 +117,7 @@
     }
 
     if (!$processed_all) {
-      throw new Exception("There are some results left in the result set.");
+      throw new Exception('There are some results left in the result set.');
     }
 
     return $results;
diff --git a/src/aphront/storage/connection/mysql/AphrontMySQLiDatabaseConnection.php b/src/aphront/storage/connection/mysql/AphrontMySQLiDatabaseConnection.php
--- a/src/aphront/storage/connection/mysql/AphrontMySQLiDatabaseConnection.php
+++ b/src/aphront/storage/connection/mysql/AphrontMySQLiDatabaseConnection.php
@@ -32,8 +32,8 @@
   protected function connect() {
     if (!class_exists('mysqli', false)) {
       throw new Exception(
-        "About to call new mysqli(), but the PHP MySQLi extension is not ".
-        "available!");
+        'About to call new mysqli(), but the PHP MySQLi extension is not '.
+        'available!');
     }
 
     $user = $this->getConfiguration('user');
@@ -103,7 +103,7 @@
     }
 
     if ($conn->more_results()) {
-      throw new Exception("There are some results left in the result set.");
+      throw new Exception('There are some results left in the result set.');
     }
 
     return $results;
diff --git a/src/aphront/storage/exception/AphrontQueryParameterException.php b/src/aphront/storage/exception/AphrontQueryParameterException.php
--- a/src/aphront/storage/exception/AphrontQueryParameterException.php
+++ b/src/aphront/storage/exception/AphrontQueryParameterException.php
@@ -8,7 +8,7 @@
   private $query;
 
   public function __construct($query, $message) {
-    parent::__construct($message." Query: ".$query);
+    parent::__construct($message.' Query: '.$query);
     $this->query = $query;
   }
 
diff --git a/src/aphront/writeguard/AphrontWriteGuard.php b/src/aphront/writeguard/AphrontWriteGuard.php
--- a/src/aphront/writeguard/AphrontWriteGuard.php
+++ b/src/aphront/writeguard/AphrontWriteGuard.php
@@ -67,14 +67,14 @@
   public function __construct($callback) {
     if (self::$instance) {
       throw new Exception(
-        "An AphrontWriteGuard already exists. Dispose of the previous guard ".
-        "before creating a new one.");
+        'An AphrontWriteGuard already exists. Dispose of the previous guard '.
+        'before creating a new one.');
     }
     if (self::$allowUnguardedWrites) {
       throw new Exception(
-        "An AphrontWriteGuard is being created in a context which permits ".
-        "unguarded writes unconditionally. This is not allowed and indicates ".
-        "a serious error.");
+        'An AphrontWriteGuard is being created in a context which permits '.
+        'unguarded writes unconditionally. This is not allowed and indicates '.
+        'a serious error.');
     }
     if (!self::$abruptExitlistenerIsInstalled) {
       self::$abruptExitlistenerIsInstalled = true;
@@ -96,13 +96,13 @@
   public function dispose() {
     if (!self::$instance) {
       throw new Exception(
-        "Attempting to dispose of write guard, but no write guard is active!");
+        'Attempting to dispose of write guard, but no write guard is active!');
     }
 
     if ($this->allowDepth > 0) {
       throw new Exception(
-        "Imbalanced AphrontWriteGuard: more beginUnguardedWrites() calls than ".
-        "endUnguardedWrites() calls.");
+        'Imbalanced AphrontWriteGuard: more beginUnguardedWrites() calls than '.
+        'endUnguardedWrites() calls.');
     }
     self::$instance = null;
   }
@@ -164,8 +164,8 @@
     if (!self::$instance) {
       if (!self::$allowUnguardedWrites) {
         throw new Exception(
-          "Unguarded write! There must be an active AphrontWriteGuard to ".
-          "perform writes.");
+          'Unguarded write! There must be an active AphrontWriteGuard to '.
+          'perform writes.');
       } else {
         // Unguarded writes are being allowed unconditionally.
         return;
@@ -239,8 +239,8 @@
     }
     if (self::$instance->allowDepth <= 0) {
       throw new Exception(
-        "Imbalanced AphrontWriteGuard: more endUnguardedWrites() calls than ".
-        "beginUnguardedWrites() calls.");
+        'Imbalanced AphrontWriteGuard: more endUnguardedWrites() calls than '.
+        'beginUnguardedWrites() calls.');
     }
     self::$instance->allowDepth--;
   }
@@ -261,9 +261,9 @@
   public static function allowDangerousUnguardedWrites($allow) {
     if (self::$instance) {
       throw new Exception(
-        "You can not unconditionally disable AphrontWriteGuard by calling ".
-        "allowDangerousUnguardedWrites() while a write guard is active. Use ".
-        "beginUnguardedWrites() to temporarily allow unguarded writes.");
+        'You can not unconditionally disable AphrontWriteGuard by calling '.
+        'allowDangerousUnguardedWrites() while a write guard is active. Use '.
+        'beginUnguardedWrites() to temporarily allow unguarded writes.');
     }
     self::$allowUnguardedWrites = true;
   }
@@ -280,9 +280,9 @@
   public function __destruct() {
     if (isset(self::$instance)) {
       throw new Exception(
-        "AphrontWriteGuard was not properly disposed of! Call dispose() on ".
-        "every AphrontWriteGuard object you instantiate or use phutil_exit() ".
-        "to exit abruptly while debugging.");
+        'AphrontWriteGuard was not properly disposed of! Call dispose() on '.
+        'every AphrontWriteGuard object you instantiate or use phutil_exit() '.
+        'to exit abruptly while debugging.');
     }
   }
 }
diff --git a/src/auth/PhutilAuthAdapterLDAP.php b/src/auth/PhutilAuthAdapterLDAP.php
--- a/src/auth/PhutilAuthAdapterLDAP.php
+++ b/src/auth/PhutilAuthAdapterLDAP.php
@@ -354,7 +354,7 @@
         if (!$ok) {
           $this->raiseConnectionException(
             $conn,
-            pht("Unable to start TLS connection when connecting to LDAP."));
+            pht('Unable to start TLS connection when connecting to LDAP.'));
         }
       }
 
@@ -412,7 +412,7 @@
     if (!$result) {
       $this->raiseConnectionException(
         $conn,
-        pht("LDAP search failed."));
+        pht('LDAP search failed.'));
     }
 
     $entries = @ldap_get_entries($conn, $result);
@@ -420,7 +420,7 @@
     if (!$entries) {
       $this->raiseConnectionException(
         $conn,
-        pht("Failed to get LDAP entries from search result."));
+        pht('Failed to get LDAP entries from search result.'));
     }
 
     $results = array();
@@ -448,7 +448,7 @@
         $error);
     } else {
       $full_message = pht(
-        "LDAP Exception: %s",
+        'LDAP Exception: %s',
         $message);
     }
 
diff --git a/src/auth/PhutilAuthAdapterOAuth.php b/src/auth/PhutilAuthAdapterOAuth.php
--- a/src/auth/PhutilAuthAdapterOAuth.php
+++ b/src/auth/PhutilAuthAdapterOAuth.php
@@ -152,7 +152,7 @@
     $code = $this->getCode();
     if (!$code) {
       throw new Exception(
-        "Call setCode() before accessing adapter information.");
+        'Call setCode() before accessing adapter information.');
     }
 
     $params = array(
@@ -192,7 +192,7 @@
     }
 
     if (isset($data['error'])) {
-      throw new Exception("Access token error: ".$data['error']);
+      throw new Exception('Access token error: '.$data['error']);
     }
 
     return $data;
diff --git a/src/auth/PhutilAuthAdapterOAuth1.php b/src/auth/PhutilAuthAdapterOAuth1.php
--- a/src/auth/PhutilAuthAdapterOAuth1.php
+++ b/src/auth/PhutilAuthAdapterOAuth1.php
@@ -101,7 +101,7 @@
     if (strlen($consumer_key)) {
       $future->setConsumerKey($consumer_key);
     } else {
-      throw new Exception("setConsumerKey() is required!");
+      throw new Exception('setConsumerKey() is required!');
     }
 
     $consumer_secret = $this->getConsumerSecret();
@@ -137,7 +137,7 @@
 
     // NOTE: Per the spec, this value MUST be the string 'true'.
     $confirmed = idx($data, 'oauth_callback_confirmed');
-    if ($confirmed !== "true") {
+    if ($confirmed !== 'true') {
       throw new Exception(
         "Expected 'oauth_callback_confirmed' to be 'true'!");
     }
@@ -154,10 +154,10 @@
     $this->willFinishOAuthHandshake();
 
     if (!$this->getToken()) {
-      throw new Exception("Expected token to finish OAuth handshake!");
+      throw new Exception('Expected token to finish OAuth handshake!');
     }
     if (!$this->getVerifier()) {
-      throw new Exception("Expected verifier to finish OAuth handshake!");
+      throw new Exception('Expected verifier to finish OAuth handshake!');
     }
 
     $validate_uri = $this->getValidateTokenURI();
diff --git a/src/auth/PhutilAuthAdapterOAuthAmazon.php b/src/auth/PhutilAuthAdapterOAuthAmazon.php
--- a/src/auth/PhutilAuthAdapterOAuthAmazon.php
+++ b/src/auth/PhutilAuthAdapterOAuthAmazon.php
@@ -71,8 +71,8 @@
     $data = json_decode($body, true);
     if (!is_array($data)) {
       throw new Exception(
-        "Expected valid JSON response from Amazon account data request, ".
-        "got: ".$body);
+        'Expected valid JSON response from Amazon account data request, '.
+        'got: '.$body);
     }
 
     return $data;
diff --git a/src/auth/PhutilAuthAdapterOAuthDisqus.php b/src/auth/PhutilAuthAdapterOAuthDisqus.php
--- a/src/auth/PhutilAuthAdapterOAuthDisqus.php
+++ b/src/auth/PhutilAuthAdapterOAuthDisqus.php
@@ -74,8 +74,8 @@
     $data = json_decode($body, true);
     if (!is_array($data)) {
       throw new Exception(
-        "Expected valid JSON response from Disqus account data request, ".
-        "got: ".$body);
+        'Expected valid JSON response from Disqus account data request, '.
+        'got: '.$body);
     }
 
     return $data['response'];
diff --git a/src/auth/PhutilAuthAdapterOAuthFacebook.php b/src/auth/PhutilAuthAdapterOAuthFacebook.php
--- a/src/auth/PhutilAuthAdapterOAuthFacebook.php
+++ b/src/auth/PhutilAuthAdapterOAuthFacebook.php
@@ -91,17 +91,17 @@
     $data = json_decode($body, true);
     if (!is_array($data)) {
       throw new Exception(
-        "Expected valid JSON response from Facebook account data request, ".
-        "got: ".$body);
+        'Expected valid JSON response from Facebook account data request, '.
+        'got: '.$body);
     }
 
     if ($this->requireSecureBrowsing) {
       if (empty($data['security_settings']['secure_browsing']['enabled'])) {
         throw new Exception(
           pht(
-            "This Phabricator install requires you to enable Secure Browsing ".
-            "on your Facebook account in order to use it to log in to ".
-            "Phabricator. For more information, see %s",
+            'This Phabricator install requires you to enable Secure Browsing '.
+            'on your Facebook account in order to use it to log in to '.
+            'Phabricator. For more information, see %s',
             'https://www.facebook.com/help/156201551113407/'));
       }
     }
diff --git a/src/auth/PhutilAuthAdapterOAuthGitHub.php b/src/auth/PhutilAuthAdapterOAuthGitHub.php
--- a/src/auth/PhutilAuthAdapterOAuthGitHub.php
+++ b/src/auth/PhutilAuthAdapterOAuthGitHub.php
@@ -63,8 +63,8 @@
     $data = json_decode($body, true);
     if (!is_array($data)) {
       throw new Exception(
-        "Expected valid JSON response from GitHub account data request, ".
-        "got: ".$body);
+        'Expected valid JSON response from GitHub account data request, '.
+        'got: '.$body);
     }
 
     return $data;
diff --git a/src/auth/PhutilAuthAdapterOAuthGoogle.php b/src/auth/PhutilAuthAdapterOAuthGoogle.php
--- a/src/auth/PhutilAuthAdapterOAuthGoogle.php
+++ b/src/auth/PhutilAuthAdapterOAuthGoogle.php
@@ -108,8 +108,8 @@
     $data = json_decode($body, true);
     if (!is_array($data)) {
       throw new Exception(
-        "Expected valid JSON response from Google account data request, ".
-        "got: ".$body);
+        'Expected valid JSON response from Google account data request, '.
+        'got: '.$body);
     }
 
     return $data;
diff --git a/src/auth/PhutilAuthAdapterOAuthJIRA.php b/src/auth/PhutilAuthAdapterOAuthJIRA.php
--- a/src/auth/PhutilAuthAdapterOAuthJIRA.php
+++ b/src/auth/PhutilAuthAdapterOAuthJIRA.php
@@ -135,7 +135,7 @@
    * well known `oauth_verifier` value ("denied"), which we check for here.
    */
   protected function willFinishOAuthHandshake() {
-    $jira_magic_word = "denied";
+    $jira_magic_word = 'denied';
     if ($this->getVerifier() == $jira_magic_word) {
       throw new PhutilAuthUserAbortedException();
     }
diff --git a/src/cache/PhutilKeyValueCacheDirectory.php b/src/cache/PhutilKeyValueCacheDirectory.php
--- a/src/cache/PhutilKeyValueCacheDirectory.php
+++ b/src/cache/PhutilKeyValueCacheDirectory.php
@@ -171,7 +171,7 @@
   private function getCacheDirectory() {
     if (!$this->cacheDirectory) {
       throw new Exception(
-        "Call setCacheDirectory() before using a directory cache!");
+        'Call setCacheDirectory() before using a directory cache!');
     }
     return $this->cacheDirectory;
   }
diff --git a/src/cache/PhutilKeyValueCacheMemcache.php b/src/cache/PhutilKeyValueCacheMemcache.php
--- a/src/cache/PhutilKeyValueCacheMemcache.php
+++ b/src/cache/PhutilKeyValueCacheMemcache.php
@@ -115,7 +115,7 @@
     $n = count($this->servers);
 
     if (!$n) {
-      throw new Exception("Call setServers() before using Memcache!");
+      throw new Exception('Call setServers() before using Memcache!');
     }
 
     foreach ($keys as $key) {
diff --git a/src/cache/PhutilKeyValueCacheOnDisk.php b/src/cache/PhutilKeyValueCacheOnDisk.php
--- a/src/cache/PhutilKeyValueCacheOnDisk.php
+++ b/src/cache/PhutilKeyValueCacheOnDisk.php
@@ -196,7 +196,7 @@
    */
   private function getCacheFile() {
     if (!$this->cacheFile) {
-      throw new Exception("Call setCacheFile() before using a disk cache!");
+      throw new Exception('Call setCacheFile() before using a disk cache!');
     }
     return $this->cacheFile;
   }
diff --git a/src/cache/__tests__/PhutilKeyValueCacheTestCase.php b/src/cache/__tests__/PhutilKeyValueCacheTestCase.php
--- a/src/cache/__tests__/PhutilKeyValueCacheTestCase.php
+++ b/src/cache/__tests__/PhutilKeyValueCacheTestCase.php
@@ -49,7 +49,7 @@
   public function testAPCCache() {
     $cache = new PhutilKeyValueCacheAPC();
     if (!$cache->isAvailable()) {
-      $this->assertSkipped("Cache not available.");
+      $this->assertSkipped('Cache not available.');
     }
     $this->doCacheTest($cache);
   }
diff --git a/src/channel/PhutilChannel.php b/src/channel/PhutilChannel.php
--- a/src/channel/PhutilChannel.php
+++ b/src/channel/PhutilChannel.php
@@ -74,7 +74,7 @@
    */
   public function write($bytes) {
     if (!is_scalar($bytes)) {
-      throw new Exception("PhutilChannel->write() may only write strings!");
+      throw new Exception('PhutilChannel->write() may only write strings!');
     }
 
     $this->obuf->append($bytes);
@@ -416,7 +416,7 @@
     while (!$this->isWriteBufferEmpty()) {
       self::waitForAny(array($this));
       if (!$this->update()) {
-        throw new Exception("Channel closed while flushing output!");
+        throw new Exception('Channel closed while flushing output!');
       }
     }
     return $this;
diff --git a/src/channel/PhutilChannelChannel.php b/src/channel/PhutilChannelChannel.php
--- a/src/channel/PhutilChannelChannel.php
+++ b/src/channel/PhutilChannelChannel.php
@@ -102,8 +102,8 @@
     // protected.
 
     throw new Exception(
-      "Do not call readBytes() or writeBytes() directly on a ".
-      "PhutilChannelChannel. Instead, call read() or write().");
+      'Do not call readBytes() or writeBytes() directly on a '.
+      'PhutilChannelChannel. Instead, call read() or write().');
   }
 
 }
diff --git a/src/channel/PhutilExecChannel.php b/src/channel/PhutilExecChannel.php
--- a/src/channel/PhutilExecChannel.php
+++ b/src/channel/PhutilExecChannel.php
@@ -115,7 +115,7 @@
   }
 
   protected function writeBytes($bytes) {
-    throw new Exception("ExecFuture can not write bytes directly!");
+    throw new Exception('ExecFuture can not write bytes directly!');
   }
 
   protected function getReadSockets() {
diff --git a/src/channel/PhutilProtocolChannel.php b/src/channel/PhutilProtocolChannel.php
--- a/src/channel/PhutilProtocolChannel.php
+++ b/src/channel/PhutilProtocolChannel.php
@@ -135,7 +135,7 @@
       self::waitForAny(array($this));
     }
 
-    throw new Exception("Channel closed while waiting for message!");
+    throw new Exception('Channel closed while waiting for message!');
   }
 
 }
diff --git a/src/channel/PhutilSocketChannel.php b/src/channel/PhutilSocketChannel.php
--- a/src/channel/PhutilSocketChannel.php
+++ b/src/channel/PhutilSocketChannel.php
@@ -50,7 +50,7 @@
       }
       $ok = stream_set_blocking($socket, false);
       if (!$ok) {
-        throw new Exception("Failed to set socket nonblocking!");
+        throw new Exception('Failed to set socket nonblocking!');
       }
     }
 
@@ -82,7 +82,7 @@
     $domain = phutil_is_windows() ? STREAM_PF_INET : STREAM_PF_UNIX;
     $pair = stream_socket_pair($domain, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP);
     if (!$pair) {
-      throw new Exception("stream_socket_pair() failed!");
+      throw new Exception('stream_socket_pair() failed!');
     }
 
     $x = new PhutilSocketChannel($pair[0]);
diff --git a/src/channel/__tests__/PhutilJSONProtocolChannelTestCase.php b/src/channel/__tests__/PhutilJSONProtocolChannelTestCase.php
--- a/src/channel/__tests__/PhutilJSONProtocolChannelTestCase.php
+++ b/src/channel/__tests__/PhutilJSONProtocolChannelTestCase.php
@@ -20,7 +20,7 @@
     $this->assertEqual(
       $dict,
       $result,
-      "Values are identical.");
+      'Values are identical.');
   }
 
 }
diff --git a/src/channel/__tests__/PhutilPHPObjectProtocolChannelTestCase.php b/src/channel/__tests__/PhutilPHPObjectProtocolChannelTestCase.php
--- a/src/channel/__tests__/PhutilPHPObjectProtocolChannelTestCase.php
+++ b/src/channel/__tests__/PhutilPHPObjectProtocolChannelTestCase.php
@@ -17,11 +17,11 @@
 
     $this->assertTrue(
       (array)$object === (array)$result,
-      "Values are identical.");
+      'Values are identical.');
 
     $this->assertFalse(
       $object === $result,
-      "Objects are not the same.");
+      'Objects are not the same.');
   }
 
   public function testCloseSocketWriteChannel() {
@@ -51,7 +51,7 @@
     $future->setTimeout(5);
 
     $exec_channel = new PhutilExecChannel($future);
-    $exec_channel->write("quack");
+    $exec_channel->write('quack');
     $exec_channel->closeWriteChannel();
 
     // If `closeWriteChannel()` did what it is supposed to, this will just
diff --git a/src/console/PhutilConsole.php b/src/console/PhutilConsole.php
--- a/src/console/PhutilConsole.php
+++ b/src/console/PhutilConsole.php
@@ -216,7 +216,7 @@
     } else if ($this->messages) {
       $message = array_shift($this->messages);
     } else {
-      throw new Exception("waitForMessage() called with no messages!");
+      throw new Exception('waitForMessage() called with no messages!');
     }
 
     return $message;
diff --git a/src/console/PhutilConsoleFormatter.php b/src/console/PhutilConsoleFormatter.php
--- a/src/console/PhutilConsoleFormatter.php
+++ b/src/console/PhutilConsoleFormatter.php
@@ -25,8 +25,8 @@
 
   public static function getDisableANSI() {
     if (self::$disableANSI === null) {
-      $term = phutil_utf8_strtolower(getenv("TERM"));
-      if (phutil_is_windows() && $term !== "cygwin" && $term !== "ansi") {
+      $term = phutil_utf8_strtolower(getenv('TERM'));
+      if (phutil_is_windows() && $term !== 'cygwin' && $term !== 'ansi') {
         self::$disableANSI = true;
       } else if (function_exists('posix_isatty') && !posix_isatty(STDOUT)) {
         self::$disableANSI = true;
diff --git a/src/console/PhutilConsoleProgressBar.php b/src/console/PhutilConsoleProgressBar.php
--- a/src/console/PhutilConsoleProgressBar.php
+++ b/src/console/PhutilConsoleProgressBar.php
@@ -110,7 +110,7 @@
       sprintf('%.1f', 100 * $percent));
 
     $this->eraseLine();
-    $console->writeErr("%s", $out);
+    $console->writeErr('%s', $out);
   }
 
   public function done($clean_exit = true) {
@@ -118,7 +118,7 @@
     if ($this->drawn) {
       $this->eraseLine();
       if ($clean_exit) {
-        $console->writeErr("%s\n", "Done.");
+        $console->writeErr("%s\n", 'Done.');
       }
     }
     $this->finished = true;
diff --git a/src/console/PhutilConsoleStdinNotInteractiveException.php b/src/console/PhutilConsoleStdinNotInteractiveException.php
--- a/src/console/PhutilConsoleStdinNotInteractiveException.php
+++ b/src/console/PhutilConsoleStdinNotInteractiveException.php
@@ -11,7 +11,7 @@
 final class PhutilConsoleStdinNotInteractiveException extends Exception {
   public function __construct() {
     parent::__construct(
-      "The program is attempting to read user input, but stdin is being piped ".
-      "from some other source (not a TTY).");
+      'The program is attempting to read user input, but stdin is being piped '.
+      'from some other source (not a TTY).');
   }
 }
diff --git a/src/console/PhutilInteractiveEditor.php b/src/console/PhutilInteractiveEditor.php
--- a/src/console/PhutilInteractiveEditor.php
+++ b/src/console/PhutilInteractiveEditor.php
@@ -268,7 +268,7 @@
     }
 
     throw new Exception(
-      "Unable to launch an interactive text editor. Set the EDITOR ".
-      "environment variable to an appropriate editor.");
+      'Unable to launch an interactive text editor. Set the EDITOR '.
+      'environment variable to an appropriate editor.');
   }
 }
diff --git a/src/console/__tests__/PhutilConsoleWrapTestCase.php b/src/console/__tests__/PhutilConsoleWrapTestCase.php
--- a/src/console/__tests__/PhutilConsoleWrapTestCase.php
+++ b/src/console/__tests__/PhutilConsoleWrapTestCase.php
@@ -26,9 +26,9 @@
           "abc abc!"),
       phutil_console_wrap(
         phutil_console_format(
-          "<bg:red>** ERROR **</bg> abc abc abc abc abc abc abc abc abc abc ".
-          "abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc ".
-          "abc abc!")),
+          '<bg:red>** ERROR **</bg> abc abc abc abc abc abc abc abc abc abc '.
+          'abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc '.
+          'abc abc!')),
       'ANSI escape sequences should not contribute toward wrap width.');
   }
 
diff --git a/src/console/format.php b/src/console/format.php
--- a/src/console/format.php
+++ b/src/console/format.php
@@ -148,7 +148,7 @@
       }
     }
 
-    if ($chr == " ") {
+    if ($chr == ' ') {
       $break_pos = count($line);
       $len_after_break = 0;
     }
diff --git a/src/daemon/PhutilDaemonOverseer.php b/src/daemon/PhutilDaemonOverseer.php
--- a/src/daemon/PhutilDaemonOverseer.php
+++ b/src/daemon/PhutilDaemonOverseer.php
@@ -126,7 +126,7 @@
 
     if (self::$instance) {
       throw new Exception(
-        "You may not instantiate more than one Overseer per process.");
+        'You may not instantiate more than one Overseer per process.');
     }
 
     self::$instance = $this;
@@ -141,7 +141,7 @@
 
       $pid = pcntl_fork();
       if ($pid === -1) {
-        throw new Exception("Unable to fork!");
+        throw new Exception('Unable to fork!');
       } else if ($pid) {
         exit(0);
       }
diff --git a/src/error/PhutilErrorHandler.php b/src/error/PhutilErrorHandler.php
--- a/src/error/PhutilErrorHandler.php
+++ b/src/error/PhutilErrorHandler.php
@@ -394,8 +394,8 @@
       static $handling_error;
       if ($handling_error) {
         error_log(
-          "Error handler was reentered, some errors were not passed to the ".
-          "listener.");
+          'Error handler was reentered, some errors were not passed to the '.
+          'listener.');
         return;
       }
       $handling_error = true;
diff --git a/src/error/__tests__/PhutilOpaqueEnvelopeTestCase.php b/src/error/__tests__/PhutilOpaqueEnvelopeTestCase.php
--- a/src/error/__tests__/PhutilOpaqueEnvelopeTestCase.php
+++ b/src/error/__tests__/PhutilOpaqueEnvelopeTestCase.php
@@ -37,7 +37,7 @@
   }
 
   private function throwTrace($v) {
-    throw new Exception("!");
+    throw new Exception('!');
   }
 
   private function getBacktrace($v) {
diff --git a/src/error/phlog.php b/src/error/phlog.php
--- a/src/error/phlog.php
+++ b/src/error/phlog.php
@@ -61,5 +61,5 @@
  * @group error
  */
 function phutil_error_listener_example($event, $value, array $metadata) {
-  throw new Exception("This is just an example function!");
+  throw new Exception('This is just an example function!');
 }
diff --git a/src/filesystem/FileFinder.php b/src/filesystem/FileFinder.php
--- a/src/filesystem/FileFinder.php
+++ b/src/filesystem/FileFinder.php
@@ -138,7 +138,7 @@
     }
     foreach ($found as $filename) {
       // Only exclude files whose names match relative to the root.
-      if ($dir == "") {
+      if ($dir == '') {
         $matches = true;
         foreach ($this->exclude as $exclude_path) {
           if (fnmatch(ltrim($exclude_path, './'), $dir.$filename)) {
@@ -178,16 +178,16 @@
         "with an absolute path.");
     }
 
-    if ($this->forceMode == "shell") {
+    if ($this->forceMode == 'shell') {
       $php_mode = false;
-    } else if ($this->forceMode == "php") {
+    } else if ($this->forceMode == 'php') {
       $php_mode = true;
     } else {
       $php_mode = (phutil_is_windows() || !Filesystem::binaryExists('find'));
     }
 
     if ($php_mode) {
-      $files = $this->getFiles("");
+      $files = $this->getFiles('');
     } else {
       $args = array();
       $command = array();
diff --git a/src/filesystem/Filesystem.php b/src/filesystem/Filesystem.php
--- a/src/filesystem/Filesystem.php
+++ b/src/filesystem/Filesystem.php
@@ -190,14 +190,14 @@
         if ($ok === false) {
           throw new FilesystemException(
             $try_path,
-            pht("Failed to write file data."));
+            pht('Failed to write file data.'));
         }
 
         $ok = fclose($handle);
         if (!$ok) {
           throw new FilesystemException(
             $try_path,
-            pht("Failed to close file handle."));
+            pht('Failed to close file handle.'));
         }
 
         return $try_path;
@@ -265,7 +265,7 @@
   public static function remove($path) {
     if (!strlen($path)) {
       // Avoid removing PWD.
-      throw new Exception("No path provided to remove().");
+      throw new Exception('No path provided to remove().');
     }
 
     $path = self::resolvePath($path);
@@ -347,7 +347,7 @@
     self::assertExists($path);
 
     if (!@chmod($path, $umask)) {
-      $readable_umask = sprintf("%04o", $umask);
+      $readable_umask = sprintf('%04o', $umask);
       throw new FilesystemException(
         $path, "Failed to chmod `{$path}' to `{$readable_umask}'.");
     }
@@ -392,7 +392,7 @@
   public static function readRandomBytes($number_of_bytes) {
     $number_of_bytes = (int)$number_of_bytes;
     if ($number_of_bytes < 1) {
-      throw new Exception(pht("You must generate at least 1 byte of entropy."));
+      throw new Exception(pht('You must generate at least 1 byte of entropy.'));
     }
 
     // Try to use `openssl_random_psuedo_bytes()` if it's available. This source
@@ -671,7 +671,7 @@
       if ($df !== false && $df < 1024 * 1024) {
         throw new FilesystemException(
           $dir,
-          pht("Failed to create a temporary directory: the disk is full."));
+          pht('Failed to create a temporary directory: the disk is full.'));
       }
 
       throw new FilesystemException(
diff --git a/src/filesystem/PhutilDeferredLog.php b/src/filesystem/PhutilDeferredLog.php
--- a/src/filesystem/PhutilDeferredLog.php
+++ b/src/filesystem/PhutilDeferredLog.php
@@ -123,7 +123,7 @@
   public function setFile($file) {
     if ($this->didWrite) {
       throw new Exception(
-        "You can not change the logfile after a write has occurred!");
+        'You can not change the logfile after a write has occurred!');
     }
     $this->file = $file;
     return $this;
diff --git a/src/filesystem/PhutilFileLock.php b/src/filesystem/PhutilFileLock.php
--- a/src/filesystem/PhutilFileLock.php
+++ b/src/filesystem/PhutilFileLock.php
@@ -107,12 +107,12 @@
   protected function doUnlock() {
     $ok = flock($this->handle, LOCK_UN | LOCK_NB);
     if (!$ok) {
-      throw new Exception("Unable to unlock file!");
+      throw new Exception('Unable to unlock file!');
     }
 
     $ok = fclose($this->handle);
     if (!$ok) {
-      throw new Exception("Unable to close file!");
+      throw new Exception('Unable to close file!');
     }
 
     $this->handle = null;
diff --git a/src/filesystem/__tests__/FileFinderTestCase.php b/src/filesystem/__tests__/FileFinderTestCase.php
--- a/src/filesystem/__tests__/FileFinderTestCase.php
+++ b/src/filesystem/__tests__/FileFinderTestCase.php
@@ -8,8 +8,8 @@
   protected function findFiles($root, $checksums, $type, $path, $mode) {
     $finder = new FileFinder($root);
     $finder->setGenerateChecksums($checksums)
-           ->excludePath("./exclude")
-           ->excludePath("subdir.txt")
+           ->excludePath('./exclude')
+           ->excludePath('subdir.txt')
            ->withType($type)
            ->withPath($path)
            ->withSuffix('txt')
@@ -20,7 +20,7 @@
 
   public function testFinderWithChecksums() {
     $root = dirname(__FILE__) . '/data';
-    foreach (array("php", "shell") as $mode) {
+    foreach (array('php', 'shell') as $mode) {
       $files = $this->findFiles($root, true, 'f', '*', $mode);
 
       // Test whether correct files were found.
@@ -52,7 +52,7 @@
 
   public function testFinderWithoutChecksums() {
     $root = dirname(__FILE__) . '/data';
-    foreach (array("php", "shell") as $mode) {
+    foreach (array('php', 'shell') as $mode) {
       $files = $this->findFiles($root, false, 'f', '*', $mode);
 
       // Test whether correct files were found.
@@ -73,7 +73,7 @@
 
   public function testFinderWithDirectories() {
     $root = dirname(__FILE__) . '/data';
-    foreach (array("php", "shell") as $mode) {
+    foreach (array('php', 'shell') as $mode) {
       $files = $this->findFiles($root, true, '', '*', $mode);
 
       // Test whether the correct files were found.
@@ -96,7 +96,7 @@
 
   public function testFinderWithPath() {
     $root = dirname(__FILE__) . '/data';
-    foreach (array("php", "shell") as $mode) {
+    foreach (array('php', 'shell') as $mode) {
       $files = $this->findFiles($root, true, 'f',
           '*/include_dir.txt/subdir.txt/alsoinclude.txt', $mode);
 
diff --git a/src/filesystem/__tests__/PhutilDeferredLogTestCase.php b/src/filesystem/__tests__/PhutilDeferredLogTestCase.php
--- a/src/filesystem/__tests__/PhutilDeferredLogTestCase.php
+++ b/src/filesystem/__tests__/PhutilDeferredLogTestCase.php
@@ -8,12 +8,12 @@
   public function testLogging() {
     $this->checkLog(
       "derp\n",
-      "derp",
+      'derp',
       array());
 
     $this->checkLog(
       "[20 Aug 1984] alincoln\n",
-      "[%T] %u",
+      '[%T] %u',
       array(
         'T' => '20 Aug 1984',
         'u' => 'alincoln',
@@ -21,14 +21,14 @@
 
     $this->checkLog(
       "%%%%%\n",
-      "%%%%%%%%%%",
+      '%%%%%%%%%%',
       array(
         '%' => '%',
       ));
 
     $this->checkLog(
       "\\000\\001\\002\n",
-      "%a%b%c",
+      '%a%b%c',
       array(
         'a' => chr(0),
         'b' => chr(1),
@@ -37,21 +37,21 @@
 
     $this->checkLog(
       "Download: 100%\n",
-      "Download: %C",
+      'Download: %C',
       array(
         'C' => '100%',
       ));
 
     $this->checkLog(
       "- bee -\n",
-      "%a %b %c",
+      '%a %b %c',
       array(
         'b' => 'bee',
       ));
 
     $this->checkLog(
       "\\\\\n",
-      "%b",
+      '%b',
       array(
         'b' => '\\',
       ));
@@ -73,7 +73,7 @@
 
     $this->checkLog(
       "a % xb\n",
-      "%a %% x%b",
+      '%a %% x%b',
       array(
         'a' => 'a',
         'b' => 'b',
@@ -109,7 +109,7 @@
 
     $futures = array();
     for ($ii = 0; $ii < $n_writers; $ii++) {
-      $futures[] = new ExecFuture("%s %d %s", $bin, $n_lines, (string)$tmp);
+      $futures[] = new ExecFuture('%s %d %s', $bin, $n_lines, (string)$tmp);
     }
 
     Futures($futures)->resolveAll();
diff --git a/src/filesystem/__tests__/PhutilFileLockTestCase.php b/src/filesystem/__tests__/PhutilFileLockTestCase.php
--- a/src/filesystem/__tests__/PhutilFileLockTestCase.php
+++ b/src/filesystem/__tests__/PhutilFileLockTestCase.php
@@ -177,7 +177,7 @@
       }
     }
 
-    throw new Exception("Unable to hold lock in external process!");
+    throw new Exception('Unable to hold lock in external process!');
   }
 
   private function buildLockFuture($flags, $file) {
diff --git a/src/filesystem/linesofalarge/LinesOfALarge.php b/src/filesystem/linesofalarge/LinesOfALarge.php
--- a/src/filesystem/linesofalarge/LinesOfALarge.php
+++ b/src/filesystem/linesofalarge/LinesOfALarge.php
@@ -59,7 +59,7 @@
    */
   final public function setDelimiter($character) {
     if (strlen($character) !== 1) {
-      throw new Exception("Delimiter character MUST be one byte in length.");
+      throw new Exception('Delimiter character MUST be one byte in length.');
     }
     $this->delimiter = $character;
     return $this;
diff --git a/src/filesystem/linesofalarge/LinesOfALargeFile.php b/src/filesystem/linesofalarge/LinesOfALargeFile.php
--- a/src/filesystem/linesofalarge/LinesOfALargeFile.php
+++ b/src/filesystem/linesofalarge/LinesOfALargeFile.php
@@ -80,7 +80,7 @@
     if (!$this->handle) {
       throw new FilesystemException(
         $this->fileName,
-        "Failed to open file!");
+        'Failed to open file!');
     }
   }
 
@@ -100,7 +100,7 @@
     if ($more === false) {
       throw new FilesystemException(
         $this->fileName,
-        "Failed to read file!");
+        'Failed to read file!');
     }
     return $more;
   }
diff --git a/src/filesystem/linesofalarge/__tests__/LinesOfALargeExecFutureTestCase.php b/src/filesystem/linesofalarge/__tests__/LinesOfALargeExecFutureTestCase.php
--- a/src/filesystem/linesofalarge/__tests__/LinesOfALargeExecFutureTestCase.php
+++ b/src/filesystem/linesofalarge/__tests__/LinesOfALargeExecFutureTestCase.php
@@ -12,14 +12,14 @@
     $this->writeAndRead(
       "cat\ndog\nbird\n",
       array(
-        "cat",
-        "dog",
-        "bird",
+        'cat',
+        'dog',
+        'bird',
       ));
   }
 
   public function testExecLargeFile() {
-    $line = "The quick brown fox jumps over the lazy dog.";
+    $line = 'The quick brown fox jumps over the lazy dog.';
     $n    = 100;
 
     $this->writeAndRead(
@@ -57,7 +57,7 @@
     $this->assertEqual(
       $read,
       $lines,
-      "Write: ".phutil_utf8_shorten($write, 32));
+      'Write: '.phutil_utf8_shorten($write, 32));
   }
 
 }
diff --git a/src/filesystem/linesofalarge/__tests__/LinesOfALargeFileTestCase.php b/src/filesystem/linesofalarge/__tests__/LinesOfALargeFileTestCase.php
--- a/src/filesystem/linesofalarge/__tests__/LinesOfALargeFileTestCase.php
+++ b/src/filesystem/linesofalarge/__tests__/LinesOfALargeFileTestCase.php
@@ -7,9 +7,9 @@
 
   public function testBasics() {
     $this->writeAndRead(
-      "abcd",
+      'abcd',
       array(
-        "abcd",
+        'abcd',
       ));
   }
 
@@ -17,9 +17,9 @@
     $this->writeAndRead(
       "bat\ncat\ndog\n",
       array(
-        "bat",
-        "cat",
-        "dog",
+        'bat',
+        'cat',
+        'dog',
       ));
   }
 
@@ -27,9 +27,9 @@
     $this->writeAndRead(
       "bat\ncat\ndog",
       array(
-        "bat",
-        "cat",
-        "dog",
+        'bat',
+        'cat',
+        'dog',
       ));
   }
 
@@ -37,9 +37,9 @@
     $this->writeAndRead(
       "bat\1cat\1dog\1",
       array(
-        "bat",
-        "cat",
-        "dog",
+        'bat',
+        'cat',
+        'dog',
       ),
       "\1");
   }
@@ -55,7 +55,7 @@
   }
 
   public function testLargeFile() {
-    $line = "The quick brown fox jumps over the lazy dog.";
+    $line = 'The quick brown fox jumps over the lazy dog.';
     $n    = 100;
 
     $this->writeAndRead(
@@ -83,8 +83,8 @@
   public function testLineFilter() {
     $write = "bat\ncat\ndog\nBat\nCat\nDog\n";
     $read = array(
-      1 => "cat",
-      4 => "Cat",
+      1 => 'cat',
+      4 => 'Cat',
     );
 
     $tmp = new TempFile();
@@ -101,12 +101,12 @@
     $this->assertEqual(
       $read,
       $lines,
-      "Write: ".phutil_utf8_shorten($write, 32));
+      'Write: '.phutil_utf8_shorten($write, 32));
   }
 
   public function allowCatsOnly($line) {
     $line = strtoupper($line);
-    if ($line != "CAT") {
+    if ($line != 'CAT') {
       return null;
     }
     return $line;
@@ -125,7 +125,7 @@
     $this->assertEqual(
       $read,
       $lines,
-      "Write: ".phutil_utf8_shorten($write, 32));
+      'Write: '.phutil_utf8_shorten($write, 32));
   }
 
 }
diff --git a/src/future/FutureProxy.php b/src/future/FutureProxy.php
--- a/src/future/FutureProxy.php
+++ b/src/future/FutureProxy.php
@@ -24,7 +24,7 @@
 
   protected function getProxiedFuture() {
     if (!$this->proxied) {
-      throw new Exception("The proxied future has not been provided yet.");
+      throw new Exception('The proxied future has not been provided yet.');
     }
     return $this->proxied;
   }
diff --git a/src/future/asana/PhutilAsanaFuture.php b/src/future/asana/PhutilAsanaFuture.php
--- a/src/future/asana/PhutilAsanaFuture.php
+++ b/src/future/asana/PhutilAsanaFuture.php
@@ -36,11 +36,11 @@
       $params = $this->params;
 
       if (!$this->action) {
-        throw new Exception("You must setRawAsanaQuery()!");
+        throw new Exception('You must setRawAsanaQuery()!');
       }
 
       if (!$this->accessToken) {
-        throw new Exception("You must setAccessToken()!");
+        throw new Exception('You must setAccessToken()!');
       }
 
       $uri = new PhutilURI('https://app.asana.com/');
diff --git a/src/future/aws/PhutilAWSFuture.php b/src/future/aws/PhutilAWSFuture.php
--- a/src/future/aws/PhutilAWSFuture.php
+++ b/src/future/aws/PhutilAWSFuture.php
@@ -57,11 +57,11 @@
       $params = $this->params;
 
       if (!$this->params) {
-        throw new Exception("You must setRawAWSQuery()!");
+        throw new Exception('You must setRawAWSQuery()!');
       }
 
       if (!$this->getAWSAccessKey()) {
-        throw new Exception("You must setAWSKeys()!");
+        throw new Exception('You must setAWSKeys()!');
       }
 
       $params['AWSAccessKeyId'] = $this->getAWSAccessKey();
diff --git a/src/future/exec/CommandException.php b/src/future/exec/CommandException.php
--- a/src/future/exec/CommandException.php
+++ b/src/future/exec/CommandException.php
@@ -20,15 +20,15 @@
     $summary = array();
     $summary[] = $this->summarize($message);
 
-    $summary[] = "COMMAND";
+    $summary[] = 'COMMAND';
     $summary[] = $this->summarize($command);
 
     $summary[] = null;
-    $summary[] = "STDOUT";
+    $summary[] = 'STDOUT';
     $summary[] = $this->summarize($stdout);
 
     $summary[] = null;
-    $summary[] = "STDERR";
+    $summary[] = 'STDERR';
     $summary[] = $this->summarize($stderr);
 
     $summary = implode("\n", $summary);
@@ -62,7 +62,7 @@
     $len = strlen($string);
     if ($len > $limit) {
       $cut = $len - $limit;
-      $suffix = "... (".number_format($cut)." more bytes) ...";
+      $suffix = '... ('.number_format($cut).' more bytes) ...';
       if ($cut > strlen($suffix)) {
         $string = substr($string, 0, $limit).$suffix;
       }
diff --git a/src/future/http/BaseHTTPFuture.php b/src/future/http/BaseHTTPFuture.php
--- a/src/future/http/BaseHTTPFuture.php
+++ b/src/future/http/BaseHTTPFuture.php
@@ -156,7 +156,7 @@
    */
   public function setData($data) {
     if (!is_string($data) && !is_array($data)) {
-      throw new Exception("Data parameter must be an array or string.");
+      throw new Exception('Data parameter must be an array or string.');
     }
     $this->data = $data;
     return $this;
diff --git a/src/future/http/HTTPFuture.php b/src/future/http/HTTPFuture.php
--- a/src/future/http/HTTPFuture.php
+++ b/src/future/http/HTTPFuture.php
@@ -66,7 +66,7 @@
 
     if (isset($parts['user']) || isset($parts['pass'])) {
       throw new Exception(
-        "HTTP Basic Auth is not supported by HTTPFuture.");
+        'HTTP Basic Auth is not supported by HTTPFuture.');
     }
 
     if (isset($parts['path'])) {
@@ -145,7 +145,7 @@
       if (strlen($this->writeBuffer)) {
         $bytes = @fwrite($this->socket, $this->writeBuffer);
         if ($bytes === false) {
-          throw new Exception("Failed to write to buffer.");
+          throw new Exception('Failed to write to buffer.');
         } else if ($bytes) {
           $this->writeBuffer = substr($this->writeBuffer, $bytes);
         }
@@ -160,7 +160,7 @@
       }
 
       if ($data === false) {
-        throw new Exception("Failed to read socket.");
+        throw new Exception('Failed to read socket.');
       }
     }
 
@@ -187,7 +187,7 @@
 
     $ok = stream_set_blocking($socket, 0);
     if (!$ok) {
-      throw new Exception("Failed to set stream nonblocking.");
+      throw new Exception('Failed to set stream nonblocking.');
     }
 
     $this->writeBuffer = $this->buildHTTPRequest();
diff --git a/src/future/http/status/HTTPFutureResponseStatusParse.php b/src/future/http/status/HTTPFutureResponseStatusParse.php
--- a/src/future/http/status/HTTPFutureResponseStatusParse.php
+++ b/src/future/http/status/HTTPFutureResponseStatusParse.php
@@ -26,7 +26,7 @@
 
   protected function getErrorCodeDescription($code) {
     return
-      "The remote host returned something other than an HTTP response: ".
+      'The remote host returned something other than an HTTP response: '.
       $this->rawResponse;
   }
 
diff --git a/src/future/oauth/PhutilOAuth1Future.php b/src/future/oauth/PhutilOAuth1Future.php
--- a/src/future/oauth/PhutilOAuth1Future.php
+++ b/src/future/oauth/PhutilOAuth1Future.php
@@ -126,7 +126,7 @@
       foreach ($oauth_headers as $header => $value) {
         $full_oauth_header[] = $header.'="'.urlencode($value).'"';
       }
-      $full_oauth_header = 'OAuth '.implode(", ", $full_oauth_header);
+      $full_oauth_header = 'OAuth '.implode(', ', $full_oauth_header);
 
       $future->addHeader('Authorization', $full_oauth_header);
 
diff --git a/src/future/paypal/PhutilPayPalAPIFuture.php b/src/future/paypal/PhutilPayPalAPIFuture.php
--- a/src/future/paypal/PhutilPayPalAPIFuture.php
+++ b/src/future/paypal/PhutilPayPalAPIFuture.php
@@ -51,11 +51,11 @@
       $params = $this->params;
 
       if (!$this->params) {
-        throw new Exception("You must setRawPayPalQuery()!");
+        throw new Exception('You must setRawPayPalQuery()!');
       }
 
       if (!$this->apiUsername) {
-        throw new Exception("You must set PayPal API credentials!");
+        throw new Exception('You must set PayPal API credentials!');
       }
 
       $params['VERSION'] = '98.0';
@@ -82,7 +82,7 @@
 
     if (idx($dict, 'ACK') !== 'Success') {
       throw new Exception(
-        "PayPal API call failed: ".print_r($dict, true));
+        'PayPal API call failed: '.print_r($dict, true));
     }
 
     return $dict;
diff --git a/src/future/twitch/PhutilTwitchFuture.php b/src/future/twitch/PhutilTwitchFuture.php
--- a/src/future/twitch/PhutilTwitchFuture.php
+++ b/src/future/twitch/PhutilTwitchFuture.php
@@ -42,11 +42,11 @@
       $params = $this->params;
 
       if (!$this->action) {
-        throw new Exception("You must setRawTwitchQuery()!");
+        throw new Exception('You must setRawTwitchQuery()!');
       }
 
       if (!$this->accessToken) {
-        throw new Exception("You must setAccessToken()!");
+        throw new Exception('You must setAccessToken()!');
       }
 
       $uri = new PhutilURI('https://api.twitch.tv/');
diff --git a/src/future/wordpress/PhutilWordPressFuture.php b/src/future/wordpress/PhutilWordPressFuture.php
--- a/src/future/wordpress/PhutilWordPressFuture.php
+++ b/src/future/wordpress/PhutilWordPressFuture.php
@@ -39,11 +39,11 @@
       $params = $this->params;
 
       if (!$this->action) {
-        throw new Exception("You must setRawWordPressQuery()!");
+        throw new Exception('You must setRawWordPressQuery()!');
       }
 
       if (!$this->accessToken) {
-        throw new Exception("You must setAccessToken()!");
+        throw new Exception('You must setAccessToken()!');
       }
 
       $uri = new PhutilURI('https://public-api.wordpress.com/');
diff --git a/src/grammar/PhutilContextFreeGrammar.php b/src/grammar/PhutilContextFreeGrammar.php
--- a/src/grammar/PhutilContextFreeGrammar.php
+++ b/src/grammar/PhutilContextFreeGrammar.php
@@ -9,7 +9,7 @@
 
   abstract protected function getRules();
 
-  public function generateSeveral($count, $implode = " ") {
+  public function generateSeveral($count, $implode = ' ') {
     $paragraph = array();
     for ($ii = 0; $ii < $count; $ii++) {
       $paragraph[$ii] = $this->generate();
@@ -25,7 +25,7 @@
 
   final protected function applyRules($input, &$count, array $rules) {
     if (++$count > $this->limit) {
-      throw new Exception("Token replacement count exceeded limit!");
+      throw new Exception('Token replacement count exceeded limit!');
     }
 
     $matches = null;
@@ -84,10 +84,10 @@
   private static function strPadLines($text, $num_spaces = 2) {
     $text_lines = phutil_split_lines($text);
     foreach ($text_lines as $linenr => $line) {
-      $text_lines[$linenr] = str_repeat(" ", $num_spaces) . $line;
+      $text_lines[$linenr] = str_repeat(' ', $num_spaces) . $line;
     }
 
-    return implode("", $text_lines);
+    return implode('', $text_lines);
   }
 
 }
diff --git a/src/grammar/code/PhutilCLikeCodeSnippetContextFreeGrammar.php b/src/grammar/code/PhutilCLikeCodeSnippetContextFreeGrammar.php
--- a/src/grammar/code/PhutilCLikeCodeSnippetContextFreeGrammar.php
+++ b/src/grammar/code/PhutilCLikeCodeSnippetContextFreeGrammar.php
@@ -48,7 +48,7 @@
   protected function getFuncCallGrammarSet() {
     return $this->buildGrammarSet('funccall',
       array(
-        "[funcname]([funccallparam])",
+        '[funcname]([funccallparam])',
       ));
   }
 
@@ -101,8 +101,8 @@
   protected function getClassDeclGrammarSet() {
     return $this->buildGrammarSet('classdecl',
       array(
-        "[classinheritancemod] class [classname] {[classbody, indent, block]}",
-        "class [classname] {[classbody, indent, block]}",
+        '[classinheritancemod] class [classname] {[classbody, indent, block]}',
+        'class [classname] {[classbody, indent, block]}',
       ));
   }
 
@@ -132,7 +132,7 @@
   protected function getClassBodyGrammarSet() {
     return $this->buildGrammarSet('classbody',
       array(
-        "[methoddecl]",
+        '[methoddecl]',
         "[methoddecl]\n\n[methoddecl]",
         "[propdecl]\n[propdecl]\n\n[methoddecl]\n\n[methoddecl]",
         "[propdecl]\n[propdecl]\n[propdecl]\n\n[methoddecl]\n\n[methoddecl]".
diff --git a/src/internationalization/__tests__/PhutilTranslatorTestCase.php b/src/internationalization/__tests__/PhutilTranslatorTestCase.php
--- a/src/internationalization/__tests__/PhutilTranslatorTestCase.php
+++ b/src/internationalization/__tests__/PhutilTranslatorTestCase.php
@@ -198,7 +198,7 @@
     $translator = new PhutilTranslator();
     foreach ($tests as $original => $translations) {
       foreach ($translations as $translation => $expect) {
-        $valid = ($expect ? "valid" : "invalid");
+        $valid = ($expect ? 'valid' : 'invalid');
         $this->assertEqual(
           $expect,
           $translator->validateTranslation($original, $translation),
diff --git a/src/lexer/PhutilPHPFragmentLexer.php b/src/lexer/PhutilPHPFragmentLexer.php
--- a/src/lexer/PhutilPHPFragmentLexer.php
+++ b/src/lexer/PhutilPHPFragmentLexer.php
@@ -155,8 +155,8 @@
         array('0[xX][a-fA-F0-9]+', 'mh'),
         array('0[bB][0-1]+', 'm'),
         array('\d+', 'mi'),
-        array("'", "s1", 'string1'),
-        array("`", "sb", 'stringb'),
+        array("'", 's1', 'string1'),
+        array('`', 'sb', 'stringb'),
         array('"', 's2', 'string2'),
         array('.', null),
       )),
diff --git a/src/lexer/PhutilShellLexer.php b/src/lexer/PhutilShellLexer.php
--- a/src/lexer/PhutilShellLexer.php
+++ b/src/lexer/PhutilShellLexer.php
@@ -30,7 +30,7 @@
     $tokens = $this->getTokens($string);
     if (count($this->getLexerState()) > 1) {
       throw new UnexpectedValueException(
-        "Unterminated string in argument list!");
+        'Unterminated string in argument list!');
     }
 
     foreach ($tokens as $key => $token) {
diff --git a/src/markup/__tests__/PhutilSafeHTMLTestCase.php b/src/markup/__tests__/PhutilSafeHTMLTestCase.php
--- a/src/markup/__tests__/PhutilSafeHTMLTestCase.php
+++ b/src/markup/__tests__/PhutilSafeHTMLTestCase.php
@@ -7,7 +7,7 @@
 
   public function testOperator() {
     if (!extension_loaded('operator')) {
-      $this->assertSkipped("Operator extension not available.");
+      $this->assertSkipped('Operator extension not available.');
     }
 
     $a = phutil_tag('a');
diff --git a/src/markup/engine/PhutilRemarkupEngine.php b/src/markup/engine/PhutilRemarkupEngine.php
--- a/src/markup/engine/PhutilRemarkupEngine.php
+++ b/src/markup/engine/PhutilRemarkupEngine.php
@@ -165,9 +165,9 @@
 
           if ($prev_block
             && self::shouldMergeBlocks($text, $prev_block, $curr_block)) {
-            $blocks[last_key($blocks)]["num_lines"] += $curr_block["num_lines"];
-            $blocks[last_key($blocks)]["is_empty"] =
-              $blocks[last_key($blocks)]["is_empty"] && $curr_block["is_empty"];
+            $blocks[last_key($blocks)]['num_lines'] += $curr_block['num_lines'];
+            $blocks[last_key($blocks)]['is_empty'] =
+              $blocks[last_key($blocks)]['is_empty'] && $curr_block['is_empty'];
           } else {
             $blocks[] = $curr_block;
           }
@@ -178,7 +178,7 @@
       }
 
       if ($starting_cursor === $cursor) {
-        throw new Exception("Block in text did not match any block rule.");
+        throw new Exception('Block in text did not match any block rule.');
       }
     }
 
@@ -237,9 +237,9 @@
   }
 
   private static function shouldMergeBlocks($text, $prev_block, $curr_block) {
-    $block_rules = ipull(array($prev_block, $curr_block), "rule");
+    $block_rules = ipull(array($prev_block, $curr_block), 'rule');
 
-    $default_rule = "PhutilRemarkupEngineRemarkupDefaultBlockRule";
+    $default_rule = 'PhutilRemarkupEngineRemarkupDefaultBlockRule';
     try {
       assert_instances_of($block_rules, $default_rule);
 
@@ -254,8 +254,8 @@
       }
 
       // If the current line and the last line have content, keep merging
-      if (strlen(trim($text[$curr_block["start"] - 1]))) {
-        if (strlen(trim($text[$curr_block["start"]]))) {
+      if (strlen(trim($text[$curr_block['start'] - 1]))) {
+        if (strlen(trim($text[$curr_block['start']]))) {
           return true;
         }
       }
diff --git a/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php b/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
--- a/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
+++ b/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
@@ -33,9 +33,9 @@
         // test, "~" is used as a placeholder for "\1" since it's hard to type
         // "\1".
 
-        $input_remarkup = str_replace("~", "\1", $input_remarkup);
-        $expected_output = str_replace("~", "\1", $expected_output);
-        $expected_text = str_replace("~", "\1", $expected_text);
+        $input_remarkup = str_replace('~', "\1", $input_remarkup);
+        $expected_output = str_replace('~', "\1", $expected_output);
+        $expected_text = str_replace('~', "\1", $expected_text);
         break;
       case 'toc.txt':
         $engine->setConfig('header.generate-toc', true);
diff --git a/src/markup/engine/remarkup/PhutilRemarkupBlockStorage.php b/src/markup/engine/remarkup/PhutilRemarkupBlockStorage.php
--- a/src/markup/engine/remarkup/PhutilRemarkupBlockStorage.php
+++ b/src/markup/engine/remarkup/PhutilRemarkupBlockStorage.php
@@ -40,7 +40,7 @@
   private $index;
 
   public function store($text) {
-    $key = self::MAGIC_BYTE.(++$this->index)."Z";
+    $key = self::MAGIC_BYTE.(++$this->index).'Z';
     $this->map[$key] = $text;
     return $key;
   }
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupCodeBlockRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupCodeBlockRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupCodeBlockRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupCodeBlockRule.php
@@ -9,9 +9,9 @@
   public function getMatchingLineCount(array $lines, $cursor) {
     $num_lines = 0;
     $match_ticks = null;
-    if (preg_match("/^(\s{2,}).+/", $lines[$cursor])) {
+    if (preg_match('/^(\s{2,}).+/', $lines[$cursor])) {
       $match_ticks = false;
-    } else if (preg_match("/^(```)/", $lines[$cursor])) {
+    } else if (preg_match('/^(```)/', $lines[$cursor])) {
       $match_ticks = true;
     } else {
       return $num_lines;
@@ -19,7 +19,7 @@
 
     $num_lines++;
 
-    if ($match_ticks && preg_match("/^(```)(.*)(```)\s*$/", $lines[$cursor])) {
+    if ($match_ticks && preg_match('/^(```)(.*)(```)\s*$/', $lines[$cursor])) {
       return $num_lines;
     }
 
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupHorizontalRuleBlockRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupHorizontalRuleBlockRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupHorizontalRuleBlockRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupHorizontalRuleBlockRule.php
@@ -16,7 +16,7 @@
 
   public function getMatchingLineCount(array $lines, $cursor) {
     $num_lines = 0;
-    $pattern = "/^_{3,}$|^\*\s?\*\s?\*(\s|\*)*$|^\-\s?\-\s?\-(\s|\-)*$/";
+    $pattern = '/^_{3,}$|^\*\s?\*\s?\*(\s|\*)*$|^\-\s?\-\s?\-(\s|\-)*$/';
     if (preg_match($pattern, rtrim($lines[$cursor], "\n\r"))) {
       $num_lines++;
       $cursor++;
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupInterpreterRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupInterpreterRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupInterpreterRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupInterpreterRule.php
@@ -55,11 +55,11 @@
 
     $lines[$first_key] = preg_replace(
       self::START_BLOCK_PATTERN,
-      "",
+      '',
       $lines[$first_key]);
     $lines[$last_key] = preg_replace(
       self::END_BLOCK_PATTERN,
-      "",
+      '',
       $lines[$last_key]);
 
     if (trim($lines[$first_key]) === '') {
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupLiteralBlockRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupLiteralBlockRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupLiteralBlockRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupLiteralBlockRule.php
@@ -8,11 +8,11 @@
 
   public function getMatchingLineCount(array $lines, $cursor) {
     $num_lines = 0;
-    if (preg_match("/^%%%/", $lines[$cursor])) {
+    if (preg_match('/^%%%/', $lines[$cursor])) {
       $num_lines++;
 
       while (isset($lines[$cursor])) {
-        if (!preg_match("/%%%\s*$/", $lines[$cursor])) {
+        if (!preg_match('/%%%\s*$/', $lines[$cursor])) {
           $num_lines++;
           $cursor++;
           continue;
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTableBlockRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTableBlockRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTableBlockRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTableBlockRule.php
@@ -50,7 +50,7 @@
     $row_regex = '@'.$row_fragment.'@Usi';
     if (!preg_match_all($row_regex, $body, $matches, PREG_SET_ORDER)) {
       throw new Exception(
-        "Bug in Remarkup tables, parsing fails for input: ".$text);
+        'Bug in Remarkup tables, parsing fails for input: '.$text);
     }
 
     $out_rows = array();
@@ -70,7 +70,7 @@
       $cell_regex = '@'.$cell_fragment.'@Usi';
       if (!preg_match_all($cell_regex, $content, $matches, PREG_SET_ORDER)) {
         throw new Exception(
-          "Bug in Remarkup tables, parsing fails for input: ".$text);
+          'Bug in Remarkup tables, parsing fails for input: '.$text);
       }
 
       $out_cells = array();
diff --git a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTestInterpreterRule.php b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTestInterpreterRule.php
--- a/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTestInterpreterRule.php
+++ b/src/markup/engine/remarkup/blockrule/PhutilRemarkupEngineRemarkupTestInterpreterRule.php
@@ -7,7 +7,7 @@
   extends PhutilRemarkupBlockInterpreter {
 
   public function getInterpreterName() {
-    return "phutil_test_block_interpreter";
+    return 'phutil_test_block_interpreter';
   }
 
   public function markupContent($content, array $argv) {
diff --git a/src/markup/syntax/highlighter/PhutilInvisibleSyntaxHighlighter.php b/src/markup/syntax/highlighter/PhutilInvisibleSyntaxHighlighter.php
--- a/src/markup/syntax/highlighter/PhutilInvisibleSyntaxHighlighter.php
+++ b/src/markup/syntax/highlighter/PhutilInvisibleSyntaxHighlighter.php
@@ -13,9 +13,9 @@
   }
 
   public function getHighlightFuture($source) {
-    $keys      = array_map("chr", range(0x0, 0x1F));
+    $keys      = array_map('chr', range(0x0, 0x1F));
     $vals      = array_map(
-      array($this, "decimalToHtmlEntityDecoded"), range(0x2400, 0x241F));
+      array($this, 'decimalToHtmlEntityDecoded'), range(0x2400, 0x241F));
 
     $invisible = array_combine($keys, $vals);
 
@@ -24,7 +24,7 @@
       if (isset($invisible[$character])) {
         $result[] = phutil_tag(
           'span',
-          array("class" => "invisible"),
+          array('class' => 'invisible'),
           $invisible[$character]);
 
         if ($character === "\n") {
diff --git a/src/parser/PhutilParserGenerator.php b/src/parser/PhutilParserGenerator.php
--- a/src/parser/PhutilParserGenerator.php
+++ b/src/parser/PhutilParserGenerator.php
@@ -118,28 +118,28 @@
 
   public function getEOFSymbol() {
     if ($this->eofSymbol === null) {
-      throw new Exception("Call processGrammar() before getEOFSymbol()!");
+      throw new Exception('Call processGrammar() before getEOFSymbol()!');
     }
     return $this->eofSymbol;
   }
 
   public function getInitSymbol() {
     if ($this->initSymbol === null) {
-      throw new Exception("Call processGrammar() before getInitSymbol()!");
+      throw new Exception('Call processGrammar() before getInitSymbol()!');
     }
     return $this->initSymbol;
   }
 
   public function getEpsilonSymbol() {
     if ($this->epsilonSymbol === null) {
-      throw new Exception("Call processGrammar() before getEpsilonSymbol()!");
+      throw new Exception('Call processGrammar() before getEpsilonSymbol()!');
     }
     return $this->epsilonSymbol;
   }
 
   public function getEndSymbol() {
     if ($this->endSymbol === null) {
-      throw new Exception("Call processGrammar() before getEndSymbol()!");
+      throw new Exception('Call processGrammar() before getEndSymbol()!');
     }
     return $this->endSymbol;
   }
@@ -319,7 +319,7 @@
       $missing_terminals = array_keys($missing);
       $missing_terminals = implode(', ', $missing_terminals);
       throw new PhutilParserGeneratorUnreachableTerminalException(
-        "Some terminals do not appear in any rule: ".
+        'Some terminals do not appear in any rule: '.
         $missing_terminals);
     }
   }
@@ -339,7 +339,7 @@
       $missing_rules = array_keys($missing);
       $missing_rules = implode(', ', $missing_rules);
       throw new PhutilParserGeneratorUnreachableRuleException(
-        "Some rules can never be reached from any production: ".
+        'Some rules can never be reached from any production: '.
         $missing_rules);
     }
   }
@@ -731,11 +731,11 @@
       }
 
       if ($accept && isset($shift[$eof])) {
-        throw new Exception("Accept/shift conflict!");
+        throw new Exception('Accept/shift conflict!');
       }
 
       if ($accept && isset($reduce[$eof])) {
-        throw new Exception("Accept/reduce conflict!");
+        throw new Exception('Accept/reduce conflict!');
       }
 
       foreach ($reduce as $next => $item) {
@@ -860,7 +860,7 @@
    */
   public function inspectRules() {
     if (!$this->rulesValidated) {
-      throw new Exception("Call processGrammar() before inspectRules()!");
+      throw new Exception('Call processGrammar() before inspectRules()!');
     }
     return $this->rules;
   }
@@ -871,7 +871,7 @@
    */
   public function inspectFirstTable() {
     if ($this->firstTable === null) {
-      throw new Exception("Call processGrammar() before inspectFirstTable()!");
+      throw new Exception('Call processGrammar() before inspectFirstTable()!');
     }
     return $this->firstTable;
   }
diff --git a/src/parser/PhutilQueryStringParser.php b/src/parser/PhutilQueryStringParser.php
--- a/src/parser/PhutilQueryStringParser.php
+++ b/src/parser/PhutilQueryStringParser.php
@@ -114,7 +114,7 @@
    */
   private function parseQueryKeyToArr($key, $val, array &$input_arr) {
     if (preg_match('/^[^\[\]]+(?:\[[^\[\]]*\])+$/', $key)) {
-      $key_pieces = preg_split('/\]?\[/', rtrim($key, "]"));
+      $key_pieces = preg_split('/\]?\[/', rtrim($key, ']'));
       if ($key_pieces) {
         $cursor     = &$input_arr;
         foreach ($key_pieces as $piece) {
diff --git a/src/parser/PhutilSimpleOptions.php b/src/parser/PhutilSimpleOptions.php
--- a/src/parser/PhutilSimpleOptions.php
+++ b/src/parser/PhutilSimpleOptions.php
@@ -177,7 +177,7 @@
 
   private function normalizeKey($key) {
     if (!strlen($key)) {
-      throw new Exception("Empty key is invalid!");
+      throw new Exception('Empty key is invalid!');
     }
     if (!$this->caseSensitive) {
       $key = strtolower($key);
diff --git a/src/parser/__tests__/PhutilDocblockParserTestCase.php b/src/parser/__tests__/PhutilDocblockParserTestCase.php
--- a/src/parser/__tests__/PhutilDocblockParserTestCase.php
+++ b/src/parser/__tests__/PhutilDocblockParserTestCase.php
@@ -32,23 +32,23 @@
       case 'indented-block.docblock':
         $this->assertEqual(array(), $specials);
         $this->assertEqual(
-          "Cozy lummox gives smart squid who asks for job pen.",
+          'Cozy lummox gives smart squid who asks for job pen.',
           $docblock);
         break;
       case 'indented-text.docblock':
         $this->assertEqual(array(), $specials);
         $this->assertEqual(
-          "Cozy lummox gives smart squid who asks for job pen.",
+          'Cozy lummox gives smart squid who asks for job pen.',
           $docblock);
         break;
       case 'multiline-special.docblock':
         $this->assertEqual(
           array(
-            'special' => "x y z",
+            'special' => 'x y z',
           ),
           $specials);
         $this->assertEqual(
-          "",
+          '',
           $docblock);
         break;
       case 'multi-specials.docblock':
@@ -58,7 +58,7 @@
           ),
           $specials);
         $this->assertEqual(
-          "",
+          '',
           $docblock);
         break;
       case 'specials.docblock':
@@ -69,7 +69,7 @@
           ),
           $specials);
         $this->assertEqual(
-          "",
+          '',
           $docblock);
         break;
       case 'linebreak-breaks-specials.docblock':
@@ -79,15 +79,15 @@
           ),
           $specials);
         $this->assertEqual(
-          "This is normal text, not part of the @title.",
+          'This is normal text, not part of the @title.',
           $docblock);
         break;
       case 'specials-with-hyphen.docblock':
         $this->assertEqual(
           array(
             'repeat-hyphen'     => "a\nb",
-            'multiline-hyphen'  => "mmm nnn",
-            'normal-hyphen'     => "x",
+            'multiline-hyphen'  => 'mmm nnn',
+            'normal-hyphen'     => 'x',
           ),
           $specials);
         break;
diff --git a/src/parser/__tests__/PhutilParserGeneratorTestCase.php b/src/parser/__tests__/PhutilParserGeneratorTestCase.php
--- a/src/parser/__tests__/PhutilParserGeneratorTestCase.php
+++ b/src/parser/__tests__/PhutilParserGeneratorTestCase.php
@@ -275,7 +275,7 @@
         break;
     }
 
-    throw new Exception("Unexpected rule in ET grammar.");
+    throw new Exception('Unexpected rule in ET grammar.');
   }
 
   private function buildABCGenerator() {
diff --git a/src/parser/__tests__/PhutilQueryStringParserTestCase.php b/src/parser/__tests__/PhutilQueryStringParserTestCase.php
--- a/src/parser/__tests__/PhutilQueryStringParserTestCase.php
+++ b/src/parser/__tests__/PhutilQueryStringParserTestCase.php
@@ -9,47 +9,47 @@
 
   public function testQueryStringParsing() {
     $map = array(
-      "" => array(),
-      "foo=bar&foobar=barfoo" => array(
-        "foo" => "bar",
-        "foobar" => "barfoo",
-      ),
-      "a]b[]=1&a]=2&a[[]=3&a[b]b=4&[][a]=5" => array(
-        "a]b[]" => "1",
-        "a]" => "2",
-        "a[[]" => "3",
-        "a[b]b" => "4",
-        "[][a]" => "5",
-      ),
-      "foo[][]=bar&bar[1][3]=foo" => array(
-        "foo" => array(
+      '' => array(),
+      'foo=bar&foobar=barfoo' => array(
+        'foo' => 'bar',
+        'foobar' => 'barfoo',
+      ),
+      'a]b[]=1&a]=2&a[[]=3&a[b]b=4&[][a]=5' => array(
+        'a]b[]' => '1',
+        'a]' => '2',
+        'a[[]' => '3',
+        'a[b]b' => '4',
+        '[][a]' => '5',
+      ),
+      'foo[][]=bar&bar[1][3]=foo' => array(
+        'foo' => array(
           0 => array(
-            0 => "bar",
+            0 => 'bar',
           ),
         ),
-        "bar" => array(
+        'bar' => array(
           1 => array(
-            3 => "foo",
+            3 => 'foo',
           ),
         ),
       ),
-      "foo[][]=bar&a]b[]=1" => array(
-        "foo" => array(
+      'foo[][]=bar&a]b[]=1' => array(
+        'foo' => array(
           0 => array(
-            0 => "bar",
+            0 => 'bar',
           ),
         ),
-        "a]b[]" => "1",
+        'a]b[]' => '1',
       ),
-      "a&&b" => array(
-        "a" => "",
-        "b" => "",
+      'a&&b' => array(
+        'a' => '',
+        'b' => '',
       ),
-      "a[b][]=foo&a[b][]=bar" => array(
-        "a" => array(
-          "b" => array(
-            0 => "foo",
-            1 => "bar",
+      'a[b][]=foo&a[b][]=bar' => array(
+        'a' => array(
+          'b' => array(
+            0 => 'foo',
+            1 => 'bar',
           ),
         ),
       ),
diff --git a/src/parser/__tests__/PhutilSimpleOptionsTestCase.php b/src/parser/__tests__/PhutilSimpleOptionsTestCase.php
--- a/src/parser/__tests__/PhutilSimpleOptionsTestCase.php
+++ b/src/parser/__tests__/PhutilSimpleOptionsTestCase.php
@@ -115,7 +115,7 @@
       $this->assertEqual(
         $expect,
         $parser->unparse($dict),
-        "Correct unparse of ".print_r($dict, true));
+        'Correct unparse of '.print_r($dict, true));
     }
 
     $bogus = array(
@@ -133,14 +133,14 @@
       }
       $this->assertTrue(
         $caught instanceof Exception,
-        "Correct throw on unparse of bad input.");
+        'Correct throw on unparse of bad input.');
     }
 
     $parser = new PhutilSimpleOptions();
     $this->assertEqual(
       'a="\\}"',
       $parser->unparse(array('a' => '}'), '}'),
-      "Unparse with extra escape.");
+      'Unparse with extra escape.');
   }
 
 }
diff --git a/src/parser/__tests__/PhutilTypeSpecTestCase.php b/src/parser/__tests__/PhutilTypeSpecTestCase.php
--- a/src/parser/__tests__/PhutilTypeSpecTestCase.php
+++ b/src/parser/__tests__/PhutilTypeSpecTestCase.php
@@ -121,21 +121,21 @@
   public function testGetTypeOf() {
     $map = array(
       'int'                     => 1,
-      'string'                  => "asdf",
+      'string'                  => 'asdf',
       'float'                   => 1.5,
       'bool'                    => true,
       'null'                    => null,
       'map<wild, wild>'         => array(),
-      'list<string>'            => array("a", "b"),
+      'list<string>'            => array('a', 'b'),
       'list<int>'               => array(1, 2, 3),
-      'map<string, int>'        => array("x" => 3),
-      'map<int, list<string>>'  => array(1 => array("x", "y")),
+      'map<string, int>'        => array('x' => 3),
+      'map<int, list<string>>'  => array(1 => array('x', 'y')),
       'stdClass'                => new stdClass(),
       'list<Exception>'         => array(
                                      new Exception(),
                                      new LogicException(),
                                      new RuntimeException()),
-      'map<string, stdClass>'   => array("x" => new stdClass()),
+      'map<string, stdClass>'   => array('x' => new stdClass()),
     );
 
     foreach ($map as $expect => $input) {
diff --git a/src/parser/aast/api/AASTNodeList.php b/src/parser/aast/api/AASTNodeList.php
--- a/src/parser/aast/api/AASTNodeList.php
+++ b/src/parser/aast/api/AASTNodeList.php
@@ -61,9 +61,9 @@
     }
 
     $desc = array();
-    $desc[] = "a list of ".count($this->list)." nodes:";
+    $desc[] = 'a list of '.count($this->list).' nodes:';
     foreach ($this->list as $node) {
-      $desc[] = '  '.$node->getDescription().";";
+      $desc[] = '  '.$node->getDescription().';';
     }
 
     return implode("\n", $desc);
diff --git a/src/parser/argument/PhutilArgumentParser.php b/src/parser/argument/PhutilArgumentParser.php
--- a/src/parser/argument/PhutilArgumentParser.php
+++ b/src/parser/argument/PhutilArgumentParser.php
@@ -324,7 +324,7 @@
 
       if ($name === null) {
         throw new PhutilArgumentSpecificationException(
-          "Workflow has no name!");
+          'Workflow has no name!');
       }
 
       if (isset($this->workflows[$name])) {
@@ -342,7 +342,7 @@
         $argv = array('help');
       } else {
         throw new PhutilArgumentUsageException(
-          "No workflow selected.");
+          'No workflow selected.');
       }
     }
 
@@ -358,7 +358,7 @@
       $command_list = implode(', ', $workflow_names);
       $ex_msg =
         "Invalid command '{$flow}'. Valid commands are: {$command_list}.";
-      if (in_array("help", $workflow_names)) {
+      if (in_array('help', $workflow_names)) {
         $bin = basename($this->bin);
         $ex_msg .=
           "\nFor more details on available commands, run `{$bin} help`.";
@@ -582,7 +582,7 @@
           $show_details = false);
       }
       if ($has_help) {
-        $more[] = "Use **help** __command__ for a detailed command reference.";
+        $more[] = 'Use **help** __command__ for a detailed command reference.';
       }
     }
 
@@ -597,7 +597,7 @@
     // a quick hint about it.
     if (!empty($this->specs['show-standard-options']) &&
         !$this->getArg('show-standard-options')) {
-      $more[] = "Use __--show-standard-options__ to show additional options.";
+      $more[] = 'Use __--show-standard-options__ to show additional options.';
     }
 
     $out[] = null;
@@ -706,8 +706,8 @@
       if ($spec->getWildcard()) {
         if ($wildcard) {
           throw new PhutilArgumentSpecificationException(
-            "Two argument specifications are marked as wildcard arguments. ".
-            "You can have a maximum of one wildcard argument.");
+            'Two argument specifications are marked as wildcard arguments. '.
+            'You can have a maximum of one wildcard argument.');
         } else {
           $wildcard = $spec;
         }
diff --git a/src/parser/argument/PhutilArgumentSpecification.php b/src/parser/argument/PhutilArgumentSpecification.php
--- a/src/parser/argument/PhutilArgumentSpecification.php
+++ b/src/parser/argument/PhutilArgumentSpecification.php
@@ -237,23 +237,23 @@
     if ($this->getWildcard()) {
       if ($this->getParamName()) {
         throw new PhutilArgumentSpecificationException(
-          "Wildcard arguments may not specify a parameter.");
+          'Wildcard arguments may not specify a parameter.');
       }
       if ($this->getRepeatable()) {
         throw new PhutilArgumentSpecificationException(
-          "Wildcard arguments may not be repeatable.");
+          'Wildcard arguments may not be repeatable.');
       }
     }
 
     if ($this->default !== null) {
       if ($this->getRepeatable()) {
         throw new PhutilArgumentSpecificationException(
-          "Repeatable arguments may not have a default (always array() for ".
-          "arguments which accept a parameter, or 0 for arguments which do ".
-          "not).");
+          'Repeatable arguments may not have a default (always array() for '.
+          'arguments which accept a parameter, or 0 for arguments which do '.
+          'not).');
       } else if ($this->getParamName() === null) {
         throw new PhutilArgumentSpecificationException(
-          "Flag arguments may not have a default (always false).");
+          'Flag arguments may not have a default (always false).');
       }
     }
   }
diff --git a/src/parser/argument/__tests__/PhutilArgumentSpecificationTestCase.php b/src/parser/argument/__tests__/PhutilArgumentSpecificationTestCase.php
--- a/src/parser/argument/__tests__/PhutilArgumentSpecificationTestCase.php
+++ b/src/parser/argument/__tests__/PhutilArgumentSpecificationTestCase.php
@@ -137,7 +137,7 @@
         $this->assertEqual(
           !$expect,
           $caught instanceof Exception,
-          "Spec validity for: ".print_r($spec, true));
+          'Spec validity for: '.print_r($spec, true));
       }
     }
   }
diff --git a/src/parser/argument/workflow/PhutilArgumentWorkflow.php b/src/parser/argument/workflow/PhutilArgumentWorkflow.php
--- a/src/parser/argument/workflow/PhutilArgumentWorkflow.php
+++ b/src/parser/argument/workflow/PhutilArgumentWorkflow.php
@@ -112,7 +112,7 @@
 
   final public function getExamples() {
     if (!$this->examples) {
-      return "**".$this->name."**";
+      return '**'.$this->name.'**';
     }
     return $this->examples;
   }
diff --git a/src/parser/exception/PhutilTypeCheckException.php b/src/parser/exception/PhutilTypeCheckException.php
--- a/src/parser/exception/PhutilTypeCheckException.php
+++ b/src/parser/exception/PhutilTypeCheckException.php
@@ -13,7 +13,7 @@
         "Parameter '%s' has invalid type.",
         $name);
     } else {
-      $invalid = pht("Parameter has invalid type.");
+      $invalid = pht('Parameter has invalid type.');
     }
 
     if ($type->getType() == 'regex') {
@@ -24,7 +24,7 @@
           $err);
       } else {
         $message = pht(
-          "Expected a regular expression, but value is not valid: %s",
+          'Expected a regular expression, but value is not valid: %s',
           $err);
       }
     } else {
diff --git a/src/parser/xhpast/api/XHPASTNode.php b/src/parser/xhpast/api/XHPASTNode.php
--- a/src/parser/xhpast/api/XHPASTNode.php
+++ b/src/parser/xhpast/api/XHPASTNode.php
@@ -72,7 +72,7 @@
             return $operand->evalStatic();
             break;
           default:
-            throw new Exception("Unexpected operator in static expression.");
+            throw new Exception('Unexpected operator in static expression.');
         }
         break;
       case 'n_ARRAY_LITERAL':
diff --git a/src/parser/xhpast/api/XHPASTTree.php b/src/parser/xhpast/api/XHPASTTree.php
--- a/src/parser/xhpast/api/XHPASTTree.php
+++ b/src/parser/xhpast/api/XHPASTTree.php
@@ -38,7 +38,7 @@
     $tree = XHPASTTree::newFromData($string);
     $statements = $tree->getRootNode()->selectDescendantsOfType('n_STATEMENT');
     if (count($statements) != 1) {
-      throw new Exception("String does not parse into exactly one statement!");
+      throw new Exception('String does not parse into exactly one statement!');
     }
     // Return the first one, trying to use reset() with iterators ends in tears.
     foreach ($statements as $statement) {
@@ -67,7 +67,7 @@
 
     $data = json_decode($stdout, true);
     if (!is_array($data)) {
-      throw new Exception("XHPAST: failed to decode tree.");
+      throw new Exception('XHPAST: failed to decode tree.');
     }
 
     return new XHPASTTree($data['tree'], $data['stream'], $php_source);
diff --git a/src/parser/xhpast/bin/xhpast_parse.php b/src/parser/xhpast/bin/xhpast_parse.php
--- a/src/parser/xhpast/bin/xhpast_parse.php
+++ b/src/parser/xhpast/bin/xhpast_parse.php
@@ -12,7 +12,7 @@
       list($err, $stdout) = exec_manual('%s --version', $bin);
       if (!$err) {
         $version = trim($stdout);
-        if ($version === "xhpast version 5.5.8/1e") {
+        if ($version === 'xhpast version 5.5.8/1e') {
           $available = true;
         }
       }
diff --git a/src/phage/agent/PhagePHPAgent.php b/src/phage/agent/PhagePHPAgent.php
--- a/src/phage/agent/PhagePHPAgent.php
+++ b/src/phage/agent/PhagePHPAgent.php
@@ -48,7 +48,7 @@
 
     $open = $channel->update();
     if (!$open) {
-      throw new Exception("Channel closed!");
+      throw new Exception('Channel closed!');
     }
 
     while (true) {
diff --git a/src/phage/bootloader/PhagePHPAgentBootloader.php b/src/phage/bootloader/PhagePHPAgentBootloader.php
--- a/src/phage/bootloader/PhagePHPAgentBootloader.php
+++ b/src/phage/bootloader/PhagePHPAgentBootloader.php
@@ -82,7 +82,7 @@
       $boot_sequence->addText($main_sequence->toString());
 
       if (strlen($boot_length) > 8192) {
-        throw new Exception("Stage 1 bootloader is too large!");
+        throw new Exception('Stage 1 bootloader is too large!');
       }
 
       $this->bootSequence = $boot_sequence;
diff --git a/src/utils/AbstractDirectedGraph.php b/src/utils/AbstractDirectedGraph.php
--- a/src/utils/AbstractDirectedGraph.php
+++ b/src/utils/AbstractDirectedGraph.php
@@ -75,8 +75,8 @@
   final public function addNodes(array $nodes) {
     if ($this->graphLoaded) {
       throw new Exception(
-        "Call addNodes() before calling loadGraph(). You can not add more ".
-        "nodes once you have loaded the graph.");
+        'Call addNodes() before calling loadGraph(). You can not add more '.
+        'nodes once you have loaded the graph.');
     }
 
     $this->knownNodes += $nodes;
@@ -172,8 +172,8 @@
       foreach ($load as $node) {
         if (!isset($new_nodes[$node]) || !is_array($new_nodes[$node])) {
           throw new Exception(
-            "loadEdges() must return an edge list array for each provided ".
-            "node, or the cycle detection algorithm may not terminate.");
+            'loadEdges() must return an edge list array for each provided '.
+            'node, or the cycle detection algorithm may not terminate.');
         }
       }
 
@@ -216,8 +216,8 @@
   final public function detectCycles($node) {
     if (!$this->graphLoaded) {
       throw new Exception(
-        "Call loadGraph() to build the graph out before calling ".
-        "detectCycles().");
+        'Call loadGraph() to build the graph out before calling '.
+        'detectCycles().');
     }
     if (!isset($this->knownNodes[$node])) {
       throw new Exception(
diff --git a/src/utils/PhutilDirectedScalarGraph.php b/src/utils/PhutilDirectedScalarGraph.php
--- a/src/utils/PhutilDirectedScalarGraph.php
+++ b/src/utils/PhutilDirectedScalarGraph.php
@@ -8,8 +8,8 @@
 
   protected function loadEdges(array $nodes) {
     throw new Exception(
-      "PhutilDirectedScalarGraph can not load additional nodes at runtime. ".
-      "Tried to load: ".implode(', ', $nodes));
+      'PhutilDirectedScalarGraph can not load additional nodes at runtime. '.
+      'Tried to load: '.implode(', ', $nodes));
   }
 
 }
diff --git a/src/utils/PhutilEditDistanceMatrix.php b/src/utils/PhutilEditDistanceMatrix.php
--- a/src/utils/PhutilEditDistanceMatrix.php
+++ b/src/utils/PhutilEditDistanceMatrix.php
@@ -166,7 +166,7 @@
   private function requireSequences() {
     if ($this->x === null) {
       throw new Exception(
-        "Call setSequences() before performing useful work!");
+        'Call setSequences() before performing useful work!');
     }
   }
 
@@ -293,7 +293,7 @@
   private function getTypeMatrix() {
     if (!$this->computeString) {
       throw new Exception(
-        "Call setComputeString() before getTypeMatrix().");
+        'Call setComputeString() before getTypeMatrix().');
     }
     if ($this->typeMatrix === null) {
       $this->computeMatrix($this->x, $this->y);
@@ -366,8 +366,8 @@
     $alt_cost = $this->getAlterCost();
     if ($alt_cost && !$use_types) {
       throw new Exception(
-        "If you provide an alter cost with setAlterCost(), you must enable ".
-        "type computation with setComputeStrings().");
+        'If you provide an alter cost with setAlterCost(), you must enable '.
+        'type computation with setComputeStrings().');
     }
 
     // Build the edit distance matrix.
diff --git a/src/utils/__tests__/PhutilEditDistanceMatrixTestCase.php b/src/utils/__tests__/PhutilEditDistanceMatrixTestCase.php
--- a/src/utils/__tests__/PhutilEditDistanceMatrixTestCase.php
+++ b/src/utils/__tests__/PhutilEditDistanceMatrixTestCase.php
@@ -43,9 +43,9 @@
     // Misc.
     $this->assertDistance(
       13,
-      "The quick brown fox jumped over the lazy dog!",
+      'The quick brown fox jumped over the lazy dog!',
       //   dddddd          r            ii         i iii
-      "The brown fox pumped over those lazy dogs!~~~");
+      'The brown fox pumped over those lazy dogs!~~~');
   }
 
   public function testDamerauEditDistance() {
diff --git a/src/utils/__tests__/PhutilUTF8TestCase.php b/src/utils/__tests__/PhutilUTF8TestCase.php
--- a/src/utils/__tests__/PhutilUTF8TestCase.php
+++ b/src/utils/__tests__/PhutilUTF8TestCase.php
@@ -50,7 +50,7 @@
       'x'               => 1,
       "\xEF\xBF\xBD"    => 1,
       "x\xe6\x9d\xb1y"  => 3,
-      "xyz"             => 3,
+      'xyz'             => 3,
       'quack'           => 5,
     );
     foreach ($strings as $str => $expect) {
@@ -66,7 +66,7 @@
       "x\xe6\x9d\xb1y"    => array('x', "\xe6\x9d\xb1", 'y'),
 
       // This is a combining character.
-      "x\xCD\xA0y"        => array("x", "\xCD\xA0", 'y'),
+      "x\xCD\xA0y"        => array('x', "\xCD\xA0", 'y'),
     );
     foreach ($strings as $str => $expect) {
       $this->assertEqual($expect, phutil_utf8v($str), 'Vector of '.$str);
@@ -98,9 +98,9 @@
 
   public function testUTF8ConsoleStrlen() {
     $strings = array(
-      ""              => 0,
+      ''              => 0,
       "\0"            => 0,
-      "x"             => 1,
+      'x'             => 1,
 
       // Double-width chinese character.
       "\xe6\x9d\xb1"  => 2,
@@ -115,34 +115,34 @@
 
   public function testUTF8shorten() {
     $inputs = array(
-      array("1erp derp derp", 9, "", "1erp derp"),
-      array("2erp derp derp", 12, "...", "2erp derp..."),
-      array("derpxderpxderp", 12, "...", "derpxderp..."),
-      array("derp\xE2\x99\x83derpderp", 12, "...", "derp\xE2\x99\x83derp..."),
-      array("", 12, "...", ""),
-      array("derp", 12, "...", "derp"),
-      array("11111", 5, "2222", "11111"),
-      array("111111", 5, "2222", "12222"),
-
-      array("D1rp. Derp derp.", 7, "...", "D1rp."),
-      array("D2rp. Derp derp.", 5, "...", "D2rp."),
-      array("D3rp. Derp derp.", 4, "...", "D..."),
-      array("D4rp. Derp derp.", 14, "...", "D4rp. Derp..."),
-      array("D5rpderp, derp derp", 16, "...", "D5rpderp..."),
-      array("D6rpderp, derp derp", 17, "...", "D6rpderp, derp..."),
+      array('1erp derp derp', 9, '', '1erp derp'),
+      array('2erp derp derp', 12, '...', '2erp derp...'),
+      array('derpxderpxderp', 12, '...', 'derpxderp...'),
+      array("derp\xE2\x99\x83derpderp", 12, '...', "derp\xE2\x99\x83derp..."),
+      array('', 12, '...', ''),
+      array('derp', 12, '...', 'derp'),
+      array('11111', 5, '2222', '11111'),
+      array('111111', 5, '2222', '12222'),
+
+      array('D1rp. Derp derp.', 7, '...', 'D1rp.'),
+      array('D2rp. Derp derp.', 5, '...', 'D2rp.'),
+      array('D3rp. Derp derp.', 4, '...', 'D...'),
+      array('D4rp. Derp derp.', 14, '...', 'D4rp. Derp...'),
+      array('D5rpderp, derp derp', 16, '...', 'D5rpderp...'),
+      array('D6rpderp, derp derp', 17, '...', 'D6rpderp, derp...'),
 
       // Strings with combining characters.
-      array("Gr\xCD\xA0mpyCatSmiles", 8, "...", "Gr\xCD\xA0mpy..."),
-      array("X\xCD\xA0\xCD\xA0\xCD\xA0Y", 1, "", "X\xCD\xA0\xCD\xA0\xCD\xA0"),
+      array("Gr\xCD\xA0mpyCatSmiles", 8, '...', "Gr\xCD\xA0mpy..."),
+      array("X\xCD\xA0\xCD\xA0\xCD\xA0Y", 1, '', "X\xCD\xA0\xCD\xA0\xCD\xA0"),
 
       // This behavior is maybe a little bad, but it seems mostly reasonable,
       // at least for latin languages.
-      array("Derp, supercalafragalisticexpialadoshus", 30, "...",
-              "Derp..."),
+      array('Derp, supercalafragalisticexpialadoshus', 30, '...',
+              'Derp...'),
 
       // If a string has only word-break characters in it, we should just cut
       // it, not produce only the terminal.
-      array("((((((((((", 8, '...', '(((((...'),
+      array('((((((((((', 8, '...', '(((((...'),
 
       // Terminal is longer than requested input.
       array('derp', 3, 'quack', 'quack'),
@@ -291,7 +291,7 @@
 
   public function testUTF8Convert() {
     if (!function_exists('mb_convert_encoding')) {
-      $this->assertSkipped("Requires mbstring extension.");
+      $this->assertSkipped('Requires mbstring extension.');
     }
 
     // "[ae]gis se[n]or [(c)] 1970 [+/-] 1 [degree]"
@@ -441,30 +441,30 @@
 
   public function testUTF8BMP() {
     $tests = array(
-      ""  => array(true, true, "empty string"),
-      "a" => array(true, true, "a"),
-      "a\xCD\xA0\xCD\xA0" => array(true, true, "a with combining"),
-      "\xE2\x98\x83" => array(true, true, "snowman"),
+      ''  => array(true, true, 'empty string'),
+      'a' => array(true, true, 'a'),
+      "a\xCD\xA0\xCD\xA0" => array(true, true, 'a with combining'),
+      "\xE2\x98\x83" => array(true, true, 'snowman'),
 
       // This is the last character in BMP, U+FFFF.
-      "\xEF\xBF\xBF" => array(true, true, "U+FFFF"),
+      "\xEF\xBF\xBF" => array(true, true, 'U+FFFF'),
 
       // This isn't valid.
-      "\xEF\xBF\xC0" => array(false, false, "Invalid, byte range."),
+      "\xEF\xBF\xC0" => array(false, false, 'Invalid, byte range.'),
 
       // This is the first character above BMP, U+10000.
-      "\xF0\x90\x80\x80" => array(true, false, "U+10000"),
-      "\xF0\x9D\x84\x9E" => array(true, false, "gclef"),
+      "\xF0\x90\x80\x80" => array(true, false, 'U+10000'),
+      "\xF0\x9D\x84\x9E" => array(true, false, 'gclef'),
 
-      "musical \xF0\x9D\x84\x9E g-clef" => array(true, false, "gclef text"),
-      "\xF0\x9D\x84" => array(false, false, "Invalid, truncated."),
+      "musical \xF0\x9D\x84\x9E g-clef" => array(true, false, 'gclef text'),
+      "\xF0\x9D\x84" => array(false, false, 'Invalid, truncated.'),
 
-      "\xE0\x80\x80" => array(false, false, "Nonminimal 3-byte character."),
+      "\xE0\x80\x80" => array(false, false, 'Nonminimal 3-byte character.'),
 
       // Partial BMP characters.
-      "\xCD" => array(false, false, "Partial 2-byte character."),
-      "\xE0\xA0" => array(false, false, "Partial BMP 0xE0 character."),
-      "\xE2\x98" => array(false, false, "Partial BMP cahracter."),
+      "\xCD" => array(false, false, 'Partial 2-byte character.'),
+      "\xE0\xA0" => array(false, false, 'Partial BMP 0xE0 character.'),
+      "\xE2\x98" => array(false, false, 'Partial BMP cahracter.'),
     );
 
     foreach ($tests as $input => $test) {
diff --git a/src/utils/__tests__/PhutilUtilsTestCase.php b/src/utils/__tests__/PhutilUtilsTestCase.php
--- a/src/utils/__tests__/PhutilUtilsTestCase.php
+++ b/src/utils/__tests__/PhutilUtilsTestCase.php
@@ -226,11 +226,11 @@
 
     $this->assertEqual(
       null,
-      assert_stringlike(""));
+      assert_stringlike(''));
 
     $this->assertEqual(
       null,
-      assert_stringlike("Hello World"));
+      assert_stringlike('Hello World'));
 
     $this->assertEqual(
       null,
@@ -260,8 +260,8 @@
     $this->assertTrue($caught instanceof InvalidArgumentException);
 
     $array = array(
-             "foo" => "bar",
-             "bar" => "foo",
+             'foo' => 'bar',
+             'bar' => 'foo',
              );
 
     try {
@@ -345,8 +345,8 @@
 
   public function testSplitLines() {
     $retain_cases = array(
-      "" => array(""),
-      "x" => array("x"),
+      '' => array(''),
+      'x' => array('x'),
       "x\n" => array("x\n"),
       "\n" => array("\n"),
       "\n\n\n" => array("\n", "\n", "\n"),
@@ -364,15 +364,15 @@
     }
 
     $discard_cases = array(
-      "" => array(""),
-      "x" => array("x"),
-      "x\n" => array("x"),
-      "\n" => array(""),
-      "\n\n\n" => array("", "", ""),
-      "\r\n" => array(""),
-      "x\r\ny\n" => array("x", "y"),
-      "x\ry\nz\r\n" => array("x\ry", "z"),
-      "x\ry\nz\r\n\n" => array("x\ry", "z", ""),
+      '' => array(''),
+      'x' => array('x'),
+      "x\n" => array('x'),
+      "\n" => array(''),
+      "\n\n\n" => array('', '', ''),
+      "\r\n" => array(''),
+      "x\r\ny\n" => array('x', 'y'),
+      "x\ry\nz\r\n" => array("x\ry", 'z'),
+      "x\ry\nz\r\n\n" => array("x\ry", 'z', ''),
     );
 
     foreach ($discard_cases as $input => $expect) {
@@ -435,8 +435,8 @@
 
   public function testLoggableString() {
     $this->assertEqual(
-      "",
-      phutil_loggable_string(""));
+      '',
+      phutil_loggable_string(''));
 
     $this->assertEqual(
       "a\\nb",
diff --git a/src/utils/utf8.php b/src/utils/utf8.php
--- a/src/utils/utf8.php
+++ b/src/utils/utf8.php
@@ -238,7 +238,7 @@
       $ii += 1;
       continue;
     } else if ($byte < "\xC0") {
-      throw new Exception("Invalid UTF-8 string passed to phutil_utf8v().");
+      throw new Exception('Invalid UTF-8 string passed to phutil_utf8v().');
     } else if ($byte <= "\xDF") {
       $seq_len = 2;
     } else if ($byte <= "\xEF") {
@@ -250,15 +250,15 @@
     } else if ($byte <= "\xFD") {
       $seq_len = 6;
     } else {
-      throw new Exception("Invalid UTF-8 string passed to phutil_utf8v().");
+      throw new Exception('Invalid UTF-8 string passed to phutil_utf8v().');
     }
 
     if ($ii + $seq_len > $len) {
-      throw new Exception("Invalid UTF-8 string passed to phutil_utf8v().");
+      throw new Exception('Invalid UTF-8 string passed to phutil_utf8v().');
     }
     for ($jj = 1; $jj < $seq_len; ++$jj) {
       if ($string[$ii + $jj] >= "\xC0") {
-        throw new Exception("Invalid UTF-8 string passed to phutil_utf8v().");
+        throw new Exception('Invalid UTF-8 string passed to phutil_utf8v().');
       }
     }
     $res[] = substr($string, $ii, $seq_len);
@@ -541,13 +541,13 @@
 function phutil_utf8_convert($string, $to_encoding, $from_encoding) {
   if (!$from_encoding) {
     throw new InvalidArgumentException(
-      "Attempting to convert a string encoding, but no source encoding ".
-      "was provided. Explicitly provide the source encoding.");
+      'Attempting to convert a string encoding, but no source encoding '.
+      'was provided. Explicitly provide the source encoding.');
   }
   if (!$to_encoding) {
     throw new InvalidArgumentException(
-      "Attempting to convert a string encoding, but no target encoding ".
-      "was provided. Explicitly provide the target encoding.");
+      'Attempting to convert a string encoding, but no target encoding '.
+      'was provided. Explicitly provide the target encoding.');
   }
 
   // Normalize encoding names so we can no-op the very common case of UTF8
@@ -752,7 +752,7 @@
   if (
     $array_length > 0 &&
     phutil_utf8_is_combining_character($components[0])) {
-    $string = " ".$string;
+    $string = ' '.$string;
     $components = phutil_utf8v($string);
     $array_length++;
   }
diff --git a/src/utils/utils.php b/src/utils/utils.php
--- a/src/utils/utils.php
+++ b/src/utils/utils.php
@@ -577,7 +577,7 @@
   }
 
   throw new InvalidArgumentException(
-    "Argument must be scalar or object which implements __toString()!");
+    'Argument must be scalar or object which implements __toString()!');
 }
 
 /**
@@ -854,7 +854,7 @@
 function phutil_exit($status = 0) {
   $event = new PhutilEvent(
     PhutilEventType::TYPE_WILLEXITABRUPTLY,
-    array("status" => $status));
+    array('status' => $status));
   PhutilEventEngine::dispatchEvent($event);
 
   exit($status);
@@ -875,7 +875,7 @@
   $result = '';
 
   static $c_map = array(
-    "\\" => '\\\\',
+    '\\' => '\\\\',
     "\n" => '\\n',
     "\r" => '\\r',
     "\t" => '\\t',
diff --git a/src/xsprintf/csprintf.php b/src/xsprintf/csprintf.php
--- a/src/xsprintf/csprintf.php
+++ b/src/xsprintf/csprintf.php
@@ -80,7 +80,7 @@
 
       // Check that the value is a non-empty array.
       if (!is_array($value)) {
-        throw new Exception("Expected an array for %Ls conversion.");
+        throw new Exception('Expected an array for %Ls conversion.');
       }
 
       // Convert the list of strings to a single string.
@@ -99,7 +99,7 @@
     case 'P':
       if (!($value instanceof PhutilOpaqueEnvelope)) {
         throw new Exception(
-          "Expected PhutilOpaqueEnvelope for %P conversion.");
+          'Expected PhutilOpaqueEnvelope for %P conversion.');
       }
       if ($is_unmasked) {
         $value = $value->openEnvelope();
diff --git a/src/xsprintf/qsprintf.php b/src/xsprintf/qsprintf.php
--- a/src/xsprintf/qsprintf.php
+++ b/src/xsprintf/qsprintf.php
@@ -90,7 +90,7 @@
   $prefix   = '';
 
   if (!($escaper instanceof PhutilQsprintfInterface)) {
-    throw new Exception("Invalid database escaper!");
+    throw new Exception('Invalid database escaper!');
   }
 
   switch ($type) {
diff --git a/src/xsprintf/xsprintf.php b/src/xsprintf/xsprintf.php
--- a/src/xsprintf/xsprintf.php
+++ b/src/xsprintf/xsprintf.php
@@ -57,7 +57,7 @@
 
         $arg++;
         if ($arg >= $argc) {
-          throw new Exception("Too few arguments to xsprintf().");
+          throw new Exception('Too few arguments to xsprintf().');
         }
 
         $callback($userdata, $pattern, $pos, $argv[$arg], $len);
@@ -72,7 +72,7 @@
   }
 
   if ($arg != ($argc - 1)) {
-    throw new Exception("Too many arguments to xsprintf().");
+    throw new Exception('Too many arguments to xsprintf().');
   }
 
   $argv[0] = $pattern;
@@ -112,6 +112,6 @@
   &$value,
   &$length) {
   throw new Exception(
-    "This function exists only to document the call signature for xsprintf() ".
-    "callbacks.");
+    'This function exists only to document the call signature for xsprintf() '.
+    'callbacks.');
 }