diff --git a/lib/deep_cover/cli/exec.rb b/lib/deep_cover/cli/exec.rb
index <HASH>..<HASH> 100755
--- a/lib/deep_cover/cli/exec.rb
+++ b/lib/deep_cover/cli/exec.rb
@@ -24,7 +24,7 @@ module DeepCover
 
       require 'yaml'
       env_var = {'DEEP_COVER' => 't',
-                 'DEEP_COVER_OPTIONS' => YAML.dump(processed_options.slice(*DEFAULTS.keys)),
+                 'DEEP_COVER_OPTIONS' => YAML.dump(processed_options.transform_keys(&:to_sym).slice(*DEFAULTS.keys)),
       }
 
       # Clear inspiration from Bundler's kernel_exec
Fix exec in <I>, looks like backport was helping us more than Ruby<I>