diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 847709634d..d97958714a 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -21,8 +21,8 @@
  * connect to a database, so anything reachable from here is reachable without a
  * running forum.
  *
- * Code that needs Config::$modSettings, User::$me or Db::$db is out of scope for
- * this suite and belongs in an integration suite running against a real install.
+ * Code that needs User::$me or Db::$db is out of scope for this suite and belongs
+ * in an integration suite running against a real install.
  */
 
 const TESTS_BOARDDIR = __DIR__ . '/..';
@@ -67,7 +67,7 @@
 /*
  * Paths and the default language, which the Unicode and entity helpers need in
  * order to locate their data files. These are the only pieces of Config the suite
- * sets: no modSettings, no database credentials, nothing read from Settings.php.
+ * sets: no database credentials and nothing read from Settings.php.
  * A test that needs more than this is an integration test.
  */
 SMF\Config::$boarddir = (string) realpath(TESTS_BOARDDIR);
@@ -78,3 +78,31 @@
 SMF\Config::$language = 'en_US';
 SMF\Config::$boardurl = 'test.local';
 SMF\Config::$scripturl = 'test.local/index.php';
+
+// Populate SMF\Config::$modSettings with default values.
+SMF\Lang::load('General+Maintenance', SMF\Config::$language);
+
+$replacements = [
+	'{$db_prefix}' => 'smf_',
+	'{$attachdir}' => json_encode([1 => addslashes(SMF\Config::$boarddir . '/attachments')]),
+	'{$boarddir}' => addslashes(SMF\Config::$boarddir),
+	'{$boardurl}' => SMF\Config::$boardurl,
+	'{$enableCompressedOutput}' => 0,
+	'{$databaseSession_enable}' => 0,
+	'{$smf_version}' => SMF_VERSION,
+	'{$current_time}' => time(),
+	'{$sched_task_offset}' => 82800 + mt_rand(0, 86399),
+	'{$registration_method}' => 0,
+];
+
+foreach (SMF\Lang::$txt as $key => $value) {
+	if (substr($key, 0, 8) == 'default_') {
+		$replacements['{$' . $key . '}'] = addslashes($value);
+	}
+}
+
+$replacements['{$default_reserved_names}'] = strtr($replacements['{$default_reserved_names}'], ['\\\\n' => "\n", '\\n' => "\n"]);
+
+foreach ((new \ReflectionClass(SMF\Db\Schema\v3_0\Settings::class))->getDefaultProperties()['initial_data'] as $setting) {
+	SMF\Config::$modSettings[$setting['variable']] = is_numeric($setting['value']) ? $setting['value'] + 0 : strtr($setting['value'], $replacements);
+}