100rabhg/railswatch

Railswatch is a Ruby gem that adds a performance monitoring dashboard to a Ruby on Rails application. It is meant as a self-hosted and free alternative to commercial tools like New Relic APM or Datadog. The author says the gem is production-ready and is running it on two of their own applications, each with about a thousand daily unique users. Once installed, Railswatch tracks a wide range of metrics on your Rails app. It shows real-time recent requests, response time percentiles such as p50, p90, and p99, throughput in requests per minute, average response time, and the slowest controllers and actions. It also records the breakdown of time spent in views, the database, and SQL queries. Beyond raw web requests, it can monitor system resources like CPU, memory, and disk, simple crash reports for HTTP 500 errors, deployment or custom events, Sidekiq jobs, Delayed Job jobs, Grape API endpoints inside the Rails app, Rake tasks, and any custom block of code wrapped in Railswatch.measure. All of the captured data lives in your application's own database. Nothing is sent to a third party server. The README highlights that Railswatch does not need Redis for its own storage. If your application already uses Sidekiq then Sidekiq still uses Redis as usual, but Railswatch saves the job metrics into the database. Getting started is short. You add the gem to the Gemfile, run bundle install, run a Rails generator that creates an initializer and a migration, run db:migrate, then visit /railswatch in your app. You can store the monitoring data in your primary database or in a separate database defined in database.yml under a chosen connection name, which is useful for modern Rails multi-database setups. The README is firm about not leaving the dashboard open. In production you should protect it with HTTP Basic auth or with your own access check, for example by requiring current_user.admin?. The configuration file also lets you set retention windows, ignore specific endpoints or paths, attach custom request data, skip selected Rake tasks, and tune the recent and slow request tabs.