diff --git a/CHANGELOG.md b/CHANGELOG.md
index cddeac55..26e141e0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com), and this
 
   When trying to delete orphan visits the result will also be `0` and no visits will actually get deleted.
 
+* [#1879](https://github.com/shlinkio/shlink/issues/1879) Cache namespace can now be customized via config option or `CACHE_NAMESPACE` env var.
+
+  This is important if you are running multiple Shlink instance on the same server, or they share the same Redis instance (even more so if they are on different versions).
+
 ### Changed
 * [#1799](https://github.com/shlinkio/shlink/issues/1799) RoadRunner/openswoole jobs are not run anymore for tasks that are actually disabled.
 
diff --git a/composer.json b/composer.json
index 4b0bfc61..4f8ca4df 100644
--- a/composer.json
+++ b/composer.json
@@ -49,7 +49,7 @@
         "shlinkio/shlink-config": "dev-main#c0aa01f as 2.5",
         "shlinkio/shlink-event-dispatcher": "dev-main#bd3a62b as 3.1",
         "shlinkio/shlink-importer": "^5.1",
-        "shlinkio/shlink-installer": "^8.5",
+        "shlinkio/shlink-installer": "dev-develop#a665623 as 8.6",
         "shlinkio/shlink-ip-geolocation": "^3.2",
         "shlinkio/shlink-json": "^1.0",
         "spiral/roadrunner": "^2023.2",
@@ -72,7 +72,7 @@
         "phpstan/phpstan-phpunit": "^1.3",
         "phpstan/phpstan-symfony": "^1.3",
         "phpunit/php-code-coverage": "^10.1",
-        "phpunit/phpunit": "^10.3",
+        "phpunit/phpunit": "^10.4",
         "roave/security-advisories": "dev-master",
         "shlinkio/php-coding-standard": "~2.3.0",
         "shlinkio/shlink-test-utils": "^3.7.1",
diff --git a/config/autoload/cache.global.php b/config/autoload/cache.global.php
index 614b140f..94a9a183 100644
--- a/config/autoload/cache.global.php
+++ b/config/autoload/cache.global.php
@@ -16,7 +16,7 @@ return (static function (): array {
 
     return [
         'cache' => [
-            'namespace' => 'Shlink',
+            'namespace' => EnvVars::CACHE_NAMESPACE->loadFromEnv('Shlink'),
             ...$cacheRedisBlock,
         ],
         'redis' => $redis,
diff --git a/config/autoload/installer.global.php b/config/autoload/installer.global.php
index 966e36ee..0aa849e0 100644
--- a/config/autoload/installer.global.php
+++ b/config/autoload/installer.global.php
@@ -28,6 +28,7 @@ return [
             Option\Visit\VisitsThresholdConfigOption::class,
             Option\BasePathConfigOption::class,
             Option\TimezoneConfigOption::class,
+            Option\Cache\CacheNamespaceConfigOption::class,
             Option\Worker\TaskWorkerNumConfigOption::class,
             Option\Worker\WebWorkerNumConfigOption::class,
             Option\Redis\RedisServersConfigOption::class,
diff --git a/module/CLI/test/Util/CliTestUtils.php b/module/CLI/test/Util/CliTestUtils.php
index 62dd6e4f..9c92f882 100644
--- a/module/CLI/test/Util/CliTestUtils.php
+++ b/module/CLI/test/Util/CliTestUtils.php
@@ -22,8 +22,9 @@ class CliTestUtils
             $generator = new Generator();
         }
 
-        $command = $generator->getMock(
+        $command = $generator->testDouble(
             Command::class,
+            mockObject: true,
             callOriginalConstructor: false,
             callOriginalClone: false,
             cloneArguments: false,
diff --git a/module/Core/src/Config/EnvVars.php b/module/Core/src/Config/EnvVars.php
index ec7d384c..1a917928 100644
--- a/module/Core/src/Config/EnvVars.php
+++ b/module/Core/src/Config/EnvVars.php
@@ -17,6 +17,7 @@ enum EnvVars: string
     case DB_UNIX_SOCKET = 'DB_UNIX_SOCKET';
     case DB_PORT = 'DB_PORT';
     case GEOLITE_LICENSE_KEY = 'GEOLITE_LICENSE_KEY';
+    case CACHE_NAMESPACE = 'CACHE_NAMESPACE';
     case REDIS_SERVERS = 'REDIS_SERVERS';
     case REDIS_SENTINEL_SERVICE = 'REDIS_SENTINEL_SERVICE';
     case REDIS_PUB_SUB_ENABLED = 'REDIS_PUB_SUB_ENABLED';