presidentbeef/brakeman · error · NoBrakemanError

Cannot find lib/ directory.

Error message

Cannot find lib/ directory.

What it means

Early in `Brakeman.scan`, the library requires its own `brakeman/scanner` file; if that `require` raises `LoadError`, Brakeman reports `NoBrakemanError` with the misleading message 'Cannot find lib/ directory.' Despite the wording, this is about Brakeman's own library code not being loadable — a broken/partial gem installation or a corrupted Ruby load path — not about your application's `lib/` directory.

Source

Thrown at lib/brakeman.rb:450

        return "Brakeman #{current} is not the latest version #{latest_version}"
      else
        false
      end
    else
      false
    end
  end

  #Run a scan. Generally called from Brakeman.run instead of directly.
  def self.scan options
    #Load scanner
    scanner, tracker = nil

    process_step 'Loading scanner' do
      begin
        require 'brakeman/scanner'
      rescue LoadError
        raise NoBrakemanError, 'Cannot find lib/ directory.'
      end

      add_external_checks options

      #Start scanning
      scanner = Scanner.new options
      tracker = scanner.tracker

      check_for_missing_checks options[:run_checks], options[:skip_checks], options[:enable_checks]
    end

    logger.announce "Scanning #{tracker.app_path}"
    scanner.process

    tracker.run_checks

    self.filter_warnings tracker, options

View on GitHub (pinned to 649e678d0a)

Solutions

1. Run through bundler with brakeman in the Gemfile: add `gem 'brakeman', require: false` and invoke `bundle exec brakeman`.
2. Verify which Ruby and gem brakeman resolves to: `head -1 $(which brakeman)` and `gem which brakeman/scanner`; make sure both point at the same Ruby installation.
3. Reinstall the gem: `gem install brakeman` (and `rbenv rehash` / `rvm gems ... ` if applicable).
4. If running from a brakeman source checkout, launch it as `bundle exec bin/brakeman` from the checkout root so the local `lib/` is on the load path.

Example fix

# before (system brakeman shim, gem installed under a different Ruby)
brakeman .   # => Brakeman::NoBrakemanError: Cannot find lib/ directory.

# after (bundled, consistent Ruby)
bundle add brakeman --skip-install && bundle install && bundle exec brakeman .

# Ruby, smoke-test the install before invoking a scan
begin
  require 'brakeman/scanner'
rescue LoadError
  abort 'brakeman gem not loadable under this Ruby — run `bundle install` or `gem install brakeman`.'
end
Brakeman.run :app_path => app_path

begin
  Brakeman.run :app_path => app_path
rescue Brakeman::NoBrakemanError
  abort 'Brakeman library not loadable. Fix with `bundle exec brakeman` or reinstall the gem, then retry.'
end

When it happens

Trigger: `require 'brakeman/scanner'` failing: the brakeman gem is missing from the active Ruby's gem set (rbenv/rvm shim pointing at a different Ruby than the one with the gem installed), a corrupted partial gem install, running a checkout of brakeman's own source via `bin/brakeman` without the library on `$LOAD_PATH`, or a bundler context where brakeman is not in the Gemfile.

Common situations: Multiple Ruby installs (system Ruby vs rbenv/rvm) so `which brakeman` executes a shim whose Ruby lacks the gem; Docker images where `gem install brakeman` ran in a different layer/user than the runtime; running brakeman inside a fork/checkout of brakeman itself; `RUBYOPT`/`RUBYLIB` environment variables clobbering the load path; a Gemfile.lock resolution that dropped brakeman from the bundle.

Related errors

• Comparison file doesn't exist
• Parsing #{path} took too long (> #{@timeout} seconds). Try i
• Cannot specify output format if multiple output files specif
• Invalid GitHub repository format
• Could not find specified check#{missing.length > 1 ? 's' : '

AI-assisted analysis of presidentbeef/brakeman@649e678d0a (2026-08-21). Data as JSON: /api/errors/d3de9f176f58b2fc. Report an issue: GitHub.