diff --git a/src/AbstractDatabase.php b/src/AbstractDatabase.php
index 922bfeb4..db07c8dc 100644
--- a/src/AbstractDatabase.php
+++ b/src/AbstractDatabase.php
@@ -65,6 +65,8 @@ public function __construct(
 
     /**
      * ISO Standard Number
+     *
+     * @psalm-pure
      */
     abstract public static function getISONumber(): string;
 
diff --git a/src/Database/Countries.php b/src/Database/Countries.php
index 368aa17f..c306e81d 100644
--- a/src/Database/Countries.php
+++ b/src/Database/Countries.php
@@ -12,6 +12,11 @@
  */
 class Countries extends AbstractNotPartitionedDatabase
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '3166-1';
diff --git a/src/Database/Countries/Country.php b/src/Database/Countries/Country.php
index e6296477..90caab77 100644
--- a/src/Database/Countries/Country.php
+++ b/src/Database/Countries/Country.php
@@ -19,6 +19,8 @@ class Country
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/Currencies.php b/src/Database/Currencies.php
index e955ccdf..6932b6c2 100644
--- a/src/Database/Currencies.php
+++ b/src/Database/Currencies.php
@@ -12,6 +12,11 @@
  */
 class Currencies extends AbstractNotPartitionedDatabase
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '4217';
diff --git a/src/Database/Currencies/Currency.php b/src/Database/Currencies/Currency.php
index a1f2ff03..5495a4a8 100644
--- a/src/Database/Currencies/Currency.php
+++ b/src/Database/Currencies/Currency.php
@@ -31,6 +31,8 @@ class Currency
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/HistoricCountries.php b/src/Database/HistoricCountries.php
index 9b26e8b7..af2414b7 100644
--- a/src/Database/HistoricCountries.php
+++ b/src/Database/HistoricCountries.php
@@ -12,6 +12,11 @@
  */
 class HistoricCountries extends AbstractNotPartitionedDatabase
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '3166-3';
diff --git a/src/Database/HistoricCountries/Country.php b/src/Database/HistoricCountries/Country.php
index dd32a4c0..6b1201c1 100644
--- a/src/Database/HistoricCountries/Country.php
+++ b/src/Database/HistoricCountries/Country.php
@@ -19,6 +19,8 @@ class Country
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/Languages.php b/src/Database/Languages.php
index f6832807..12472c06 100644
--- a/src/Database/Languages.php
+++ b/src/Database/Languages.php
@@ -12,6 +12,11 @@
  */
 class Languages extends AbstractNotPartitionedDatabase implements LanguagesInterface
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '639-3';
diff --git a/src/Database/Languages/Language.php b/src/Database/Languages/Language.php
index 8a1ff129..53035d31 100644
--- a/src/Database/Languages/Language.php
+++ b/src/Database/Languages/Language.php
@@ -42,6 +42,8 @@ class Language
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/LanguagesPartitioned.php b/src/Database/LanguagesPartitioned.php
index 242b861e..ef23dd4b 100644
--- a/src/Database/LanguagesPartitioned.php
+++ b/src/Database/LanguagesPartitioned.php
@@ -9,6 +9,11 @@
 
 class LanguagesPartitioned extends AbstractPartitionedDatabase implements LanguagesInterface
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '639-3';
diff --git a/src/Database/Scripts.php b/src/Database/Scripts.php
index 70a9fd08..9c0f567a 100644
--- a/src/Database/Scripts.php
+++ b/src/Database/Scripts.php
@@ -12,6 +12,11 @@
  */
 class Scripts extends AbstractNotPartitionedDatabase
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '15924';
diff --git a/src/Database/Scripts/Script.php b/src/Database/Scripts/Script.php
index 944d595e..8151d4bc 100644
--- a/src/Database/Scripts/Script.php
+++ b/src/Database/Scripts/Script.php
@@ -19,6 +19,8 @@ class Script
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/Subdivisions.php b/src/Database/Subdivisions.php
index e08b5b3d..b15f44df 100644
--- a/src/Database/Subdivisions.php
+++ b/src/Database/Subdivisions.php
@@ -12,6 +12,11 @@
  */
 class Subdivisions extends AbstractNotPartitionedDatabase implements SubdivisionsInterface
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '3166-2';
diff --git a/src/Database/Subdivisions/Subdivision.php b/src/Database/Subdivisions/Subdivision.php
index 041b63e1..86987811 100644
--- a/src/Database/Subdivisions/Subdivision.php
+++ b/src/Database/Subdivisions/Subdivision.php
@@ -19,6 +19,8 @@ class Subdivision
 
     /**
      * @var string|null
+     *
+     * @psalm-allow-private-mutation
      */
     private $localName;
 
diff --git a/src/Database/SubdivisionsPartitioned.php b/src/Database/SubdivisionsPartitioned.php
index 27581c90..386c342d 100644
--- a/src/Database/SubdivisionsPartitioned.php
+++ b/src/Database/SubdivisionsPartitioned.php
@@ -9,6 +9,11 @@
 
 class SubdivisionsPartitioned extends AbstractPartitionedDatabase implements SubdivisionsInterface
 {
+    /**
+     * ISO Standard Number
+     *
+     * @psalm-pure
+     */
     public static function getISONumber(): string
     {
         return '3166-2';
diff --git a/src/TranslationDriver/DummyDriver.php b/src/TranslationDriver/DummyDriver.php
index 216a1ea3..e4a09f75 100644
--- a/src/TranslationDriver/DummyDriver.php
+++ b/src/TranslationDriver/DummyDriver.php
@@ -19,6 +19,12 @@ public function setLocale(string $locale): void
         // do nothing
     }
 
+    /**
+     * @param string $isoNumber
+     * @param string $message
+     *
+     * @return string
+     */
     public function translate(string $isoNumber, string $message): string
     {
         return $message;
diff --git a/src/TranslationDriver/GettextExtensionDriver.php b/src/TranslationDriver/GettextExtensionDriver.php
index 7deec449..797c7da4 100644
--- a/src/TranslationDriver/GettextExtensionDriver.php
+++ b/src/TranslationDriver/GettextExtensionDriver.php
@@ -39,6 +39,12 @@ public function setLocale(string $locale): void
         }
     }
 
+    /**
+     * @param string $isoNumber
+     * @param string $message
+     *
+     * @return string
+     */
     public function translate(string $isoNumber, string $message): string
     {
         return \dgettext($isoNumber, $message);
diff --git a/src/TranslationDriver/SymfonyTranslationDriver.php b/src/TranslationDriver/SymfonyTranslationDriver.php
index 917251bd..811d13a2 100644
--- a/src/TranslationDriver/SymfonyTranslationDriver.php
+++ b/src/TranslationDriver/SymfonyTranslationDriver.php
@@ -78,6 +78,12 @@ public function setLocale(string $locale): void
         $this->translator->setLocale($locale);
     }
 
+    /**
+     * @param string $isoNumber
+     * @param string $message
+     *
+     * @return string
+     */
     public function translate(string $isoNumber, string $message): string
     {
         return $this->translator->trans($message, [], $isoNumber);
diff --git a/src/TranslationDriver/TranslatorInterface.php b/src/TranslationDriver/TranslatorInterface.php
index 07457aae..c435d4af 100644
--- a/src/TranslationDriver/TranslatorInterface.php
+++ b/src/TranslationDriver/TranslatorInterface.php
@@ -6,5 +6,11 @@
 
 interface TranslatorInterface
 {
+    /**
+     * @param string $isoNumber
+     * @param string $message
+     *
+     * @return string
+     */
     public function translate(string $isoNumber, string $message): string;
 }
\ No newline at end of file