diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 290a5d0d19c7fdcc4381abcdd56be68ea17c4616..47534323faf0bcd8598e4c7c284e699aabf4a64d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -167,7 +167,7 @@ default:
       allow_failure: true
 
 # Default configuration.
-'DEFAULT: PHP 8.3 MySQL 8':
+'DEFAULT: PHP 8.3 MySQL 8.0':
   <<: *default-stage
   variables:
     _TARGET_PHP: "8.3-ubuntu"
@@ -185,7 +185,7 @@ default:
     - if: $PERFORMANCE_TEST == "1"
 
 # Re-run the pipeline, but with Composer updates.
-'DEFAULT: Updated dependencies (PHP 8.3 MySQL 8)':
+'DEFAULT: Updated dependencies (PHP 8.3 MySQL 8.0)':
   <<: *default-stage
   # Run daily and allow manual runs on MRs.
   rules:
@@ -200,7 +200,7 @@ default:
     include: .gitlab-ci.yml
 
 # Special job for MRs for test-only checks.
-'DEFAULT: Test-only (PHP 8.3 MySQL 8)':
+'DEFAULT: Test-only (PHP 8.3 MySQL 8.0)':
   <<: [ *default-stage, *with-composer ]
   when: manual
   allow_failure: true
@@ -224,6 +224,18 @@ default:
     _TARGET_PHP: "8.3-ubuntu"
     _TARGET_DB: "mariadb-10.6"
 
+'PHP 8.3 MySQL 8.4':
+  <<: [ *default-stage, *run-on-mr ]
+  variables:
+    _TARGET_PHP: "8.3-ubuntu"
+    _TARGET_DB: "mysql-8.4"
+
+'PHP 8.3 MySQL 9.0':
+  <<: [ *default-stage, *run-on-mr ]
+  variables:
+    _TARGET_PHP: "8.3-ubuntu"
+    _TARGET_DB: "mysql-9"
+
 'PHP 8.3 PostgreSQL 16':
   <<: [ *default-stage, *run-on-mr ]
   variables:
@@ -240,7 +252,7 @@ default:
 # The value set in the "needs" property will determine the order in the sequence.
 '[Commit] PHP 8.3 PostgreSQL 16':
   extends: 'PHP 8.3 PostgreSQL 16'
-  needs: [ 'DEFAULT: PHP 8.3 MySQL 8' ]
+  needs: [ 'DEFAULT: PHP 8.3 MySQL 8.0' ]
   <<: [ *run-on-commit ]
 
 '[Commit] PHP 8.3 SQLite 3.45':
@@ -252,7 +264,7 @@ default:
 # The value set in the "needs" property will determine the order in the sequence.
 '[Daily] PHP 8.3 PostgreSQL 16':
   extends: 'PHP 8.3 PostgreSQL 16'
-  needs: [ 'DEFAULT: PHP 8.3 MySQL 8' ]
+  needs: [ 'DEFAULT: PHP 8.3 MySQL 8.0' ]
   <<: [ *run-daily ]
 
 '[Daily] PHP 8.3 SQLite 3.45':
@@ -265,6 +277,11 @@ default:
   needs: [ '[Daily] PHP 8.3 SQLite 3.45' ]
   <<: [ *run-daily ]
 
+'[Daily] PHP 8.3 MySQL 8.4':
+  extends: 'PHP 8.3 MySQL 8.4'
+  needs: [ '[Daily] PHP 8.3 MariaDB 10.6' ]
+  <<: [ *run-daily ]
+
 ################
 # Lint Jobs
 ################