diff --git a/Gemfile b/Gemfile
index cf119cc1..45530c42 100644
--- a/Gemfile
+++ b/Gemfile
@@ -110,7 +110,7 @@ gem 'simple_enum'
 gem 'record_tag_helper'
 
 # Database
-gem 'mysql2'
+gem 'pg'
 
 group :development do
   gem 'rails-erd'
diff --git a/Gemfile.lock b/Gemfile.lock
index 6bf850ee..b61c515c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -197,7 +197,6 @@ GEM
     multi_xml (0.7.1)
       bigdecimal (~> 3.1)
     mutex_m (0.2.0)
-    mysql2 (0.5.6)
     net-http (0.4.1)
       uri
     net-imap (0.4.11)
@@ -251,6 +250,7 @@ GEM
     parser (3.3.1.0)
       ast (~> 2.4.1)
       racc
+    pg (1.5.6)
     poltergeist (1.18.1)
       capybara (>= 2.1, < 4)
       cliver (~> 0.3.1)
@@ -495,10 +495,10 @@ DEPENDENCIES
   letter_opener
   listen
   minitest (= 5.15.0)
-  mysql2
   omniauth-rails_csrf_protection
   omniauth-zeuswpi
   paper_trail
+  pg
   poltergeist
   puma
   rails (~> 6.1)
diff --git a/config/database.yml b/config/database.yml
index 48e222fd..697b91ed 100644
--- a/config/database.yml
+++ b/config/database.yml
@@ -1,21 +1,20 @@
 default: &default
-  adapter: mysql2
+  adapter: postgresql
   pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
   host: 127.0.0.1
-  port: 3306
-  database: gandalf
-  username: gandalf
+  username: postgres
   password: password
-  encoding: utf8mb4
-  collation: utf8mb4_unicode_ci
+  encoding: utf8
+  port: 5432
 
 development:
   <<: *default
+  database: gandalf
 
 test:
   <<: *default
   database: gandalf-test
-  port: 3307
+  port: 5433
 
 production:
   <<: *default
diff --git a/docker-compose.prod.yml b/docker-compose.prod.yml
index 5dd5b027..f3d533cc 100644
--- a/docker-compose.prod.yml
+++ b/docker-compose.prod.yml
@@ -2,17 +2,15 @@ version: '3.3'
 
 services:
   db:
-    image: mariadb:10.8
-    volumes:
-      - db_data:/var/lib/mysql
-    command: ['--character-set-server=utf8mb4', '--collation-server=utf8mb4_unicode_ci']
+    image: postgres:16
     environment:
-      MYSQL_ROOT_PASSWORD: strong-password
-      MYSQL_DATABASE: gandalf
-      MYSQL_USER: gandalf
-      MYSQL_PASSWORD: password
+      POSTGRES_DB: gandalf
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: password
+    volumes:
+      - gandalf_data:/var/lib/postgresql/data
     ports:
-      - "3306:3306"
+      - "5432:5432"
 
   web:
     build: .
@@ -23,7 +21,7 @@ services:
     volumes:
       - storage:/app/storage
     environment:
-      DATABASE_URL: mysql2://gandalf:password@db/gandalf
+      DATABASE_URL: postgresql://postgres:password@db/gandalf
       RAILS_LOG_TO_STDOUT: 1
       SECRET_AUTH_USERNAME: admin
       SECRET_AUTH_PASSWORD: admin-password
@@ -37,7 +35,7 @@ services:
     volumes:
       - storage:/app/storage
     environment:
-      DATABASE_URL: mysql2://gandalf:password@db/gandalf
+      DATABASE_URL: postgresql://postgres:password@db/gandalf
       REDIS_URL: redis://redis:6379
     entrypoint: bundle exec sidekiq
 
@@ -49,6 +47,6 @@ services:
       - "6379:6379"
 
 volumes:
-  db_data:
+  gandalf_data:
   redis_data:
   storage:
diff --git a/docker-compose.yml b/docker-compose.yml
index b1a6c3e0..0e82e694 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -2,30 +2,26 @@ version: '3.3'
 
 services:
   db:
-    image: mariadb:10.8
-    volumes:
-      - db_data:/var/lib/mysql
-    command: ['--character-set-server=utf8mb4', '--collation-server=utf8mb4_unicode_ci']
+    image: postgres:16
     environment:
-      MYSQL_ROOT_PASSWORD: strong-password
-      MYSQL_DATABASE: gandalf
-      MYSQL_USER: gandalf
-      MYSQL_PASSWORD: password
+      POSTGRES_DB: gandalf
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: password
+    volumes:
+      - gandalf_data:/var/lib/postgresql/data
     ports:
-      - "3306:3306"
+      - "5432:5432"
 
   db-test:
-    image: mariadb:10.8
-    volumes:
-      - db-test_data:/var/lib/mysql
-    command: ['--character-set-server=utf8mb4', '--collation-server=utf8mb4_unicode_ci']
+    image: postgres:16
     environment:
-      MYSQL_ROOT_PASSWORD: strong-password
-      MYSQL_DATABASE: gandalf-test
-      MYSQL_USER: gandalf
-      MYSQL_PASSWORD: password
+      POSTGRES_DB: gandalf-test
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: password
+    volumes:
+      - gandalf_test_data:/var/lib/postgresql/data
     ports:
-      - "3307:3306"
+      - "5433:5432"
 
   redis:
     image: redis:7-alpine
@@ -35,6 +31,6 @@ services:
       - "6379:6379"
 
 volumes:
-  db_data:
-  db-test_data:
+  gandalf_data:
+  gandalf_test_data:
   redis_data: