ruby 18 lines · 2 tabs

N+1 query detection with Bullet gem

Alex Kumar Jan 2026

2 tabs

Rails.application.configure do
  config.after_initialize do
    Bullet.enable = true
    Bullet.alert = false
    Bullet.bullet_logger = true
    Bullet.console = true
    Bullet.rails_logger = true
    Bullet.add_footer = true
    Bullet.skip_html_injection = false
  end
end

Rails.application.configure do
  config.after_initialize do
    Bullet.enable = true
    Bullet.raise = true
    Bullet.bullet_logger = true
  end
end

2 files · ruby Explain with highlit

N+1 queries are the silent performance killer in Rails apps—they're easy to introduce during rapid development and expensive to diagnose in production. The Bullet gem monitors queries during development and test runs, raising alerts when it detects missing eager_load, includes, or preload calls. I configure it to raise exceptions in test mode so the CI pipeline catches regressions before they reach production. The most valuable insight Bullet provides is distinguishing between true N+1 issues and acceptable single queries, which helps prioritize optimization efforts. Once Bullet is integrated, I can refactor with confidence knowing that I'm not accidentally removing necessary eager loading that prevents hundreds of roundtrips to the database.

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