diff --git a/autoload.php b/autoload.php
index 6bb5f11..260e06a 100644
--- a/autoload.php
+++ b/autoload.php
@@ -1,3 +1,3 @@
 <?php
 require_once __DIR__.DIRECTORY_SEPARATOR."bootstrap.php";
-$data = new RuntimeData(new Conf());
\ No newline at end of file
+Data::load(new Conf());
\ No newline at end of file
diff --git a/lib/AbstractException.php b/lib/AbstractException.php
index cac5a63..7476699 100644
--- a/lib/AbstractException.php
+++ b/lib/AbstractException.php
@@ -6,7 +6,6 @@ abstract class AbstractException extends \Exception {
 
     const CODES = [
         "Exception.uncoded"                     => -1,
-        "Exception.invalid"                     => 1, // this exception MUST NOT have a message string defined
         "Exception.unknown"                     => 10000,
         "Lang/Exception.defaultFileMissing"     => 10101,
         "Lang/Exception.fileMissing"            => 10102,
@@ -79,7 +78,7 @@ abstract class AbstractException extends \Exception {
                 $code = self::CODES[$codeID];
                 $msg = "Exception.".str_replace("\\", "/", $class).".$msgID";
             }
-            $msg = Lang::msg($msg, $vars);
+            $msg = Data::$l->msg($msg, $vars);
         }
         parent::__construct($msg, $code, $e);
     }
diff --git a/lib/Data.php b/lib/Data.php
new file mode 100644
index 0000000..30b981b
--- /dev/null
+++ b/lib/Data.php
@@ -0,0 +1,18 @@
+<?php
+declare(strict_types=1);
+namespace JKingWeb\Arsse;
+
+class Data {
+    public static $l;
+    public static $conf;
+    public static $db;
+    public static $user;
+
+    static function load(Conf $conf) {
+        static::$l = new Lang();
+        static::$conf = $conf;
+        static::$l->set($conf->lang);
+        static::$db = new Database();
+        static::$user = new User();
+    }
+}
\ No newline at end of file
diff --git a/lib/Database.php b/lib/Database.php
index 95ad416..d683fda 100644
--- a/lib/Database.php
+++ b/lib/Database.php
@@ -18,10 +18,9 @@ class Database {
         return (string) preg_filter("[^0-9a-zA-Z_\.]", "", $name);
     }
 
-    public function __construct(RuntimeData $data) {
-        $this->data = $data;
-        $this->driver = $driver = $data->conf->dbDriver;
-        $this->db = new $driver($data, INSTALL);
+    public function __construct() {
+        $this->driver = $driver = Data::$conf->dbDriver;
+        $this->db = new $driver(INSTALL);
         $ver = $this->db->schemaVersion();
         if(!INSTALL && $ver < self::SCHEMA_VERSION) {
             $this->db->schemaUpdate(self::SCHEMA_VERSION);
@@ -166,14 +165,14 @@ class Database {
     }
 
     public function userExists(string $user): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         return (bool) $this->db->prepare("SELECT count(*) from arsse_users where id is ?", "str")->run($user)->getValue();
     }
 
     public function userAdd(string $user, string $password = null): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if($this->userExists($user)) throw new User\Exception("alreadyExists", ["action" => __FUNCTION__, "user" => $user]);
-        if($password===null) $password = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($password===null) $password = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         $hash = "";
         if(strlen($password) > 0) $hash = password_hash($password, \PASSWORD_DEFAULT);
         $this->db->prepare("INSERT INTO arsse_users(id,password) values(?,?)", "str", "str")->runArray([$user,$hash]);
@@ -181,33 +180,33 @@ class Database {
     }
 
     public function userRemove(string $user): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if($this->db->prepare("DELETE from arsse_users where id is ?", "str")->run($user)->changes() < 1) throw new User\Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return true;
     }
 
     public function userList(string $domain = null): array {
         if($domain !== null) {
-            if(!$this->data->user->authorize("@".$domain, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $domain]);
+            if(!Data::$user->authorize("@".$domain, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $domain]);
             $domain = str_replace(["\\","%","_"],["\\\\", "\\%", "\\_"], $domain);
             $domain = "%@".$domain;
             return $this->db->prepare("SELECT id from arsse_users where id like ?", "str")->run($domain)->getAll();
         } else {
-            if(!$this->data->user->authorize("", __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => "global"]);
+            if(!Data::$user->authorize("", __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => "global"]);
             return $this->db->prepare("SELECT id from arsse_users")->run()->getAll();
         }
     }
 
     public function userPasswordGet(string $user): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new User\Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return (string) $this->db->prepare("SELECT password from arsse_users where id is ?", "str")->run($user)->getValue();
     }
 
     public function userPasswordSet(string $user, string $password = null): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new User\Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
-        if($password===null) $password = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($password===null) $password = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         $hash = "";
         if(strlen($password > 0)) $hash = password_hash($password, \PASSWORD_DEFAULT);
         $this->db->prepare("UPDATE arsse_users set password = ? where id is ?", "str", "str")->run($hash, $user);
@@ -215,14 +214,14 @@ class Database {
     }
 
     public function userPropertiesGet(string $user): array {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         $prop = $this->db->prepare("SELECT name,rights from arsse_users where id is ?", "str")->run($user)->getRow();
         if(!$prop) return [];
         return $prop;
     }
 
     public function userPropertiesSet(string $user, array &$properties): array {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         $valid = [ // FIXME: add future properties
             "name" => "str",
         ];
@@ -237,12 +236,12 @@ class Database {
     }
 
     public function userRightsGet(string $user): int {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         return (int) $this->db->prepare("SELECT rights from arsse_users where id is ?", "str")->run($user)->getValue();
     }
 
     public function userRightsSet(string $user, int $rights): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__, $rights)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__, $rights)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) return false;
         $this->db->prepare("UPDATE arsse_users set rights = ? where id is ?", "int", "str")->run($rights, $user);
         return true;
@@ -250,7 +249,7 @@ class Database {
 
     public function subscriptionAdd(string $user, string $url, string $fetchUser = "", string $fetchPassword = ""): int {
         // If the user isn't authorized to perform this action then throw an exception.
-        if (!$this->data->user->authorize($user, __FUNCTION__)) {
+        if (!Data::$user->authorize($user, __FUNCTION__)) {
             throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         }
         // If the user doesn't exist throw an exception.
@@ -299,13 +298,13 @@ class Database {
     }
 
     public function subscriptionRemove(string $user, int $id): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         return (bool) $this->db->prepare("DELETE from arsse_subscriptions where id is ?", "int")->run($id)->changes();
     }
 
     public function folderAdd(string $user, array $data): int {
         // If the user isn't authorized to perform this action then throw an exception.
-        if (!$this->data->user->authorize($user, __FUNCTION__)) {
+        if (!Data::$user->authorize($user, __FUNCTION__)) {
             throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         }
         // If the user doesn't exist throw an exception.
@@ -345,7 +344,7 @@ class Database {
 
     public function folderList(string $user, int $parent = null, bool $recursive = true): Db\Result {
         // if the user isn't authorized to perform this action then throw an exception.
-        if (!$this->data->user->authorize($user, __FUNCTION__)) {
+        if (!Data::$user->authorize($user, __FUNCTION__)) {
             throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         }
         // if the user doesn't exist throw an exception.
@@ -487,7 +486,7 @@ class Database {
     }
 
     public function folderRemove(string $user, int $id): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new User\ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         // common table expression to list all descendant folders of the target folder
         $cte = "RECURSIVE folders(id) as (SELECT id from arsse_folders where owner is ? and id is ? union select arsse_folders.id from arsse_folders join folders on arsse_folders.parent=folders.id) ";
         $changes = 0;
diff --git a/lib/Db/Driver.php b/lib/Db/Driver.php
index 115c529..0f0f02b 100644
--- a/lib/Db/Driver.php
+++ b/lib/Db/Driver.php
@@ -3,7 +3,7 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\Db;
 
 interface Driver {
-    function __construct(\JKingWeb\Arsse\RuntimeData $data, bool $install = false);
+    function __construct(bool $install = false);
     // returns a human-friendly name for the driver (for display in installer, for example)
     static function driverName(): string;
     // returns the version of the scheme of the opened database; if uninitialized should return 0
diff --git a/lib/Db/SQLite3/Driver.php b/lib/Db/SQLite3/Driver.php
index bdbcf05..37c4c57 100644
--- a/lib/Db/SQLite3/Driver.php
+++ b/lib/Db/SQLite3/Driver.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Db\SQLite3;
-use JKingWeb\Arsse\Lang;
+use JKingWeb\Arsse\Data;
 use JKingWeb\Arsse\Db\Exception;
 use JKingWeb\Arsse\Db\ExceptionInput;
 use JKingWeb\Arsse\Db\ExceptionTimeout;
@@ -15,16 +15,14 @@ class Driver extends \JKingWeb\Arsse\Db\AbstractDriver {
     const SQLITE_MISMATCH = 20;
 
     protected $db;
-    protected $data;
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data, bool $install = false) {
+    public function __construct(bool $install = false) {
         // check to make sure required extension is loaded
         if(!class_exists("SQLite3")) throw new Exception("extMissing", self::driverName());
-        $this->data = $data;
-        $file = $data->conf->dbSQLite3File;
+        $file = Data::$conf->dbSQLite3File;
         // if the file exists (or we're initializing the database), try to open it
         try {
-            $this->db = new \SQLite3($file, ($install) ? \SQLITE3_OPEN_READWRITE | \SQLITE3_OPEN_CREATE : \SQLITE3_OPEN_READWRITE, $data->conf->dbSQLite3Key);
+            $this->db = new \SQLite3($file, ($install) ? \SQLITE3_OPEN_READWRITE | \SQLITE3_OPEN_CREATE : \SQLITE3_OPEN_READWRITE, Data::$conf->dbSQLite3Key);
         } catch(\Throwable $e) {
             // if opening the database doesn't work, check various pre-conditions to find out what the problem might be
             if(!file_exists($file)) {
@@ -57,7 +55,7 @@ class Driver extends \JKingWeb\Arsse\Db\AbstractDriver {
 
 
     static public function driverName(): string {
-        return Lang::msg("Driver.Db.SQLite3.Name");
+        return Data::$l->msg("Driver.Db.SQLite3.Name");
     }
 
     public function schemaVersion(): int {
@@ -66,10 +64,10 @@ class Driver extends \JKingWeb\Arsse\Db\AbstractDriver {
 
     public function schemaUpdate(int $to): bool {
         $ver = $this->schemaVersion();
-        if(!$this->data->conf->dbSQLite3AutoUpd)  throw new Exception("updateManual", ['version' => $ver, 'driver_name' => $this->driverName()]);
+        if(!Data::$conf->dbSQLite3AutoUpd)  throw new Exception("updateManual", ['version' => $ver, 'driver_name' => $this->driverName()]);
         if($ver >= $to) throw new Exception("updateTooNew", ['difference' => ($ver - $to), 'current' => $ver, 'target' => $to, 'driver_name' => $this->driverName()]);
         $sep = \DIRECTORY_SEPARATOR;
-        $path = $this->data->conf->dbSchemaBase.$sep."SQLite3".$sep;
+        $path = Data::$conf->dbSchemaBase.$sep."SQLite3".$sep;
         $this->lock();
         $this->begin();
         for($a = $ver; $a < $to; $a++) {
diff --git a/lib/Lang.php b/lib/Lang.php
index 1a2f9c1..1ca84e1 100644
--- a/lib/Lang.php
+++ b/lib/Lang.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \Webmozart\Glob\Glob;
+use Webmozart\Glob\Glob;
 
 class Lang {
     const DEFAULT = "en"; // fallback locale
@@ -16,61 +16,67 @@ class Lang {
         'Exception.JKingWeb/Arsse/Lang/Exception.stringInvalid'          => 'Message string "{msgID}" is not a valid ICU message string (language files loaded: {fileList})',
     ];
 
-    static public    $path = BASE."locale".DIRECTORY_SEPARATOR; // path to locale files; this is a public property to facilitate unit testing
-    static protected $requirementsMet = false;                  // whether the Intl extension is loaded
-    static protected $synched = false;                          // whether the wanted locale is actually loaded (lazy loading is used by default)
-    static protected $wanted = self::DEFAULT;                   // the currently requested locale
-    static protected $locale = "";                              // the currently loaded locale
-    static protected $loaded = [];                              // the cascade of loaded locale file names
-    static protected $strings = self::REQUIRED;                 // the loaded locale strings, merged
+    public $path;                               // path to locale files; this is a public property to facilitate unit testing
+    static protected $requirementsMet = false;  // whether the Intl extension is loaded
+    protected $synched = false;                 // whether the wanted locale is actually loaded (lazy loading is used by default)
+    protected $wanted = self::DEFAULT;          // the currently requested locale
+    protected $locale = "";                     // the currently loaded locale
+    protected $loaded = [];                     // the cascade of loaded locale file names
+    protected $strings = self::REQUIRED;        // the loaded locale strings, merged
 
-    protected function __construct() {}
+    function __construct(string $path = BASE."locale".DIRECTORY_SEPARATOR) {
+        $this->path = $path;
+    }
 
-    static public function set(string $locale, bool $immediate = false): string {
+    public function set(string $locale, bool $immediate = false): string {
         // make sure the Intl extension is loaded
-        if(!self::$requirementsMet) self::checkRequirements();
+        if(!static::$requirementsMet) static::checkRequirements();
         // if requesting the same locale as already wanted, just return (but load first if we've requested an immediate load)
-        if($locale==self::$wanted) {
-            if($immediate && !self::$synched) self::load();
+        if($locale==$this->wanted) {
+            if($immediate && !$this->synched) $this->load();
             return $locale;
         }
         // if we've requested a locale other than the null locale, fetch the list of available files and find the closest match e.g. en_ca_somedialect -> en_ca
         if($locale != "") {
-            $list = self::listFiles();
+            $list = $this->listFiles();
             // if the default locale is unavailable, this is (for now) an error
             if(!in_array(self::DEFAULT, $list)) throw new Lang\Exception("defaultFileMissing", self::DEFAULT);
-            self::$wanted = self::match($locale, $list);
+            $this->wanted = $this->match($locale, $list);
         } else {
-            self::$wanted = "";
+            $this->wanted = "";
         }
-        self::$synched = false;
+        $this->synched = false;
         // load right now if asked to, otherwise load later when actually required
-        if($immediate) self::load();
-        return self::$wanted;
+        if($immediate) $this->load();
+        return $this->wanted;
     }
 
-    static public function get(bool $loaded = false): string {
+    public function get(bool $loaded = false): string {
         // we can either return the wanted locale (default) or the currently loaded locale
-        return $loaded ? self::$locale : self::$wanted;
+        return $loaded ? $this->locale : $this->wanted;
+    }
+
+    public function dump(): array {
+        return $this->strings;
     }
 
-    static public function dump(): array {
-        return self::$strings;
+    public function msg(string $msgID, $vars = null): string {
+        return $this($msgID, $vars);
     }
 
-    static public function msg(string $msgID, $vars = null): string {
+    public function __invoke(string $msgID, $vars = null): string {
         // if we're trying to load the system default language and it fails, we have a chicken and egg problem, so we catch the exception and load no language file instead
-        if(!self::$synched) try {self::load();} catch(Lang\Exception $e) {
-            if(self::$wanted==self::DEFAULT) {
-                self::set("", true);
+        if(!$this->synched) try {$this->load();} catch(Lang\Exception $e) {
+            if($this->wanted==self::DEFAULT) {
+                $this->set("", true);
             } else {
                 throw $e;
             }
         }
         // if the requested message is not present in any of the currently loaded language files, throw an exception
         // note that this is indicative of a programming error since the default locale should have all strings
-        if(!array_key_exists($msgID, self::$strings)) throw new Lang\Exception("stringMissing", ['msgID' => $msgID, 'fileList' => implode(", ",self::$loaded)]);
-        $msg = self::$strings[$msgID];
+        if(!array_key_exists($msgID, $this->strings)) throw new Lang\Exception("stringMissing", ['msgID' => $msgID, 'fileList' => implode(", ",$this->loaded)]);
+        $msg = $this->strings[$msgID];
         // variables fed to MessageFormatter must be contained in an array
         if($vars===null) {
             // even though strings not given parameters will not get formatted, we do not optimize this case away: we still want to catch invalid strings
@@ -78,36 +84,36 @@ class Lang {
         } else if(!is_array($vars)) {
             $vars = [$vars];
         }
-        $msg = \MessageFormatter::formatMessage(self::$locale, $msg, $vars);
-        if($msg===false) throw new Lang\Exception("stringInvalid", ['msgID' => $msgID, 'fileList' => implode(", ",self::$loaded)]);
+        $msg = \MessageFormatter::formatMessage($this->locale, $msg, $vars);
+        if($msg===false) throw new Lang\Exception("stringInvalid", ['msgID' => $msgID, 'fileList' => implode(", ",$this->loaded)]);
         return $msg;
     }
 
-    static public function list(string $locale = ""): array {
+    public function list(string $locale = ""): array {
         $out = [];
-        $files = self::listFiles();
+        $files = $this->listFiles();
         foreach($files as $tag) {
             $out[$tag] = \Locale::getDisplayName($tag, ($locale=="") ? $tag : $locale);
         }
         return $out;
     }
 
-    static public function match(string $locale, array $list = null): string {
-        if($list===null) $list = self::listFiles();
-        $default = (self::$locale=="") ? self::DEFAULT : self::$locale;
+    public function match(string $locale, array $list = null): string {
+        if($list===null) $list = $this->listFiles();
+        $default = ($this->locale=="") ? self::DEFAULT : $this->locale;
         return \Locale::lookup($list,$locale, true, $default);
     }
 
     static protected function checkRequirements(): bool {
         if(!extension_loaded("intl")) throw new ExceptionFatal("The \"Intl\" extension is required, but not loaded");
-        self::$requirementsMet = true;
+        static::$requirementsMet = true;
         return true;
     }
 
-    static protected function listFiles(): array {
-        $out = glob(self::$path."*.php");
+    protected function listFiles(): array {
+        $out = glob($this->path."*.php");
         // built-in glob doesn't work with vfsStream (and this other glob doesn't seem to work with Windows paths), so we try both
-        if(empty($out)) $out = Glob::glob(self::$path."*.php"); // FIXME: we should just mock glob() in tests instead and make this a dev dependency
+        if(empty($out)) $out = Glob::glob($this->path."*.php"); // FIXME: we should just mock glob() in tests instead and make this a dev dependency
         // trim the returned file paths to return just the language tag
         $out = array_map(function($file) {
             $file = str_replace(DIRECTORY_SEPARATOR, "/", $file);
@@ -119,17 +125,17 @@ class Lang {
         return $out;
     }
 
-    static protected function load(): bool {
+    protected function load(): bool {
         if(!self::$requirementsMet) self::checkRequirements();
         // if we've requested no locale (""), just load the fallback strings and return
-        if(self::$wanted=="") {
-            self::$strings = self::REQUIRED;
-            self::$locale = self::$wanted;
-            self::$synched = true;
+        if($this->wanted=="") {
+            $this->strings = self::REQUIRED;
+            $this->locale = $this->wanted;
+            $this->synched = true;
             return true;
         }
         // decompose the requested locale from specific to general, building a list of files to load
-        $tags = \Locale::parseLocale(self::$wanted);
+        $tags = \Locale::parseLocale($this->wanted);
         $files = [];
         while(sizeof($tags) > 0) {
             $files[] = strtolower(\Locale::composeLocale($tags));
@@ -142,7 +148,7 @@ class Lang {
         // reduce the list of files to be loaded to the minimum necessary (e.g. if we go from "fr" to "fr_ca", we don't need to load "fr" or "en")
         $files = [];
         foreach($loaded as $file) {
-            if($file==self::$locale) break;
+            if($file==$this->locale) break;
             $files[] = $file;
         }
         // if we need to load all files, start with the fallback strings
@@ -151,17 +157,17 @@ class Lang {
             $strings[] = self::REQUIRED;
         } else {
             // otherwise start with the strings we already have if we're going from e.g. "fr" to "fr_ca"
-            $strings[] = self::$strings;
+            $strings[] = $this->strings;
         }
         // read files in reverse order
         $files = array_reverse($files);
         foreach($files as $file) {
-            if(!file_exists(self::$path."$file.php")) throw new Lang\Exception("fileMissing", $file);
-            if(!is_readable(self::$path."$file.php")) throw new Lang\Exception("fileUnreadable", $file);
+            if(!file_exists($this->path."$file.php")) throw new Lang\Exception("fileMissing", $file);
+            if(!is_readable($this->path."$file.php")) throw new Lang\Exception("fileUnreadable", $file);
             try {
                 // we use output buffering in case the language file is corrupted
                 ob_start();
-                $arr = (include self::$path."$file.php");
+                $arr = (include $this->path."$file.php");
             } catch(\Throwable $e) {
                 $arr = null;
             } finally {
@@ -171,10 +177,10 @@ class Lang {
             $strings[] = $arr;
         }
         // apply the results and return
-        self::$strings = call_user_func_array("array_replace_recursive", $strings);
-        self::$loaded = $loaded;
-        self::$locale = self::$wanted;
-        self::$synched = true;
+        $this->strings = call_user_func_array("array_replace_recursive", $strings);
+        $this->loaded = $loaded;
+        $this->locale = $this->wanted;
+        $this->synched = true;
         return true;
     }
 }
\ No newline at end of file
diff --git a/lib/Lang/Exception.php b/lib/Lang/Exception.php
index 772b695..5340437 100644
--- a/lib/Lang/Exception.php
+++ b/lib/Lang/Exception.php
@@ -3,22 +3,4 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\Lang;
 
 class Exception extends \JKingWeb\Arsse\AbstractException {
-    static $test = false; // used during PHPUnit testing only
-
-    function __construct(string $msgID = "", $vars = null, \Throwable $e = null) {
-        if(!self::$test) {
-            parent::__construct($msgID, $vars, $e);
-        } else {
-            $codeID = "Lang/Exception.$msgID";
-            if(!array_key_exists($codeID,self::CODES)) {
-                $code = -1;
-                $msg = "Exception.".str_replace("\\","/",parent::class).".uncoded";
-                $vars = $msgID;
-            } else {
-                $code = self::CODES[$codeID];
-                $msg = "Exception.".str_replace("\\","/",__CLASS__).".$msgID";
-            }
-            \Exception::__construct($msg, $code, $e);
-        }
-    }
 }
\ No newline at end of file
diff --git a/lib/REST.php b/lib/REST.php
index 964f286..41693cc 100644
--- a/lib/REST.php
+++ b/lib/REST.php
@@ -26,8 +26,7 @@ class REST {
     ];
     protected $data;
     
-    function __construct(RuntimeData $data) {
-        $this->data = $data;
+    function __construct() {
     }
 
     function dispatch(REST\Request $req = null): bool {
@@ -35,7 +34,7 @@ class REST {
         $api = $this->apiMatch($url, $this->apis);
         $req->url = substr($url,strlen($this->apis[$api]['strip']));
         $class = $this->apis[$api]['class'];
-        $drv = new $class($this->data);
+        $drv = new $class();
         $drv->dispatch($req);
         return true;
     }
diff --git a/lib/REST/AbstractHandler.php b/lib/REST/AbstractHandler.php
index ac609d8..d4fa891 100644
--- a/lib/REST/AbstractHandler.php
+++ b/lib/REST/AbstractHandler.php
@@ -3,7 +3,7 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\REST;
 
 abstract class AbstractHandler implements Handler {
-	abstract function __construct(\JKingWeb\Arsse\RuntimeData $data);
+	abstract function __construct();
 	abstract function dispatch(Request $req): Response;
 
 	protected function parseURL(string $url): array {
diff --git a/lib/REST/Handler.php b/lib/REST/Handler.php
index bc86dd6..a07bcd1 100644
--- a/lib/REST/Handler.php
+++ b/lib/REST/Handler.php
@@ -3,6 +3,6 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\REST;
 
 interface Handler {
-    function __construct(\JKingWeb\Arsse\RuntimeData $data);
+    function __construct();
 	function dispatch(Request $req): Response;
 }
\ No newline at end of file
diff --git a/lib/REST/NextCloudNews/Versions.php b/lib/REST/NextCloudNews/Versions.php
index caf0f46..aa923e2 100644
--- a/lib/REST/NextCloudNews/Versions.php
+++ b/lib/REST/NextCloudNews/Versions.php
@@ -4,8 +4,7 @@ namespace JKingWeb\Arsse\REST\NextCloudNews;
 use JKingWeb\Arsse\REST\Response;
 
 class Versions extends \JKingWeb\Arsse\REST\AbstractHandler {
-	function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-		// runtime data is not needed; this method is deliberately empty
+	function __construct() {
 	}
 
 	function dispatch(\JKingWeb\Arsse\REST\Request $req): \JKingWeb\Arsse\REST\Response {
diff --git a/lib/RuntimeData.php b/lib/RuntimeData.php
deleted file mode 100644
index dc594ea..0000000
--- a/lib/RuntimeData.php
+++ /dev/null
@@ -1,16 +0,0 @@
-<?php
-declare(strict_types=1);
-namespace JKingWeb\Arsse;
-
-class RuntimeData {
-    public $conf;
-    public $db;
-    public $user;
-
-    public function __construct(Conf $conf) {
-        $this->conf = $conf;
-        Lang::set($conf->lang);
-        $this->db = new Database($this);
-        $this->user = new User($this);
-    }
-}
\ No newline at end of file
diff --git a/lib/User.php b/lib/User.php
index da0f691..9b9a45a 100644
--- a/lib/User.php
+++ b/lib/User.php
@@ -5,7 +5,6 @@ namespace JKingWeb\Arsse;
 class User {
     public  $id = null;
 
-    protected $data;
     protected $u;
     protected $authz = true;
     protected $authzSupported = 0;
@@ -23,10 +22,9 @@ class User {
         return $classes;
     }
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-        $this->data = $data;
-        $driver = $data->conf->userDriver;
-        $this->u = new $driver($data);
+    public function __construct() {
+        $driver = Data::$conf->userDriver;
+        $this->u = new $driver();
         $this->authzSupported = $this->u->driverFunctions("authorize");
     }
 
@@ -42,9 +40,9 @@ class User {
         // if we don't have a logged-in user, fetch credentials
         if($this->id===null) $this->credentials();
         // if the affected user is the actor and the actor is not trying to grant themselves rights, accept the request
-        if($affectedUser==$this->data->user->id && $action != "userRightsSet") return true;
+        if($affectedUser==Data::$user->id && $action != "userRightsSet") return true;
         // get properties of actor if not already available
-        if(!sizeof($this->actor)) $this->actor = $this->propertiesGet($this->data->user->id);
+        if(!sizeof($this->actor)) $this->actor = $this->propertiesGet(Data::$user->id);
         $rights =& $this->actor["rights"];
         // if actor is a global admin, accept the request
         if($rights==User\Driver::RIGHTS_GLOBAL_ADMIN) return true;
@@ -53,7 +51,7 @@ class User {
         // if actor is not some other sort of admin, deny the request
         if(!in_array($rights,[User\Driver::RIGHTS_GLOBAL_MANAGER,User\Driver::RIGHTS_DOMAIN_MANAGER,User\Driver::RIGHTS_DOMAIN_ADMIN],true)) return false;
         // if actor is a domain admin/manager and domains don't match, deny the request
-        if($this->data->conf->userComposeNames && $this->actor["domain"] && $rights != User\Driver::RIGHTS_GLOBAL_MANAGER) {
+        if(Data::$conf->userComposeNames && $this->actor["domain"] && $rights != User\Driver::RIGHTS_GLOBAL_MANAGER) {
             $test = "@".$this->actor["domain"];
             if(substr($affectedUser,-1*strlen($test)) != $test) return false;
         }
@@ -79,7 +77,7 @@ class User {
     }
     
     public function credentials(): array {
-        if($this->data->conf->userAuthPreferHTTP) {
+        if(Data::$conf->userAuthPreferHTTP) {
             return $this->credentialsHTTP();
         } else {
             return $this->credentialsForm();
@@ -100,7 +98,7 @@ class User {
         } else {
             $out = ["user" => "", "password" => ""];
         }
-        if($this->data->conf->userComposeNames && $out["user"] != "") {
+        if(Data::$conf->userComposeNames && $out["user"] != "") {
             $out["user"] = $this->composeName($out["user"]);
         }
         $this->id = $out["user"];
@@ -109,7 +107,7 @@ class User {
 
     public function auth(string $user = null, string $password = null): bool {
         if($user===null) {
-            if($this->data->conf->userAuthPreferHTTP) return $this->authHTTP();
+            if(Data::$conf->userAuthPreferHTTP) return $this->authHTTP();
             return $this->authForm();
         } else {
             $this->id = $user;
@@ -117,7 +115,7 @@ class User {
             switch($this->u->driverFunctions("auth")) {
                 case User\Driver::FUNC_EXTERNAL:
                     $out = $this->u->auth($user, $password);
-                    if($out && !$this->data->db->userExists($user)) $this->autoProvision($user, $password);
+                    if($out && !Data::$db->userExists($user)) $this->autoProvision($user, $password);
                     return $out;
                 case User\Driver::FUNC_INTERNAL:
                     return $this->u->auth($user, $password);
@@ -176,7 +174,7 @@ class User {
                 // we handle authorization checks for external drivers
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userExists($user);
-                if($out && !$this->data->db->userExists($user)) $this->autoProvision($user, "");
+                if($out && !Data::$db->userExists($user)) $this->autoProvision($user, "");
                 return $out;
             case User\Driver::FUNC_INTERNAL:
                 // internal functions handle their own authorization
@@ -195,7 +193,7 @@ class User {
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $newPassword = $this->u->userAdd($user, $password);
                 // if there was no exception and we don't have the user in the internal database, add it
-                if(!$this->data->db->userExists($user)) $this->autoProvision($user, $newPassword);
+                if(!Data::$db->userExists($user)) $this->autoProvision($user, $newPassword);
                 return $newPassword;
             case User\Driver::FUNC_INTERNAL:
                 // internal functions handle their own authorization
@@ -212,9 +210,9 @@ class User {
                 // we handle authorization checks for external drivers
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userRemove($user);
-                if($out && $this->data->db->userExists($user)) {
+                if($out && Data::$db->userExists($user)) {
                     // if the user was removed and we have it in our data, remove it there
-                    if(!$this->data->db->userExists($user)) $this->data->db->userRemove($user);
+                    if(!Data::$db->userExists($user)) Data::$db->userRemove($user);
                 }
                 return $out;
             case User\Driver::FUNC_INTERNAL:
@@ -232,9 +230,9 @@ class User {
                 // we handle authorization checks for external drivers
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userPasswordSet($user, $newPassword, $oldPassword);
-                if($this->data->db->userExists($user)) {
+                if(Data::$db->userExists($user)) {
                     // if the password change was successful and the user exists, set the internal password to the same value
-                    $this->data->db->userPasswordSet($user, $out);
+                    Data::$db->userPasswordSet($user, $out);
                 } else {
                     // if the user does not exists in the internal database, create it
                     $this->autoProvision($user, $out);
@@ -251,7 +249,7 @@ class User {
     public function propertiesGet(string $user): array {
         // prepare default values
         $domain = null;
-        if($this->data->conf->userComposeNames) $domain = substr($user,strrpos($user,"@")+1);
+        if(Data::$conf->userComposeNames) $domain = substr($user,strrpos($user,"@")+1);
         $init = [
             "id"     => $user,
             "name"   => $user,
@@ -267,7 +265,7 @@ class User {
                 // remove password if it is return (not exhaustive, but...)
                 if(array_key_exists('password', $out)) unset($out['password']);
                 // if the user does not exist in the internal database, add it
-                if(!$this->data->db->userExists($user)) $this->autoProvision($user, "", $out);
+                if(!Data::$db->userExists($user)) $this->autoProvision($user, "", $out);
                 return $out;
             case User\Driver::FUNC_INTERNAL:
                 // internal functions handle their own authorization
@@ -289,9 +287,9 @@ class User {
                 // we handle authorization checks for external drivers
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userPropertiesSet($user, $properties);
-                if($this->data->db->userExists($user)) {
+                if(Data::$db->userExists($user)) {
                     // if the property change was successful and the user exists, set the internal properties to the same values
-                    $this->data->db->userPropertiesSet($user, $out);
+                    Data::$db->userPropertiesSet($user, $out);
                 } else {
                     // if the user does not exists in the internal database, create it
                     $this->autoProvision($user, "", $out);
@@ -313,7 +311,7 @@ class User {
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userRightsGet($user);
                 // if the user does not exist in the internal database, add it
-                if(!$this->data->db->userExists($user)) $this->autoProvision($user, "", null, $out);
+                if(!Data::$db->userExists($user)) $this->autoProvision($user, "", null, $out);
                 return $out;
             case User\Driver::FUNC_INTERNAL:
                 // internal functions handle their own authorization
@@ -332,10 +330,10 @@ class User {
                 if(!$this->authorize($user, $func)) throw new User\ExceptionAuthz("notAuthorized", ["action" => $func, "user" => $user]);
                 $out = $this->u->userRightsSet($user, $level);
                 // if the user does not exist in the internal database, add it
-                if($out && $this->data->db->userExists($user)) {
+                if($out && Data::$db->userExists($user)) {
                     $authz = $this->authorizationEnabled();
                     $this->authorizationEnabled(false);
-                    $this->data->db->userRightsSet($user, $level);
+                    Data::$db->userRightsSet($user, $level);
                     $this->authorizationEnabled($authz);
                 } else if($out) {
                     $this->autoProvision($user, "", null, $level);
@@ -367,18 +365,18 @@ class User {
         $authz = $this->authorizationEnabled();
         $this->authorizationEnabled(false);
         // create the user
-        $out = $this->data->db->userAdd($user, $password);
+        $out = Data::$db->userAdd($user, $password);
         // set the user rights
-        $this->data->db->userRightsSet($user, $rights);
+        Data::$db->userRightsSet($user, $rights);
         // set the user properties...
         if($properties===null) {
             // if nothing is provided but the driver uses an external function, try to get the current values from the external source
             try {
-                if($this->u->driverFunctions("userPropertiesGet")==User\Driver::FUNC_EXTERNAL) $this->data->db->userPropertiesSet($user, $this->u->userPropertiesGet($user));
+                if($this->u->driverFunctions("userPropertiesGet")==User\Driver::FUNC_EXTERNAL) Data::$db->userPropertiesSet($user, $this->u->userPropertiesGet($user));
             } catch(\Throwable $e) {}
         } else {
             // otherwise if values are provided, use those
-            $this->data->db->userPropertiesSet($user, $properties);
+            Data::$db->userPropertiesSet($user, $properties);
         }
         // re-enable authorization and return
         $this->authorizationEnabled($authz);
diff --git a/lib/User/Driver.php b/lib/User/Driver.php
index 4df2d16..b842827 100644
--- a/lib/User/Driver.php
+++ b/lib/User/Driver.php
@@ -13,8 +13,8 @@ Interface Driver {
     const RIGHTS_GLOBAL_MANAGER = 75;   // able to act for any normal users on any domain; cannot elevate other users
     const RIGHTS_GLOBAL_ADMIN   = 100;  // is completely unrestricted
 
-    // returns an instance of a class implementing this interface. Implemented as a static method for consistency with database classes
-    function __construct(\JKingWeb\Arsse\RuntimeData $data);
+    // returns an instance of a class implementing this interface.
+    function __construct();
     // returns a human-friendly name for the driver (for display in installer, for example)
     static function driverName(): string;
     // returns an array (or single queried member of same) of methods defined by this interface and whether the class implements the internal function or a custom version
diff --git a/lib/User/Internal/Driver.php b/lib/User/Internal/Driver.php
index 93d56a8..62b4f76 100644
--- a/lib/User/Internal/Driver.php
+++ b/lib/User/Internal/Driver.php
@@ -1,13 +1,11 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\User\Internal;
-use JKingWeb\Arsse\Lang;
 use JKingWeb\Arsse\User\Driver as Iface;
 
 final class Driver implements Iface {
     use InternalFunctions;
 
-    protected $data;
     protected $db;
     protected $functions = [
         "auth"                    => Iface::FUNC_INTERNAL,
@@ -22,12 +20,8 @@ final class Driver implements Iface {
         "userRightsSet"           => Iface::FUNC_INTERNAL,
     ];
 
-    static public function create(\JKingWeb\Arsse\RuntimeData $data): Driver {
-        return new static($data);
-    }
-
     static public function driverName(): string {
-        return Lang::msg("Driver.User.Internal.Name");
+        return Data::$l->msg("Driver.User.Internal.Name");
     }
 
     public function driverFunctions(string $function = null) {
diff --git a/lib/User/Internal/InternalFunctions.php b/lib/User/Internal/InternalFunctions.php
index 6a3693a..ef5f2ee 100644
--- a/lib/User/Internal/InternalFunctions.php
+++ b/lib/User/Internal/InternalFunctions.php
@@ -1,17 +1,17 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\User\Internal;
+use JKingWeb\Arsse\Data;
 
 trait InternalFunctions {    
     protected $actor = [];
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-        $this->data = $data;
-        $this->db = $this->data->db;
+    public function __construct() {
+        $this->db = Data::$db;
     }
 
     function auth(string $user, string $password): bool {
-        if(!$this->data->user->exists($user)) return false;
+        if(!Data::$user->exists($user)) return false;
         $hash = $this->db->userPasswordGet($user);
         if($password==="" && $hash==="") return true;
         return password_verify($password, $hash);
diff --git a/tests/Conf/TestConf.php b/tests/Conf/TestConf.php
index 70fffa3..aafd35b 100644
--- a/tests/Conf/TestConf.php
+++ b/tests/Conf/TestConf.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \org\bovigo\vfs\vfsStream;
+use org\bovigo\vfs\vfsStream;
 
 
 class TestConf extends \PHPUnit\Framework\TestCase {
@@ -10,7 +10,8 @@ class TestConf extends \PHPUnit\Framework\TestCase {
     static $vfs;
     static $path;
 
-    static function setUpBeforeClass() {
+    function setUp() {
+        $this->clearData();
         self::$vfs = vfsStream::setup("root", null, [
             'confGood'       => '<?php return Array("lang" => "xx");',
             'confNotArray'   => '<?php return 0;',
@@ -24,9 +25,10 @@ class TestConf extends \PHPUnit\Framework\TestCase {
         chmod(self::$path."confUnreadable", 0000);
     }
 
-    static function tearDownAfterClass() {
+    function tearDown() {
         self::$path = null;
         self::$vfs = null;
+        $this->clearData();
     }
     
     function testLoadDefaultValues() {
diff --git a/tests/Db/SQLite3/TestDbDriverSQLite3.php b/tests/Db/SQLite3/TestDbDriverSQLite3.php
index c787b3e..0e0300c 100644
--- a/tests/Db/SQLite3/TestDbDriverSQLite3.php
+++ b/tests/Db/SQLite3/TestDbDriverSQLite3.php
@@ -10,20 +10,22 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	protected $drv;
 
     function setUp() {
+		$this->clearData();
 		$conf = new Conf();
 		$conf->dbDriver = Db\SQLite3\Driver::class;
 		$conf->dbSQLite3File = tempnam(sys_get_temp_dir(), 'ook');
-		$this->data = new Test\RuntimeData($conf);
-		$this->drv = new Db\SQLite3\Driver($this->data, true);
+		Data::$conf = $conf;
+		$this->drv = new Db\SQLite3\Driver(true);
     }
 
     function tearDown() {
         unset($this->drv);
-		unlink($this->data->conf->dbSQLite3File);
+		unlink(Data::$conf->dbSQLite3File);
+		$this->clearData();
     }
 
 	function testFetchDriverName() {
-		$class = $this->data->conf->dbDriver;
+		$class = Data::$conf->dbDriver;
 		$this->assertTrue(strlen($class::driverName()) > 0);
 	}
 	
@@ -38,12 +40,12 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 
 	function testExecMultipleStatements() {
 		$this->assertTrue($this->drv->exec("CREATE TABLE test(id integer primary key); INSERT INTO test(id) values(2112)"));
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->assertEquals(2112, $ch->querySingle("SELECT id from test"));
 	}
 
 	function testExecTimeout() {
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$ch->exec("BEGIN EXCLUSIVE TRANSACTION");
 		$this->assertException("general", "Db", "ExceptionTimeout");
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
@@ -71,7 +73,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	}
 
 	function testQueryTimeout() {
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$ch->exec("BEGIN EXCLUSIVE TRANSACTION");
 		$this->assertException("general", "Db", "ExceptionTimeout");
 		$this->drv->query("CREATE TABLE test(id integer primary key)");
@@ -102,7 +104,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testBeginTransaction() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -116,7 +118,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testCommitTransaction() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -130,7 +132,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testRollbackTransaction() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -144,7 +146,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testBeginChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -159,7 +161,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testCommitChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -178,7 +180,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testRollbackChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -199,7 +201,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testPartiallyRollbackChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -220,7 +222,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testFullyRollbackChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
@@ -238,7 +240,7 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
 	function testFullyCommitChainedTransactions() {
 		$select = "SELECT count(*) FROM test";
 		$insert = "INSERT INTO test(id) values(null)";
-		$ch = new \SQLite3($this->data->conf->dbSQLite3File);
+		$ch = new \SQLite3(Data::$conf->dbSQLite3File);
 		$this->drv->exec("CREATE TABLE test(id integer primary key)");
 		$this->drv->begin();
 		$this->drv->query($insert);
diff --git a/tests/Db/SQLite3/TestDbUpdateSQLite3.php b/tests/Db/SQLite3/TestDbUpdateSQLite3.php
index 54af669..8400675 100644
--- a/tests/Db/SQLite3/TestDbUpdateSQLite3.php
+++ b/tests/Db/SQLite3/TestDbUpdateSQLite3.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \org\bovigo\vfs\vfsStream;
+use org\bovigo\vfs\vfsStream;
 
 
 class TestDbUpdateSQLite3 extends \PHPUnit\Framework\TestCase {
@@ -16,20 +16,22 @@ class TestDbUpdateSQLite3 extends \PHPUnit\Framework\TestCase {
 	const MINIMAL2 = "pragma user_version=2";
 
     function setUp() {
+		$this->clearData();
         $this->vfs = vfsStream::setup("schemata", null, ['SQLite3' => []]);
 		$conf = new Conf();
 		$conf->dbDriver = Db\SQLite3\Driver::class;
 		$conf->dbSchemaBase = $this->vfs->url();
 		$this->base = $this->vfs->url()."/SQLite3/";
 		$conf->dbSQLite3File = ":memory:";
-		$this->data = new Test\RuntimeData($conf);
-		$this->drv = new Db\SQLite3\Driver($this->data, true);
+		Data::$conf = $conf;
+		$this->drv = new Db\SQLite3\Driver(true);
     }
 
     function tearDown() {
         unset($this->drv);
         unset($this->data);
         unset($this->vfs);
+		$this->clearData();
     }
 
 	function testLoadMissingFile() {
@@ -82,7 +84,7 @@ class TestDbUpdateSQLite3 extends \PHPUnit\Framework\TestCase {
 	}
 
 	function testPerformActualUpdate() {
-	    $this->data->conf->dbSchemaBase = (new Conf())->dbSchemaBase;
+	    Data::$conf->dbSchemaBase = (new Conf())->dbSchemaBase;
 		$this->drv->schemaUpdate(Database::SCHEMA_VERSION);
 		$this->assertEquals(Database::SCHEMA_VERSION, $this->drv->schemaVersion());
 	}
diff --git a/tests/Exception/TestException.php b/tests/Exception/TestException.php
index 0352f2d..12baeee 100644
--- a/tests/Exception/TestException.php
+++ b/tests/Exception/TestException.php
@@ -6,12 +6,15 @@ namespace JKingWeb\Arsse;
 class TestException extends \PHPUnit\Framework\TestCase {
     use Test\Tools;
 
-    static function setUpBeforeClass() {
-        Lang::set("");
+    function setUp() {
+        $this->clearData(false);
+        $m = $this->getMockBuilder(Lang::class)->setMethods(['__invoke'])->getMock();
+        $m->expects($this->any())->method("__invoke")->with($this->anything(), $this->anything())->will($this->returnValue(""));
+        Data::$l = $m;
     }
 
-    static function tearDownAfterClass() {
-        Lang::set(Lang::DEFAULT);
+    function tearDown() {
+        $this->clearData(true);
     }
     
     function testBaseClass() {
@@ -51,14 +54,6 @@ class TestException extends \PHPUnit\Framework\TestCase {
         throw new Exception("testThisExceptionMessageDoesNotExist");
     }
 
-    /**
-     * @depends testBaseClass
-     */
-    function testBaseClassWithMissingMessage() {
-        $this->assertException("stringMissing", "Lang");
-        throw new Exception("invalid");
-    }
-
     /**
      * @depends testBaseClassWithUnknownCode
      */
@@ -66,5 +61,4 @@ class TestException extends \PHPUnit\Framework\TestCase {
         $this->assertException("uncoded");
         throw new Lang\Exception("testThisExceptionMessageDoesNotExist");
     }
-    
 }
diff --git a/tests/Lang/TestLang.php b/tests/Lang/TestLang.php
index e5711ba..54b94a8 100644
--- a/tests/Lang/TestLang.php
+++ b/tests/Lang/TestLang.php
@@ -1,48 +1,47 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \org\bovigo\vfs\vfsStream;
+use org\bovigo\vfs\vfsStream;
 
 
 class TestLang extends \PHPUnit\Framework\TestCase {
     use Test\Tools, Test\Lang\Setup;
 
-    static $vfs;
-    static $path;
-    static $files;
-    static $defaultPath;
+    public $files;
+    public $path;
+    public $l;
 
     function testListLanguages() {
-        $this->assertCount(sizeof(self::$files), Lang::list("en"));
+        $this->assertCount(sizeof($this->files), $this->l->list("en"));
     }
 
     /**
      * @depends testListLanguages
      */
     function testSetLanguage() {
-        $this->assertEquals("en", Lang::set("en"));
-        $this->assertEquals("en_ca", Lang::set("en_ca"));
-        $this->assertEquals("de", Lang::set("de_ch"));
-        $this->assertEquals("en", Lang::set("en_gb_hixie"));
-        $this->assertEquals("en_ca", Lang::set("en_ca_jking"));
-        $this->assertEquals("en", Lang::set("es"));
-        $this->assertEquals("", Lang::set(""));
+        $this->assertEquals("en", $this->l->set("en"));
+        $this->assertEquals("en_ca", $this->l->set("en_ca"));
+        $this->assertEquals("de", $this->l->set("de_ch"));
+        $this->assertEquals("en", $this->l->set("en_gb_hixie"));
+        $this->assertEquals("en_ca", $this->l->set("en_ca_jking"));
+        $this->assertEquals("en", $this->l->set("es"));
+        $this->assertEquals("", $this->l->set(""));
     }
 
     /**
      * @depends testSetLanguage
      */
     function testLoadInternalStrings() {
-        $this->assertEquals("", Lang::set("", true));
-        $this->assertCount(sizeof(Lang::REQUIRED), Lang::dump());
+        $this->assertEquals("", $this->l->set("", true));
+        $this->assertCount(sizeof(Lang::REQUIRED), $this->l->dump());
     }
 
     /**
      * @depends testLoadInternalStrings
      */
     function testLoadDefaultLanguage() {
-        $this->assertEquals(Lang::DEFAULT, Lang::set(Lang::DEFAULT, true));
-        $str = Lang::dump();
+        $this->assertEquals(Lang::DEFAULT, $this->l->set(Lang::DEFAULT, true));
+        $str = $this->l->dump();
         $this->assertArrayHasKey('Exception.JKingWeb/Arsse/Exception.uncoded', $str);
         $this->assertArrayHasKey('Test.presentText', $str);
     }
@@ -51,9 +50,9 @@ class TestLang extends \PHPUnit\Framework\TestCase {
      * @depends testLoadDefaultLanguage
      */
     function testLoadSupplementaryLanguage() {
-        Lang::set(Lang::DEFAULT, true);
-        $this->assertEquals("ja", Lang::set("ja", true));
-        $str = Lang::dump();
+        $this->l->set(Lang::DEFAULT, true);
+        $this->assertEquals("ja", $this->l->set("ja", true));
+        $str = $this->l->dump();
         $this->assertArrayHasKey('Exception.JKingWeb/Arsse/Exception.uncoded', $str);
         $this->assertArrayHasKey('Test.presentText', $str);
         $this->assertArrayHasKey('Test.absentText', $str);
diff --git a/tests/Lang/TestLangErrors.php b/tests/Lang/TestLangErrors.php
index 7875a0c..6a09685 100644
--- a/tests/Lang/TestLangErrors.php
+++ b/tests/Lang/TestLangErrors.php
@@ -1,66 +1,64 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \org\bovigo\vfs\vfsStream;
+use org\bovigo\vfs\vfsStream;
 
 
 class TestLangErrors extends \PHPUnit\Framework\TestCase {
     use Test\Tools, Test\Lang\Setup;
 
-    static $vfs;
-    static $path;
-    static $files;
-    static $defaultPath;
+    public $files;
+    public $path;
+    public $l;
 
-    function setUp() {
-        Lang::set("", true);
+    function setUpSeries() {
+        $this->l->set("", true);
     }
 
     function testLoadEmptyFile() {
         $this->assertException("fileCorrupt", "Lang");
-        Lang::set("fr_ca", true);
+        $this->l->set("fr_ca", true);
     }
 
     function testLoadFileWhichDoesNotReturnAnArray() {
         $this->assertException("fileCorrupt", "Lang");
-        Lang::set("it", true);
+        $this->l->set("it", true);
     }
 
     function testLoadFileWhichIsNotPhp() {
         $this->assertException("fileCorrupt", "Lang");
-        Lang::set("ko", true);
+        $this->l->set("ko", true);
     }
 
     function testLoadFileWhichIsCorrupt() {
         $this->assertException("fileCorrupt", "Lang");
-        Lang::set("zh", true);
+        $this->l->set("zh", true);
     }
 
     function testLoadFileWithooutReadPermission() {
         $this->assertException("fileUnreadable", "Lang");
-        Lang::set("ru", true);
+        $this->l->set("ru", true);
     }
 
     function testLoadSubtagOfMissingLanguage() {
         $this->assertException("fileMissing", "Lang");
-        Lang::set("pt_br", true);
+        $this->l->set("pt_br", true);
     }
 
     function testFetchInvalidMessage() {
         $this->assertException("stringInvalid", "Lang");
-        Lang::set("vi", true);
-        $txt = Lang::msg('Test.presentText');
+        $this->l->set("vi", true);
+        $txt = $this->l->msg('Test.presentText');
     }
 
     function testFetchMissingMessage() {
         $this->assertException("stringMissing", "Lang");
-        $txt = Lang::msg('Test.absentText');
+        $txt = $this->l->msg('Test.absentText');
     }
 
     function testLoadMissingDefaultLanguage() {
-        // this should be the last test of the series
-        unlink(self::$path.Lang::DEFAULT.".php");
+        unlink($this->path.Lang::DEFAULT.".php");
         $this->assertException("defaultFileMissing", "Lang");
-        Lang::set("fr", true);
+        $this->l->set("fr", true);
     }
 }
\ No newline at end of file
diff --git a/tests/Lang/testLangComplex.php b/tests/Lang/testLangComplex.php
index 000f2e3..72ab416 100644
--- a/tests/Lang/testLangComplex.php
+++ b/tests/Lang/testLangComplex.php
@@ -1,40 +1,39 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse;
-use \org\bovigo\vfs\vfsStream;
+use org\bovigo\vfs\vfsStream;
 
 
 class TestLangComplex extends \PHPUnit\Framework\TestCase {
     use Test\Tools, Test\Lang\Setup;
 
-    static $vfs;
-    static $path;
-    static $files;
-    static $defaultPath;
+    public $files;
+    public $path;
+    public $l;
 
-    function setUp() {
-        Lang::set(Lang::DEFAULT, true);
+    function setUpSeries() {
+        $this->l->set(Lang::DEFAULT, true);
     }
 
     function testLazyLoad() {
-        Lang::set("ja");
-        $this->assertArrayNotHasKey('Test.absentText', Lang::dump());
+        $this->l->set("ja");
+        $this->assertArrayNotHasKey('Test.absentText', $this->l->dump());
     }
     
     /**
      * @depends testLazyLoad
      */
     function testGetWantedAndLoadedLocale() {
-        Lang::set("en", true);
-        Lang::set("ja");
-        $this->assertEquals("ja", Lang::get());
-        $this->assertEquals("en", Lang::get(true));
+        $this->l->set("en", true);
+        $this->l->set("ja");
+        $this->assertEquals("ja", $this->l->get());
+        $this->assertEquals("en", $this->l->get(true));
     }
     
     function testLoadCascadeOfFiles() {
-        Lang::set("ja", true);
-        $this->assertEquals("de", Lang::set("de", true));
-        $str = Lang::dump();
+        $this->l->set("ja", true);
+        $this->assertEquals("de", $this->l->set("de", true));
+        $str = $this->l->dump();
         $this->assertArrayNotHasKey('Test.absentText', $str);
         $this->assertEquals('und der Stein der Weisen', $str['Test.presentText']);
     }
@@ -43,62 +42,62 @@ class TestLangComplex extends \PHPUnit\Framework\TestCase {
      * @depends testLoadCascadeOfFiles
      */
     function testLoadSubtag() {
-        $this->assertEquals("en_ca", Lang::set("en_ca", true));
+        $this->assertEquals("en_ca", $this->l->set("en_ca", true));
     }
     
     function testFetchAMessage() {
-        Lang::set("de", true);
-        $this->assertEquals('und der Stein der Weisen', Lang::msg('Test.presentText'));
+        $this->l->set("de", true);
+        $this->assertEquals('und der Stein der Weisen', $this->l->msg('Test.presentText'));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testFetchAMessageWithMissingParameters() {
-        Lang::set("en_ca", true);
-        $this->assertEquals('{0} and {1}', Lang::msg('Test.presentText'));
+        $this->l->set("en_ca", true);
+        $this->assertEquals('{0} and {1}', $this->l->msg('Test.presentText'));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testFetchAMessageWithSingleNumericParameter() {
-        Lang::set("en_ca", true);
-        $this->assertEquals('Default language file "en" missing', Lang::msg('Exception.JKingWeb/Arsse/Lang/Exception.defaultFileMissing', Lang::DEFAULT));
+        $this->l->set("en_ca", true);
+        $this->assertEquals('Default language file "en" missing', $this->l->msg('Exception.JKingWeb/Arsse/Lang/Exception.defaultFileMissing', Lang::DEFAULT));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testFetchAMessageWithMultipleNumericParameters() {
-        Lang::set("en_ca", true);
-        $this->assertEquals('Happy Rotter and the Philosopher\'s Stone', Lang::msg('Test.presentText', ['Happy Rotter', 'the Philosopher\'s Stone']));
+        $this->l->set("en_ca", true);
+        $this->assertEquals('Happy Rotter and the Philosopher\'s Stone', $this->l->msg('Test.presentText', ['Happy Rotter', 'the Philosopher\'s Stone']));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testFetchAMessageWithNamedParameters() {
-        $this->assertEquals('Message string "Test.absentText" missing from all loaded language files (en)', Lang::msg('Exception.JKingWeb/Arsse/Lang/Exception.stringMissing', ['msgID' => 'Test.absentText', 'fileList' => 'en']));
+        $this->assertEquals('Message string "Test.absentText" missing from all loaded language files (en)', $this->l->msg('Exception.JKingWeb/Arsse/Lang/Exception.stringMissing', ['msgID' => 'Test.absentText', 'fileList' => 'en']));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testReloadDefaultStrings() {
-        Lang::set("de", true);
-        Lang::set("en", true);
-        $this->assertEquals('and the Philosopher\'s Stone', Lang::msg('Test.presentText'));
+        $this->l->set("de", true);
+        $this->l->set("en", true);
+        $this->assertEquals('and the Philosopher\'s Stone', $this->l->msg('Test.presentText'));
     }
 
     /**
      * @depends testFetchAMessage
      */
     function testReloadGeneralTagAfterSubtag() {
-        Lang::set("en", true);
-        Lang::set("en_us", true);
-        $this->assertEquals('and the Sorcerer\'s Stone', Lang::msg('Test.presentText'));
-        Lang::set("en", true);
-        $this->assertEquals('and the Philosopher\'s Stone', Lang::msg('Test.presentText'));
+        $this->l->set("en", true);
+        $this->l->set("en_us", true);
+        $this->assertEquals('and the Sorcerer\'s Stone', $this->l->msg('Test.presentText'));
+        $this->l->set("en", true);
+        $this->assertEquals('and the Philosopher\'s Stone', $this->l->msg('Test.presentText'));
     }
 }
\ No newline at end of file
diff --git a/tests/REST/NextCloudNews/TestNCNVersionDiscovery.php b/tests/REST/NextCloudNews/TestNCNVersionDiscovery.php
index 7be6f64..f44b67e 100644
--- a/tests/REST/NextCloudNews/TestNCNVersionDiscovery.php
+++ b/tests/REST/NextCloudNews/TestNCNVersionDiscovery.php
@@ -9,13 +9,12 @@ class TestNCNVersionDiscovery extends \PHPUnit\Framework\TestCase {
     use Test\Tools;
 
 	function setUp() {
-		$conf = new Conf();
-		$this->data = new Test\RuntimeData($conf);
+		$this->clearData();
 	}
 
 	function testFetchVersionList() {
 		$exp = new Response(200, ['apiLevels' => ['v1-2']]);
-		$h = new Rest\NextCloudNews\Versions($this->data);
+		$h = new Rest\NextCloudNews\Versions();
 		$req = new Request("GET", "/");
 		$res = $h->dispatch($req);
 		$this->assertEquals($exp, $res);
@@ -29,7 +28,7 @@ class TestNCNVersionDiscovery extends \PHPUnit\Framework\TestCase {
 
 	function testUseIncorrectMethod() {
 		$exp = new Response(405);
-		$h = new Rest\NextCloudNews\Versions($this->data);
+		$h = new Rest\NextCloudNews\Versions();
 		$req = new Request("POST", "/");
 		$res = $h->dispatch($req);
 		$this->assertEquals($exp, $res);
@@ -37,7 +36,7 @@ class TestNCNVersionDiscovery extends \PHPUnit\Framework\TestCase {
 
 	function testUseIncorrectPath() {
 		$exp = new Response(404);
-		$h = new Rest\NextCloudNews\Versions($this->data);
+		$h = new Rest\NextCloudNews\Versions();
 		$req = new Request("GET", "/ook");
 		$res = $h->dispatch($req);
 		$this->assertEquals($exp, $res);
diff --git a/tests/User/TestAuthorization.php b/tests/User/TestAuthorization.php
index 60e0b1c..e1870a3 100644
--- a/tests/User/TestAuthorization.php
+++ b/tests/User/TestAuthorization.php
@@ -46,53 +46,58 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 	protected $data;
 
     function setUp(string $drv = Test\User\DriverInternalMock::class, string $db = null) {
+		$this->clearData();
 		$conf = new Conf();
 		$conf->userDriver = $drv;
 		$conf->userAuthPreferHTTP = true;
 		$conf->userComposeNames = true;
-		$this->data = new Test\RuntimeData($conf);
+		Data::$conf = $conf;
 		if($db !== null) {
-			$this->data->db = new $db($this->data);
+			Data::$db = new $db();
 		}
-		$this->data->user = new User($this->data);
-		$this->data->user->authorizationEnabled(false);
+		Data::$user = new User();
+		Data::$user->authorizationEnabled(false);
 		foreach(self::USERS as $user => $level) {
-			$this->data->user->add($user, "");
-			$this->data->user->rightsSet($user, $level);
+			Data::$user->add($user, "");
+			Data::$user->rightsSet($user, $level);
 		}
-		$this->data->user->authorizationEnabled(true);
+		Data::$user->authorizationEnabled(true);
+	}
+
+	function tearDown() {
+		$this->clearData();
 	}
 
 	function testSelfActionLogic() {
 		foreach(array_keys(self::USERS) as $user) {
-			$this->data->user->auth($user, "");
+			Data::$user->auth($user, "");
 			// users should be able to do basic actions for themselves
-			$this->assertTrue($this->data->user->authorize($user, "userExists"), "User $user could not act for themselves.");
-			$this->assertTrue($this->data->user->authorize($user, "userRemove"), "User $user could not act for themselves.");
+			$this->assertTrue(Data::$user->authorize($user, "userExists"), "User $user could not act for themselves.");
+			$this->assertTrue(Data::$user->authorize($user, "userRemove"), "User $user could not act for themselves.");
 		}
 	}
 
 	function testRegularUserLogic() {
 		foreach(self::USERS as $actor => $rights) {
 			if($rights != User\Driver::RIGHTS_NONE) continue;
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			foreach(array_keys(self::USERS) as $affected) {
 				// regular users should only be able to act for themselves
 				if($actor==$affected) {
-					$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
-					$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
-					$this->assertFalse($this->data->user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// they should never be able to set rights
 				foreach(self::LEVELS as $level) {
-					$this->assertFalse($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
 				}
 			}
 			// they should not be able to list users
 			foreach(self::DOMAINS as $domain) {
-				$this->assertFalse($this->data->user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
+				$this->assertFalse(Data::$user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
 			}
 		}
 	}
@@ -101,36 +106,36 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 		foreach(self::USERS as $actor => $actorRights) {
 			if($actorRights != User\Driver::RIGHTS_DOMAIN_MANAGER) continue;
 			$actorDomain = substr($actor,strrpos($actor,"@")+1);
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			foreach(self::USERS as $affected => $affectedRights) {
 				$affectedDomain = substr($affected,strrpos($affected,"@")+1);
 				// domain managers should be able to check any user on the same domain
 				if($actorDomain==$affectedDomain) {
-					$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// they should only be able to act for regular users on the same domain
 				if($actor==$affected || ($actorDomain==$affectedDomain && $affectedRights==User\Driver::RIGHTS_NONE)) {
-					$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// and they should only be able to set their own rights to regular user
 				foreach(self::LEVELS as $level) {
 					if($actor==$affected && in_array($level, [User\Driver::RIGHTS_NONE, User\Driver::RIGHTS_DOMAIN_MANAGER])) {
-						$this->assertTrue($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
+						$this->assertTrue(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
 					} else {
-						$this->assertFalse($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
+						$this->assertFalse(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
 					}
 				}
 			}
 			// they should also be able to list all users on their own domain
 			foreach(self::DOMAINS as $domain) {
 				if($domain=="@".$actorDomain) {
-					$this->assertTrue($this->data->user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
 				}
 			}
 		}
@@ -140,37 +145,37 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 		foreach(self::USERS as $actor => $actorRights) {
 			if($actorRights != User\Driver::RIGHTS_DOMAIN_ADMIN) continue;
 			$actorDomain = substr($actor,strrpos($actor,"@")+1);
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			$allowed = [User\Driver::RIGHTS_NONE,User\Driver::RIGHTS_DOMAIN_MANAGER,User\Driver::RIGHTS_DOMAIN_ADMIN];
 			foreach(self::USERS as $affected => $affectedRights) {
 				$affectedDomain = substr($affected,strrpos($affected,"@")+1);
 				// domain admins should be able to check any user on the same domain
 				if($actorDomain==$affectedDomain) {
-					$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// they should be able to act for any user on the same domain who is not a global manager or admin
 				if($actorDomain==$affectedDomain && in_array($affectedRights, $allowed)) {
-					$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// they should be able to set rights for any user on their domain who is not a global manager or admin, up to domain admin level
 				foreach(self::LEVELS as $level) {
 					if($actorDomain==$affectedDomain && in_array($affectedRights, $allowed) && in_array($level, $allowed)) {
-						$this->assertTrue($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
+						$this->assertTrue(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
 					} else {
-						$this->assertFalse($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
+						$this->assertFalse(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
 					}
 				}
 			}
 			// they should also be able to list all users on their own domain
 			foreach(self::DOMAINS as $domain) {
 				if($domain=="@".$actorDomain) {
-					$this->assertTrue($this->data->user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
 				}
 			}
 		}
@@ -180,29 +185,29 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 		foreach(self::USERS as $actor => $actorRights) {
 			if($actorRights != User\Driver::RIGHTS_GLOBAL_MANAGER) continue;
 			$actorDomain = substr($actor,strrpos($actor,"@")+1);
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			foreach(self::USERS as $affected => $affectedRights) {
 				$affectedDomain = substr($affected,strrpos($affected,"@")+1);
 				// global managers should be able to check any user 
-				$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+				$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
 				// they should only be able to act for regular users
 				if($actor==$affected || $affectedRights==User\Driver::RIGHTS_NONE) {
-					$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// and they should only be able to set their own rights to regular user
 				foreach(self::LEVELS as $level) {
 					if($actor==$affected && in_array($level, [User\Driver::RIGHTS_NONE, User\Driver::RIGHTS_GLOBAL_MANAGER])) {
-						$this->assertTrue($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
+						$this->assertTrue(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
 					} else {
-						$this->assertFalse($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
+						$this->assertFalse(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
 					}
 				}
 			}
 			// they should also be able to list all users
 			foreach(self::DOMAINS as $domain) {
-				$this->assertTrue($this->data->user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
+				$this->assertTrue(Data::$user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
 			}
 		}
 	}
@@ -210,17 +215,17 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 	function testGlobalAdministratorLogic() {
 		foreach(self::USERS as $actor => $actorRights) {
 			if($actorRights != User\Driver::RIGHTS_GLOBAL_ADMIN) continue;
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			// global admins can do anything
 			foreach(self::USERS as $affected => $affectedRights) {
-				$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
-				$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+				$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+				$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				foreach(self::LEVELS as $level) {
-					$this->assertTrue($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted properly for $affected settings rights level $level, but the action was denied.");
 				}
 			}
 			foreach(self::DOMAINS as $domain) {
-				$this->assertTrue($this->data->user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
+				$this->assertTrue(Data::$user->authorize($domain, "userList"), "User $actor properly checked user list for domain '$domain', but the action was denied.");
 			}
 		}
 	}
@@ -228,24 +233,24 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 	function testInvalidLevelLogic() {
 		foreach(self::USERS as $actor => $rights) {
 			if(in_array($rights, self::LEVELS)) continue;
-			$this->data->user->auth($actor, "");
+			Data::$user->auth($actor, "");
 			foreach(array_keys(self::USERS) as $affected) {
 				// users with unknown/invalid rights should be treated just like regular users and only be able to act for themselves
 				if($actor==$affected) {
-					$this->assertTrue($this->data->user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
-					$this->assertTrue($this->data->user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userExists"), "User $actor acted properly for $affected, but the action was denied.");
+					$this->assertTrue(Data::$user->authorize($affected, "userRemove"), "User $actor acted properly for $affected, but the action was denied.");
 				} else {
-					$this->assertFalse($this->data->user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
-					$this->assertFalse($this->data->user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userExists"), "User $actor acted improperly for $affected, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRemove"), "User $actor acted improperly for $affected, but the action was allowed.");
 				}
 				// they should never be able to set rights
 				foreach(self::LEVELS as $level) {
-					$this->assertFalse($this->data->user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
+					$this->assertFalse(Data::$user->authorize($affected, "userRightsSet", $level), "User $actor acted improperly for $affected settings rights level $level, but the action was allowed.");
 				}
 			}
 			// they should not be able to list users
 			foreach(self::DOMAINS as $domain) {
-				$this->assertFalse($this->data->user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
+				$this->assertFalse(Data::$user->authorize($domain, "userList"), "User $actor improperly checked user list for domain '$domain', but the action was allowed.");
 			}
 		}
 	}
@@ -264,10 +269,10 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 			'list'          => [],
 		];
 		// try first with a global admin (there should be no exception)
-		$this->data->user->auth("gadm@example.com", "");
+		Data::$user->auth("gadm@example.com", "");
 		$this->assertCount(0, $this->checkExceptions("user@example.org", $tests));
 		// next try with a regular user acting on another user (everything should fail)
-		$this->data->user->auth("user@example.com", "");
+		Data::$user->auth("user@example.com", "");
 		$this->assertCount(sizeof($tests), $this->checkExceptions("user@example.org", $tests));
 	}
 
@@ -286,7 +291,7 @@ class TestAuthorization extends \PHPUnit\Framework\TestCase {
 			// list method does not take an affected user, so do not unshift for that one
 			if($func != "list") array_unshift($args, $user);
 			try {
-				call_user_func_array(array($this->data->user, $func), $args);
+				call_user_func_array(array(Data::$user, $func), $args);
 			} catch(User\ExceptionAuthz $e) {
 				$err[] = $func;
 			}
diff --git a/tests/User/TestUserInternalDriver.php b/tests/User/TestUserInternalDriver.php
index 6125abf..cd36c4a 100644
--- a/tests/User/TestUserInternalDriver.php
+++ b/tests/User/TestUserInternalDriver.php
@@ -9,18 +9,5 @@ class TestUserInternalDriver extends \PHPUnit\Framework\TestCase {
 	const USER1 = "john.doe@example.com";
 	const USER2 = "jane.doe@example.com";
 
-	protected $data;
-
-    function setUp() {
-		$drv = User\Internal\Driver::class;
-		$conf = new Conf();
-		$conf->userDriver = $drv;
-		$conf->userAuthPreferHTTP = true;
-		$this->data = new Test\RuntimeData($conf);
-		$this->data->db = new Test\User\Database($this->data);
-		$this->data->user = new User($this->data);
-		$this->data->user->authorizationEnabled(false);
-		$_SERVER['PHP_AUTH_USER'] = self::USER1;
-		$_SERVER['PHP_AUTH_PW'] = "secret";
-	}
+	public $drv = User\Internal\Driver::class;
 }
diff --git a/tests/User/TestUserMockExternal.php b/tests/User/TestUserMockExternal.php
index b24d607..98a3d4c 100644
--- a/tests/User/TestUserMockExternal.php
+++ b/tests/User/TestUserMockExternal.php
@@ -9,18 +9,5 @@ class TestUserMockExternal extends \PHPUnit\Framework\TestCase {
 	const USER1 = "john.doe@example.com";
 	const USER2 = "jane.doe@example.com";
 
-	protected $data;
-
-    function setUp() {
-		$drv = Test\User\DriverExternalMock::class;
-		$conf = new Conf();
-		$conf->userDriver = $drv;
-		$conf->userAuthPreferHTTP = true;
-		$this->data = new Test\RuntimeData($conf);
-		$this->data->db = new Test\User\Database($this->data);
-		$this->data->user = new User($this->data);
-		$this->data->user->authorizationEnabled(false);
-		$_SERVER['PHP_AUTH_USER'] = self::USER1;
-		$_SERVER['PHP_AUTH_PW'] = "secret";
-	}
+	public $drv = Test\User\DriverExternalMock::class;
 }
\ No newline at end of file
diff --git a/tests/User/TestUserMockInternal.php b/tests/User/TestUserMockInternal.php
index db3b703..3278d4d 100644
--- a/tests/User/TestUserMockInternal.php
+++ b/tests/User/TestUserMockInternal.php
@@ -9,17 +9,9 @@ class TestUserMockInternal extends \PHPUnit\Framework\TestCase {
 	const USER1 = "john.doe@example.com";
 	const USER2 = "jane.doe@example.com";
 
-	protected $data;
+	public $drv = Test\User\DriverInternalMock::class;
 
-    function setUp() {
-		$drv = Test\User\DriverInternalMock::class;
-		$conf = new Conf();
-		$conf->userDriver = $drv;
-		$conf->userAuthPreferHTTP = true;
-		$this->data = new Test\RuntimeData($conf);
-		$this->data->user = new User($this->data);
-		$this->data->user->authorizationEnabled(false);
-		$_SERVER['PHP_AUTH_USER'] = self::USER1;
-		$_SERVER['PHP_AUTH_PW'] = "secret";
+    function setUpSeries() {
+		Data::$db = null;
 	}
 }
diff --git a/tests/lib/Db/Tools.php b/tests/lib/Db/Tools.php
index 10d44ca..f18ae31 100644
--- a/tests/lib/Db/Tools.php
+++ b/tests/lib/Db/Tools.php
@@ -3,13 +3,16 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\Test\Db;
 
 trait Tools {
-	function prime(\JKingWeb\Arsse\Db\Driver $drv, array $data): bool {
+	protected $drv;
+	
+	
+	function prime(array $data): bool {
 		$drv->begin();
 		foreach($data as $table => $info) {
 			$cols = implode(",", array_keys($info['columns']));
 			$bindings = array_values($info['columns']);
 			$params = implode(",", array_fill(0, sizeof($info['columns']), "?"));
-			$s = $drv->prepareArray("INSERT INTO $table($cols) values($params)", $bindings);
+			$s = $this->drv->prepareArray("INSERT INTO $table($cols) values($params)", $bindings);
 			foreach($info['rows'] as $row) {
 				$this->assertEquals(1, $s->runArray($row)->changes());
 			}
@@ -18,13 +21,17 @@ trait Tools {
 		return true;
 	}
 
-	function compare(\JKingWeb\Arsse\Db\Driver $drv, array $expected): bool {
+	function compare(array $expected): bool {
 		foreach($expected as $table => $info) {
 			$cols = implode(",", array_keys($info['columns']));
-			foreach($drv->prepare("SELECT $cols from $table")->run() as $num => $row) {
+			foreach($this->drv->prepare("SELECT $cols from $table")->run() as $num => $row) {
 				$row = array_values($row);
 				$assertSame($expected[$table]['rows'][$num], $row, "Row $num of table $table does not match expectation.");
 			}
 		}
 	}
+
+	function setUp() {
+
+	}
 }
\ No newline at end of file
diff --git a/tests/lib/Lang/Setup.php b/tests/lib/Lang/Setup.php
index d1f9ec4..e5e67f3 100644
--- a/tests/lib/Lang/Setup.php
+++ b/tests/lib/Lang/Setup.php
@@ -1,16 +1,16 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Test\Lang;
-use \org\bovigo\vfs\vfsStream, \JKingWeb\Arsse\Lang;
+use org\bovigo\vfs\vfsStream;
+use JKingWeb\Arsse\Lang;
+use JKingWeb\Arsse\Data;
 
 
 
 trait Setup {
-    static function setUpBeforeClass() {
-        // this is required to keep from having exceptions in Lang::msg() in turn calling Lang::msg() and looping
-        \JKingWeb\Arsse\Lang\Exception::$test = true;
+    function setUp() {
         // test files
-        self::$files = [
+        $this->files = [
             'en.php'    => '<?php return ["Test.presentText" => "and the Philosopher\'s Stone"];',
             'en_ca.php' => '<?php return ["Test.presentText" => "{0} and {1}"];',
             'en_us.php' => '<?php return ["Test.presentText" => "and the Sorcerer\'s Stone"];',
@@ -28,22 +28,24 @@ trait Setup {
             // unreadable file
             'ru.php'    => '',
         ];
-        self::$vfs = vfsStream::setup("langtest", 0777, self::$files);
-        self::$path = self::$vfs->url()."/";
+        $vfs = vfsStream::setup("langtest", 0777, $this->files);
+        $this->path = $vfs->url()."/";
         // set up a file without read access
-        chmod(self::$path."ru.php", 0000);
-        // make the Lang class use the vfs files
-        self::$defaultPath = Lang::$path;
-        Lang::$path = self::$path;
+        chmod($this->path."ru.php", 0000);
+        // make the test Lang class use the vfs files
+        $this->l = new Lang($this->path);
+        // create a mock Lang object to keep exceptions from creating loops
+        $this->clearData(false);
+        $m = $this->getMockBuilder(Lang::class)->setMethods(['__invoke'])->getMock();
+        $m->expects($this->any())->method("__invoke")->with($this->anything(), $this->anything())->will($this->returnValue(""));
+        Data::$l = $m;
+        // call the additional setup method if it exists
+        if(method_exists($this, "setUpSeries")) $this->setUpSeries();
     }
 
-    static function tearDownAfterClass() {
-        \JKingWeb\Arsse\Lang\Exception::$test = false;
-        Lang::$path = self::$defaultPath;
-        self::$path = null;
-        self::$vfs = null;
-        self::$files = null;
-        Lang::set("", true);
-        Lang::set(Lang::DEFAULT);
+    function tearDown() {
+        $this->clearData(true);
+        // call the additional teardiwn method if it exists
+        if(method_exists($this, "tearDownSeries")) $this->tearDownSeries();
     }
 }
\ No newline at end of file
diff --git a/tests/lib/RuntimeData.php b/tests/lib/RuntimeData.php
deleted file mode 100644
index b3e1ce6..0000000
--- a/tests/lib/RuntimeData.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-declare(strict_types=1);
-namespace JKingWeb\Arsse\Test;
-
-class RuntimeData extends \JKingWeb\Arsse\RuntimeData {
-    public $conf;
-    public $db;
-    public $user;
-
-    public function __construct(\JKingWeb\Arsse\Conf $conf = null) {
-        $this->conf = $conf;
-    }
-}
\ No newline at end of file
diff --git a/tests/lib/Tools.php b/tests/lib/Tools.php
index ca3d734..a79d3fd 100644
--- a/tests/lib/Tools.php
+++ b/tests/lib/Tools.php
@@ -1,7 +1,8 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Test;
-use \JKingWeb\Arsse\Exception;
+use JKingWeb\Arsse\Exception;
+use JKingWeb\Arsse\Data;
 
 trait Tools {
     function assertException(string $msg, string $prefix = "", string $type = "Exception") {
@@ -15,4 +16,16 @@ trait Tools {
         $this->expectException($class);
         $this->expectExceptionCode($code);
     }
+
+    function clearData(bool $loadLang = true): bool {
+        $r = new \ReflectionClass(\JKingWeb\Arsse\Data::class);
+        $props = array_keys($r->getStaticProperties());
+        foreach($props as $prop) {
+            Data::$$prop = null;
+        }
+        if($loadLang) {
+            Data::$l = new \JKingWeb\Arsse\Lang();
+        }
+        return true;
+    }
 }
\ No newline at end of file
diff --git a/tests/lib/User/CommonTests.php b/tests/lib/User/CommonTests.php
index e80c762..146db9c 100644
--- a/tests/lib/User/CommonTests.php
+++ b/tests/lib/User/CommonTests.php
@@ -1,80 +1,105 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Test\User;
+use JKingWeb\Arsse\Data;
+use JKingWeb\Arsse\Conf;
+use JKingWeb\Arsse\User;
 use JKingWeb\Arsse\User\Driver;
 
 trait CommonTests {
+
+    function setUp() {
+		$this->clearData();
+		$conf = new Conf();
+		$conf->userDriver = $this->drv;
+		$conf->userAuthPreferHTTP = true;
+		Data::$conf = $conf;
+		Data::$db = new Database();
+		Data::$user = new User();
+		Data::$user->authorizationEnabled(false);
+		$_SERVER['PHP_AUTH_USER'] = self::USER1;
+		$_SERVER['PHP_AUTH_PW'] = "secret";
+        // call the additional setup method if it exists
+        if(method_exists($this, "setUpSeries")) $this->setUpSeries();
+	}
+
+	function tearDown() {
+		$this->clearData();
+        // call the additional teardiwn method if it exists
+        if(method_exists($this, "tearDownSeries")) $this->tearDownSeries();
+	}
+
 	function testListUsers() {
-		$this->assertCount(0,$this->data->user->list());
+		$this->assertCount(0,Data::$user->list());
 	}
 	
 	function testCheckIfAUserDoesNotExist() {
-		$this->assertFalse($this->data->user->exists(self::USER1));
+		$this->assertFalse(Data::$user->exists(self::USER1));
 	}
 
 	function testAddAUser() {
-		$this->data->user->add(self::USER1, "");
-		$this->assertCount(1,$this->data->user->list());
+		Data::$user->add(self::USER1, "");
+		$this->assertCount(1,Data::$user->list());
 	}
 
 	function testCheckIfAUserDoesExist() {
-		$this->data->user->add(self::USER1, "");
-		$this->assertTrue($this->data->user->exists(self::USER1));
+		Data::$user->add(self::USER1, "");
+		$this->assertTrue(Data::$user->exists(self::USER1));
 	}
 
 	function testAddADuplicateUser() {
-		$this->data->user->add(self::USER1, "");
+		Data::$user->add(self::USER1, "");
 		$this->assertException("alreadyExists", "User");
-		$this->data->user->add(self::USER1, "");
+		Data::$user->add(self::USER1, "");
 	}
 
 	function testAddMultipleUsers() {
-		$this->data->user->add(self::USER1, "");
-		$this->data->user->add(self::USER2, "");
-		$this->assertCount(2,$this->data->user->list());
+		Data::$user->add(self::USER1, "");
+		Data::$user->add(self::USER2, "");
+		$this->assertCount(2,Data::$user->list());
 	}
 	
 	function testRemoveAUser() {
-		$this->data->user->add(self::USER1, "");
-		$this->assertCount(1,$this->data->user->list());
-		$this->data->user->remove(self::USER1);
-		$this->assertCount(0,$this->data->user->list());
+		Data::$user->add(self::USER1, "");
+		$this->assertCount(1,Data::$user->list());
+		Data::$user->remove(self::USER1);
+		$this->assertCount(0,Data::$user->list());
 	}
 
 	function testRemoveAMissingUser() {
 		$this->assertException("doesNotExist", "User");
-		$this->data->user->remove(self::USER1);
+		Data::$user->remove(self::USER1);
 	}
 
 	function testAuthenticateAUser() {
 		$_SERVER['PHP_AUTH_USER'] = self::USER1;
 		$_SERVER['PHP_AUTH_PW'] = "secret";
-		$this->data->user->add(self::USER1, "secret");
-		$this->data->user->add(self::USER2, "");
-		$this->assertTrue($this->data->user->auth());
-		$this->assertTrue($this->data->user->auth(self::USER1, "secret"));
-		$this->assertFalse($this->data->user->auth(self::USER1, "superman"));
-		$this->assertTrue($this->data->user->auth(self::USER2, ""));
+		Data::$user->add(self::USER1, "secret");
+		Data::$user->add(self::USER2, "");
+		$this->assertTrue(Data::$user->auth());
+		$this->assertTrue(Data::$user->auth(self::USER1, "secret"));
+		$this->assertFalse(Data::$user->auth(self::USER1, "superman"));
+		$this->assertTrue(Data::$user->auth(self::USER2, ""));
 	}
 
 	function testChangeAPassword() {
-		$this->data->user->add(self::USER1, "secret");
-		$this->assertEquals("superman", $this->data->user->passwordSet(self::USER1, "superman"));
-		$this->assertTrue($this->data->user->auth(self::USER1, "superman"));
-		$this->assertFalse($this->data->user->auth(self::USER1, "secret"));
-		$this->assertEquals("", $this->data->user->passwordSet(self::USER1, ""));
-		$this->assertTrue($this->data->user->auth(self::USER1, ""));
-		$this->assertEquals($this->data->conf->userTempPasswordLength, strlen($this->data->user->passwordSet(self::USER1)));
+		Data::$user->add(self::USER1, "secret");
+		$this->assertEquals("superman", Data::$user->passwordSet(self::USER1, "superman"));
+		$this->assertTrue(Data::$user->auth(self::USER1, "superman"));
+		$this->assertFalse(Data::$user->auth(self::USER1, "secret"));
+		$this->assertEquals("", Data::$user->passwordSet(self::USER1, ""));
+		$this->assertTrue(Data::$user->auth(self::USER1, ""));
+		$this->assertEquals(Data::$conf->userTempPasswordLength, strlen(Data::$user->passwordSet(self::USER1)));
 	}
 
 	function testChangeAPasswordForAMissingUser() {
 		$this->assertException("doesNotExist", "User");
-		$this->data->user->passwordSet(self::USER1, "superman");
+		Data::$user->passwordSet(self::USER1, "superman");
 	}
 
 	function testGetThePropertiesOfAUser() {
-		$this->data->user->add(self::USER1, "secret");
-		$p = $this->data->user->propertiesGet(self::USER1);
+		Data::$user->add(self::USER1, "secret");
+		$p = Data::$user->propertiesGet(self::USER1);
 		$this->assertArrayHasKey('id', $p);
 		$this->assertArrayHasKey('name', $p);
 		$this->assertArrayHasKey('domain', $p);
@@ -97,22 +122,22 @@ trait CommonTests {
 			'domain' => 'example.com',
 			'rights' => Driver::RIGHTS_NONE,
 		];
-		$this->data->user->add(self::USER1, "secret");
-		$this->data->user->propertiesSet(self::USER1, $pSet);
-		$p = $this->data->user->propertiesGet(self::USER1);
+		Data::$user->add(self::USER1, "secret");
+		Data::$user->propertiesSet(self::USER1, $pSet);
+		$p = Data::$user->propertiesGet(self::USER1);
 		$this->assertArraySubset($pGet, $p);
 		$this->assertArrayNotHasKey('password', $p);
-		$this->assertFalse($this->data->user->auth(self::USER1, "superman"));
+		$this->assertFalse(Data::$user->auth(self::USER1, "superman"));
 	}
 
 	function testGetTheRightsOfAUser() {
-		$this->data->user->add(self::USER1, "");
-		$this->assertEquals(Driver::RIGHTS_NONE, $this->data->user->rightsGet(self::USER1));
+		Data::$user->add(self::USER1, "");
+		$this->assertEquals(Driver::RIGHTS_NONE, Data::$user->rightsGet(self::USER1));
 	}
 
 	function testSetTheRightsOfAUser() {
-		$this->data->user->add(self::USER1, "");
-		$this->data->user->rightsSet(self::USER1, Driver::RIGHTS_GLOBAL_ADMIN);
-		$this->assertEquals(Driver::RIGHTS_GLOBAL_ADMIN, $this->data->user->rightsGet(self::USER1));
+		Data::$user->add(self::USER1, "");
+		Data::$user->rightsSet(self::USER1, Driver::RIGHTS_GLOBAL_ADMIN);
+		$this->assertEquals(Driver::RIGHTS_GLOBAL_ADMIN, Data::$user->rightsGet(self::USER1));
 	}
 }
\ No newline at end of file
diff --git a/tests/lib/User/Database.php b/tests/lib/User/Database.php
index 458c136..0e3d761 100644
--- a/tests/lib/User/Database.php
+++ b/tests/lib/User/Database.php
@@ -1,6 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Test\User;
+use JKingWeb\Arsse\Data;
 use JKingWeb\Arsse\User\Driver;
 use JKingWeb\Arsse\User\Exception;
 use JKingWeb\Arsse\User\ExceptionAuthz;
@@ -10,48 +11,47 @@ class Database extends DriverSkeleton {
 
     public $db = [];
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-        $this->data = $data;
+    public function __construct() {
     }
 	
     function userExists(string $user): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         return parent::userExists($user);
     }
 
     function userAdd(string $user, string $password = null): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if($this->userExists($user)) throw new Exception("alreadyExists", ["action" => __FUNCTION__, "user" => $user]);
-        if($password===null) $password = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($password===null) $password = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         return parent::userAdd($user, $password);
     }
 
     function userRemove(string $user): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return parent::userRemove($user);
     }
 
     function userList(string $domain = null): array {
         if($domain===null) {
-            if(!$this->data->user->authorize("", __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => "global"]);
+            if(!Data::$user->authorize("", __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => "global"]);
             return parent::userList();
         } else {
             $suffix = '@'.$domain;
-            if(!$this->data->user->authorize($suffix, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $domain]);
+            if(!Data::$user->authorize($suffix, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $domain]);
             return parent::userList($domain);
         }
     }
     
     function userPasswordSet(string $user, string $newPassword = null, string $oldPassword = null): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
-        if($newPassword===null) $newPassword = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($newPassword===null) $newPassword = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         return parent::userPasswordSet($user, $newPassword);
     }
 
     function userPropertiesGet(string $user): array {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         $out = parent::userPropertiesGet($user);
         unset($out['password']);
@@ -59,20 +59,20 @@ class Database extends DriverSkeleton {
     }
 
     function userPropertiesSet(string $user, array $properties): array {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         parent::userPropertiesSet($user, $properties);
         return $this->userPropertiesGet($user);
     }
 
     function userRightsGet(string $user): int {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return parent::userRightsGet($user);
     }
     
     function userRightsSet(string $user, int $level): bool {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return parent::userRightsSet($user, $level);
     }
@@ -80,7 +80,7 @@ class Database extends DriverSkeleton {
     // specific to mock database
 
     function userPasswordGet(string $user): string {
-        if(!$this->data->user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
+        if(!Data::$user->authorize($user, __FUNCTION__)) throw new ExceptionAuthz("notAuthorized", ["action" => __FUNCTION__, "user" => $user]);
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
         return $this->db[$user]['password'];
     }
diff --git a/tests/lib/User/DriverExternalMock.php b/tests/lib/User/DriverExternalMock.php
index f6553b1..5de6eb2 100644
--- a/tests/lib/User/DriverExternalMock.php
+++ b/tests/lib/User/DriverExternalMock.php
@@ -1,6 +1,7 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\Arsse\Test\User;
+use JKingWeb\Arsse\Data;
 use JKingWeb\Arsse\User\Driver;
 use JKingWeb\Arsse\User\Exception;
 use PasswordGenerator\Generator as PassGen;
@@ -8,7 +9,6 @@ use PasswordGenerator\Generator as PassGen;
 class DriverExternalMock extends DriverSkeleton implements Driver {
 
     public $db = [];
-    protected $data;
     protected $functions = [
         "auth"                    => Driver::FUNC_EXTERNAL,
         "userList"                => Driver::FUNC_EXTERNAL,
@@ -22,10 +22,6 @@ class DriverExternalMock extends DriverSkeleton implements Driver {
         "userRightsSet"           => Driver::FUNC_EXTERNAL,
     ];
 
-    static public function create(\JKingWeb\Arsse\RuntimeData $data): Driver {
-        return new static($data);
-    }
-
     static public function driverName(): string {
         return "Mock External Driver";
     }
@@ -39,8 +35,7 @@ class DriverExternalMock extends DriverSkeleton implements Driver {
         }
     }
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-        $this->data = $data;
+    public function __construct() {
     }
 
     function auth(string $user, string $password): bool {
@@ -56,7 +51,7 @@ class DriverExternalMock extends DriverSkeleton implements Driver {
 
     function userAdd(string $user, string $password = null): string {
         if($this->userExists($user)) throw new Exception("alreadyExists", ["action" => __FUNCTION__, "user" => $user]);
-        if($password===null) $password = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($password===null) $password = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         return parent::userAdd($user, $password);
     }
 
@@ -75,7 +70,7 @@ class DriverExternalMock extends DriverSkeleton implements Driver {
     
     function userPasswordSet(string $user, string $newPassword = null, string $oldPassword = null): string {
         if(!$this->userExists($user)) throw new Exception("doesNotExist", ["action" => __FUNCTION__, "user" => $user]);
-        if($newPassword===null) $newPassword = (new PassGen)->length($this->data->conf->userTempPasswordLength)->get();
+        if($newPassword===null) $newPassword = (new PassGen)->length(Data::$conf->userTempPasswordLength)->get();
         return parent::userPasswordSet($user, $newPassword);
     }
 
diff --git a/tests/lib/User/DriverInternalMock.php b/tests/lib/User/DriverInternalMock.php
index b78c140..f9cec1c 100644
--- a/tests/lib/User/DriverInternalMock.php
+++ b/tests/lib/User/DriverInternalMock.php
@@ -6,7 +6,6 @@ use JKingWeb\Arsse\User\Driver;
 class DriverInternalMock extends Database implements Driver {
 
     public $db = [];
-    protected $data;
     protected $functions = [
         "auth"                    => Driver::FUNC_INTERNAL,
         "userList"                => Driver::FUNC_INTERNAL,
@@ -20,10 +19,6 @@ class DriverInternalMock extends Database implements Driver {
         "userRightsSet"           => Driver::FUNC_INTERNAL,
     ];
 
-    static public function create(\JKingWeb\Arsse\RuntimeData $data): Driver {
-        return new static($data);
-    }
-
     static public function driverName(): string {
         return "Mock Internal Driver";
     }
@@ -37,8 +32,7 @@ class DriverInternalMock extends Database implements Driver {
         }
     }
 
-    public function __construct(\JKingWeb\Arsse\RuntimeData $data) {
-        $this->data = $data;
+    public function __construct() {
     }
 
     function auth(string $user, string $password): bool {
diff --git a/tests/lib/User/DriverSkeleton.php b/tests/lib/User/DriverSkeleton.php
index d63680e..8d49a26 100644
--- a/tests/lib/User/DriverSkeleton.php
+++ b/tests/lib/User/DriverSkeleton.php
@@ -10,7 +10,6 @@ use PasswordGenerator\Generator as PassGen;
 abstract class DriverSkeleton {
 
 	protected $db = [];
-    protected $data;
 	
 	function userExists(string $user): bool {
         return array_key_exists($user, $this->db);
diff --git a/tests/phpunit.xml b/tests/phpunit.xml
index 6809e32..2331c18 100644
--- a/tests/phpunit.xml
+++ b/tests/phpunit.xml
@@ -10,10 +10,13 @@
     beStrictAboutTestSize="true"
     stopOnError="true">
 
-<testsuite name="Localization and exceptions">
+<testsuite name="Exceptions">
+    <file>Exception/TestException.php</file>
+</testsuite>
+
+<testsuite name="Localization">
     <file>Lang/TestLang.php</file>
     <file>Lang/TestLangComplex.php</file>
-    <file>Lang/TestException.php</file>
     <file>Lang/TestLangErrors.php</file>
 </testsuite>
 
diff --git a/tests/test.php b/tests/test.php
index 12eb764..449f729 100644
--- a/tests/test.php
+++ b/tests/test.php
@@ -3,6 +3,7 @@ namespace JKingWeb\Arsse;
 const INSTALL = true;
 require_once "../bootstrap.php";
 
+
 $user = "john.doe@example.com";
 $pass = "secret";
 $_SERVER['PHP_AUTH_USER'] = $user;
@@ -10,13 +11,13 @@ $_SERVER['PHP_AUTH_PW'] = $pass;
 $conf = new Conf();
 $conf->dbSQLite3File = ":memory:";
 $conf->userAuthPreferHTTP = true;
-$data = new RuntimeData($conf);
-$data->db->schemaUpdate();
+Data::load($conf);
+Data::$db->schemaUpdate();
 
-$data->user->add($user, $pass);
-$data->user->auth();
-$data->user->authorizationEnabled(false);
-$data->user->rightsSet($user, User\Driver::RIGHTS_GLOBAL_ADMIN);
-$data->user->authorizationEnabled(true);
-$data->db->folderAdd($user, ['name' => 'ook']);
-$data->db->subscriptionAdd($user, "http://www.tbray.org/ongoing/ongoing.atom");
\ No newline at end of file
+Data::$user->add($user, $pass);
+Data::$user->auth();
+Data::$user->authorizationEnabled(false);
+Data::$user->rightsSet($user, User\Driver::RIGHTS_GLOBAL_ADMIN);
+Data::$user->authorizationEnabled(true);
+Data::$db->folderAdd($user, ['name' => 'ook']);
+Data::$db->subscriptionAdd($user, "http://www.tbray.org/ongoing/ongoing.atom");
\ No newline at end of file