Installing Solid Queue

Introduction

Solid Queue is the default job backend in Rails 8, storing jobs in your database via Active Record. Setup takes a few commands with no external services required.

Key Concepts

• solid_queue:install: A Rails generator that sets up the schema, configuration, and Puma plugin.
• queue.yml: Configuration file defining dispatchers and workers.
• Database-backed: Jobs stored as rows, durable and queryable.

Real World Context

New Rails 8 apps have Solid Queue configured automatically. For existing apps upgrading, a single install command sets everything up.

Deep Dive

Installation

bash
bin/rails solid_queue:install

This creates:

• db/queue_schema.rb — database schema for job tables
• config/queue.yml — worker and dispatcher configuration
• Updates config/database.yml to add a queue database

Database Configuration

yaml
# config/database.yml
production:
  primary:
    <<: *default
    database: myapp_production
  queue:
    <<: *default
    database: myapp_production_queue
    migrations_paths: db/queue_migrate

ruby
# config/environments/production.rb
config.active_job.queue_adapter = :solid_queue
config.solid_queue.connects_to = { database: { writing: :queue } }

Running Solid Queue

bash
# Option 1: Puma plugin (automatic)
plugin :solid_queue  # in config/puma.rb

# Option 2: Standalone process
bin/jobs start

Common Pitfalls

1. Forgetting to create the queue database — Run bin/rails db:prepare after installation.
2. Using SQLite in production — Use PostgreSQL or MySQL for concurrent access.

Best Practices

1. Use a separate database for the queue — Prevents job locks from affecting application queries.
2. Run workers as separate processes in production — Scale independently of web servers.

Summary

• Install with bin/rails solid_queue:install.
• Jobs stored in a dedicated queue database.
• Puma plugin starts workers automatically, or run bin/jobs start.
• Always use PostgreSQL or MySQL in production.

# config/environments/production.rb
config.active_job.queue_adapter = :solid_queue
config.solid_queue.connects_to = { database: { writing: :queue } }