diff --git a/Guardfile b/Guardfile
index 8c6a19a..882a749 100644
--- a/Guardfile
+++ b/Guardfile
@@ -1,6 +1,6 @@
 # More info at https://github.com/guard/guard#readme
 
-guard 'rspec' do
+guard 'rspec', cli: '--tag ~speed:slow' do
   watch(%r{^spec/.+_spec\.rb$})
   watch(%r{^lib/(.+)\.rb$})        { |m| "spec/#{m[1]}_spec.rb" }
   watch(%r{^lib/(.+)/(.+)\.rb$})   { |m| "spec/#{m[1]}/#{m[2]}_spec.rb" }
diff --git a/spec/bashcov/runner_spec.rb b/spec/bashcov/runner_spec.rb
index ab34ca9..0ede7a4 100644
--- a/spec/bashcov/runner_spec.rb
+++ b/spec/bashcov/runner_spec.rb
@@ -9,7 +9,7 @@
       Bashcov::Runner.new('ls -l').run.should be_success
     end
 
-    it "is fast" do
+    it "is fast", speed: :slow do
       # XXX it's usually 2 to 3 times slower but can be up to 6 on Travis boxes
       # - not sure why :(
       ratio = 0