You can use Sidekiq with Upstash Redis. Sidekiq is a Ruby based queue library with a Redis-based queue storage so you can use with Upstash Redis.

Example Application

bundle init 
bundle add sidekiq
require "sidekiq"
require "sidekiq/api"
 
connection_url = ENV['UPSTASH_REDIS_LINK']
 
Sidekiq.configure_client do |config|
    config.redis = {url: connection_url}
end
 
Sidekiq.configure_server do |config|
    config.redis = {url: connection_url}
end
 
class EmailService
    include Sidekiq::Worker
    def perform(id, type)
        # Logic goes here. Let's assume sending email by printing to console.
        puts "Emailed to: " +  id + ": " + "'Congrats on " + type + " plan.'"
    end
end
 
def updateEmail(id, newType)
    jobFound = false
 
    a = Sidekiq::ScheduledSet.new
    a.each do |job|
        if job.args[0] == id
            job.delete
            jobFound = true
        end
    end
 
    if jobFound
        EmailService.perform_async(id, ("starting using our service and upgrading it to " + newType))
    else
        EmailService.perform_async(id, ("upgrading to " + newType))
    end
end
 
def sendEmail(id, type)
    case type
    when "free"
        # if free, delay for 10 seconds.
        EmailService.perform_in("10", id, "free")
    when "paid"
        # if paid, delay for 5 seconds.
        EmailService.perform_in("5", id, "paid")
    when "enterprise"
        # if enterprise, immediately queue.
        EmailService.perform_async(id, "enterprise")
    when "enterprise10k"
        EmailService.perform_async(id, "enterprise10k")
    else
        puts "Only plans are: `free`, `paid` and `enterprise`"
    end
end
 
def clearSchedules()
    Sidekiq::ScheduledSet.new.clear
    Sidekiq::Queue.new.clear
end

Billing Optimization

Sidekiq accesses Redis regularly, even when there is no queue activity. This can incur extra costs because Upstash charges per request on the Pay-As-You-Go plan. With the introduction of our Fixed plans, we recommend switching to a Fixed plan to avoid increased command count and high costs in Sidekiq use cases.