caution_tape 🚧

Visual environment indicators for Rack and Rails apps. Wraps non-production environments in unmistakable chrome — a striped construction frame and warning banner for staging/sandbox, a solid colored frame for development — so nobody ever mistakes a test environment for production (or puts production data in a sandbox).

  • Zero assets, zero JavaScript — a Rack middleware injects a small inline <style> + two <div>s before </body> on HTML responses.
  • Click-through (pointer-events: none) — never blocks the UI.
  • Off by default — production is safe unless you explicitly enable it.

Installation

bundle add caution_tape

Usage (Rails)

The Railtie installs the middleware automatically. Enable and style it per environment:

# config/environments/development.rb
CautionTape.configure do |c|
  c.enabled = true
  c.style   = :solid
  c.color   = "#dc2626"
  c.tag     = "Dev"
end

# config/environments/production.rb — same image serves prod and sandbox
CautionTape.configure do |c|
  c.enabled = ENV.fetch("BASE_URL", "").include?("sandbox")
  c.style   = :stripes
  c.banner  = "Sandbox — test environment. Do not enter real data."
end

Usage (plain Rack)

CautionTape.configure do |c|
  c.enabled = true
  c.banner  = "Staging"
end

use CautionTape::Middleware
run MyApp

Configuration

Option Default Notes
enabled false Nothing renders unless enabled
style :stripes :stripes (caution stripes) or :solid
color "#f5c518" Accent color; stripes pair it with near-black
banner nil Warning pill pinned top-center
tag nil Small label pill, shown when no banner is set
border_width 10 Frame thickness in px

Development

After checking out the repo, run bin/setup to install dependencies. Then run rake test to run the tests. You can also run bin/console for an interactive prompt.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/singlefeather/caution_tape. Contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.