diff --git a/.app_version b/.app_version
index 144996ed..88541566 100644
--- a/.app_version
+++ b/.app_version
@@ -1 +1 @@
-0.20.3
+0.21.0
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 32c90c57..f15d85e3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,13 +5,52 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-# 0.20.3 - 2024-12-20
+# 0.21.0 - 2024-12-20
+
+⚠️ This release introduces a breaking change. ⚠️
+
+The `dawarich_db` service now uses a custom `postgresql.conf` file.
+
+As @tabacha pointed out in #549, the default `shm_size` for the `dawarich_db` service is too small and it may lead to database performance issues. This release introduces a `shm_size` parameter to the `dawarich_db` service to increase the size of the shared memory for PostgreSQL. This should help database with peforming vacuum and other operations. Also, it introduces a custom `postgresql.conf` file to the `dawarich_db` service.
+
+To mount a custom `postgresql.conf` file, you need to create a `postgresql.conf` file in the `dawarich_db` service directory and add the following line to it:
+
+```diff
+  dawarich_db:
+    image: postgres:14.2-alpine
+    shm_size: 1G
+    container_name: dawarich_db
+    volumes:
+      - dawarich_db_data:/var/lib/postgresql/data
+      - dawarich_shared:/var/shared
++      - ./postgresql.conf:/etc/postgresql/postgresql.conf # Provide path to custom config
+  ...
+    healthcheck:
+      test: [ "CMD-SHELL", "pg_isready -U postgres -d dawarich_development" ]
+      interval: 10s
+      retries: 5
+      start_period: 30s
+      timeout: 10s
++    command: postgres -c config_file=/etc/postgresql/postgresql.conf # Use custom config
+```
+
+To ensure your database is using custom config, you can connect to the container (`docker exec -it dawarich_db psql -U postgres`) and run `SHOW config_file;` command. It should return the following path: `/etc/postgresql/postgresql.conf`.
 
 ### Added
 
-- A button on a year stats card to update stats for the whole year.
-- A button on a month stats card to update stats for a specific month.
+- A button on a year stats card to update stats for the whole year. #466
+- A button on a month stats card to update stats for a specific month. #466
 - A confirmation alert on the Notifications page before deleting all notifications.
+- A `shm_size` parameter to the `dawarich_db` service to increase the size of the shared memory for PostgreSQL. This should help database with peforming vacuum and other operations.
+
+```diff
+  ...
+  dawarich_db:
+    image: postgres:14.2-alpine
++    shm_size: 1G
+  ...
+```
+
 - In addition to `api_key` parameter, `Authorization` header is now being used to authenticate API requests. #543
 
 Example:
@@ -23,6 +62,7 @@ Authorization: Bearer YOUR_API_KEY
 ### Changed
 
 - The map borders were expanded to make it easier to scroll around the map for New Zealanders.
+- The `dawarich_db` service now uses a custom `postgresql.conf` file.
 
 # 0.20.2 - 2024-12-17
 
diff --git a/docker-compose.yml b/docker-compose.yml
index 4a41b272..68ad7846 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -18,10 +18,12 @@ services:
       timeout: 10s
   dawarich_db:
     image: postgres:14.2-alpine
+    shm_size: 1G
     container_name: dawarich_db
     volumes:
       - dawarich_db_data:/var/lib/postgresql/data
       - dawarich_shared:/var/shared
+      - ./postgresql.conf:/etc/postgresql/postgresql.conf # Provide path to your custom config
     networks:
       - dawarich
     environment:
@@ -34,6 +36,7 @@ services:
       retries: 5
       start_period: 30s
       timeout: 10s
+    command: postgres -c config_file=/etc/postgresql/postgresql.conf # Use custom config
   dawarich_app:
     image: freikin/dawarich:latest
     container_name: dawarich_app
diff --git a/postgres.conf.example b/postgres.conf.example
new file mode 100644
index 00000000..9e1687c3
--- /dev/null
+++ b/postgres.conf.example
@@ -0,0 +1,36 @@
+listen_addresses = '*'
+max_connections = 50
+
+shared_buffers = 512MB
+
+work_mem = 128MB
+maintenance_work_mem = 128MB
+
+
+dynamic_shared_memory_type = posix
+checkpoint_timeout = 10min              # range 30s-1d
+max_wal_size = 2GB
+min_wal_size = 80MB
+max_parallel_workers_per_gather = 4
+
+log_min_duration_statement = 500        # -1 is disabled, 0 logs all statements
+                                        # -1 disables, 0 logs all temp files
+log_timezone = 'UTC'
+
+
+autovacuum_vacuum_scale_factor = 0.05   # fraction of table size before vacuum
+autovacuum_analyze_scale_factor = 0.05  # fraction of table size before analyze
+
+
+datestyle = 'iso, dmy'
+
+timezone = 'UTC'
+
+lc_messages = 'en_US.utf8'                      # locale for system error message
+                                        # strings
+lc_monetary = 'en_US.utf8'                      # locale for monetary formatting
+lc_numeric = 'en_US.utf8'                       # locale for number formatting
+lc_time = 'en_US.utf8'                          # locale for time formatting
+
+
+default_text_search_config = 'pg_catalog.english'