diff --git a/.github/workflows/continuous-integration.yaml b/.github/workflows/continuous-integration.yaml
index 5746081c0..e3cc21b4c 100644
--- a/.github/workflows/continuous-integration.yaml
+++ b/.github/workflows/continuous-integration.yaml
@@ -113,6 +113,37 @@ jobs:
         run: |
           docker compose --file=docker/compose.proxy.yaml --file=docker/compose.es.yaml logs es01 es02
 
+  phpunit-lowest:
+    runs-on: 'ubuntu-24.04'
+    name: 'PHPUnit (lowest deps, PHP ${{ matrix.php }})'
+    timeout-minutes: 10
+    strategy:
+      matrix:
+        php:
+          - '8.1'
+      fail-fast: false
+    steps:
+      - name: 'Checkout'
+        uses: 'actions/checkout@v4'
+
+      - name: 'Setup PHP'
+        uses: 'shivammathur/setup-php@v2'
+        with:
+          php-version: '${{ matrix.php }}'
+          coverage: 'none'
+          tools: 'composer:v2'
+          extensions: 'curl, json, mbstring, openssl'
+
+      - name: 'Install dependencies with Composer (lowest)'
+        uses: 'ramsey/composer-install@v3'
+        with:
+          dependency-versions: 'lowest'
+          composer-options: '--prefer-dist --prefer-stable'
+
+      - name: 'Run unit tests'
+        run: |
+          vendor/bin/phpunit --group unit
+
   phpstan:
     runs-on: 'ubuntu-24.04'
     name: 'PHPStan'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b4e7e1579..6c7c7161a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Added support for "search after" based pagination [#1645](https://github.com/ruflin/Elastica/issues/1645)
 * Added support for the `seq_no_primary_term` search option and the `if_seq_no` / `if_primary_term` index options to enable optimistic concurrency control [#2284](https://github.com/ruflin/Elastica/pull/2284)
 ### Changed
+* Added a `phpunit-lowest` CI job that installs dependencies with `--prefer-lowest --prefer-stable` and runs the unit tests on PHP 8.1, ensuring that the minimum constraints declared in `composer.json` keep working.
 ### Deprecated
 ### Removed
 ### Fixed