ddev-dragonfly

A DDEV add-on that provides DragonflyDB as a Redis-compatible in-memory data store for local development.

DragonflyDB is a modern replacement for Redis that is fully compatible with the Redis API while offering better performance and lower memory usage for many workloads.

Installation

ddev add-on get ddev-dragonfly
ddev restart

After installation, the DragonflyDB service is available at dragonfly:6379 from within the DDEV network.

Commands

Examples

ddev redis-cli PING          # Returns PONG
ddev redis-cli SET foo bar   # Set a key
ddev redis-cli GET foo       # Get a key
ddev redis-cli INFO          # Server info
ddev redis-cli DBSIZE        # Number of keys
ddev dragonfly-flush          # Flush all keys

Configuration

Override defaults by setting environment variables in .ddev/config.yaml:

web_environment:
  - DRAGONFLY_DOCKER_IMAGE=docker.dragonflydb.io/dragonflydb/dragonfly:v1.25.5
  - DRAGONFLY_HOSTNAME=dragonfly

Default flags

The DragonflyDB container starts with these flags:

• --port=6379 — listen port
• --maxmemory=512mb — memory limit
• --cache_mode=true — automatic eviction of least-recently-used keys when memory limit is reached
• --proactor_threads=2 — number of I/O threads (suitable for local dev)

To customize flags, create a docker-compose.dragonfly_extra.yaml override:

services:
  dragonfly:
    command: dragonfly --port=6379 --maxmemory=1gb --cache_mode=true --proactor_threads=4

Drupal integration

For Drupal 9+ projects, the add-on automatically:

1. Copies settings.ddev.dragonfly.php to sites/default/
2. Appends an include line to settings.php

This configures Drupal’s Redis module to use DragonflyDB as the cache backend. You need the Redis module installed and the PhpRedis PHP extension enabled (included in DDEV by default).

Comparison with ddev-redis

Both add-ons use the same Drupal Redis module and PhpRedis extension. You can switch between them by removing one and installing the other.

Note: Do not run both ddev-redis and ddev-dragonfly simultaneously — they serve the same purpose and Drupal settings will conflict.

Removal

ddev add-on remove dragonfly
ddev restart

This removes the DragonflyDB container and cleans up settings.ddev.dragonfly.php from your Drupal site if it contains the #ddev-generated marker.