diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cb79743..9e4a616 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macOS-latest]
-        php-version: ['8.1', '8.2']
+        php-version: ['8.2', '8.3']
         dependencies: ['lowest', 'highest']
     name: 'PHPUnit'
     steps:
@@ -33,7 +33,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-version: ['8.1', '8.2']
+        php-version: ['8.2', '8.3']
         dependencies: ['lowest', 'highest']
     name: 'Psalm'
     steps:
@@ -54,7 +54,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-version: ['8.1']
+        php-version: ['8.2']
     name: 'CS'
     steps:
       - name: Checkout
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7080341..a79119f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,15 @@
 # Changelog
 
+## 4.1.0 - 2023-09-23
+
+### Added
+
+- Support for `innmind/immutable:~5.0`
+
+### Removed
+
+- Support for PHP `8.1`
+
 ## 4.0.0 - 2023-01-29
 
 ### Changed
diff --git a/composer.json b/composer.json
index 984c282..fe75ca8 100644
--- a/composer.json
+++ b/composer.json
@@ -14,8 +14,8 @@
         "issues": "http://github.com/Innmind/ServerStatus/issues"
     },
     "require": {
-        "php": "~8.1",
-        "innmind/immutable": "~4.0",
+        "php": "~8.2",
+        "innmind/immutable": "~4.15|~5.0",
         "innmind/time-continuum": "~3.0",
         "innmind/url": "~4.0",
         "psr/log": "~3.0",
@@ -33,7 +33,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "~9.0",
-        "vimeo/psalm": "~4.30",
+        "vimeo/psalm": "~5.12",
         "innmind/coding-standard": "~2.0"
     }
 }
diff --git a/psalm.xml b/psalm.xml
index 3240886..510148d 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -2,6 +2,8 @@
 <psalm
     errorLevel="1"
     resolveFromConfigFile="true"
+    findUnusedCode="false"
+    findUnusedBaselineEntry="true"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns="https://getpsalm.org/schema/config"
     xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"