diff --git a/app/decorators/helpers/avatar_helper.rb b/app/decorators/helpers/avatar_helper.rb
index 950c1d7..25cab44 100644
--- a/app/decorators/helpers/avatar_helper.rb
+++ b/app/decorators/helpers/avatar_helper.rb
@@ -1,16 +1,22 @@
 module AvatarHelper
 
   def avatar_image_tag
-    h.image_tag avatar_url, alt: (model.username || model.temporary_username), class: 'avatar'
+    h.image_tag avatar_url(model), alt: (model.username || model.temporary_username), class: 'avatar'
   end
 
-  private
+  module GravatarURL
+    def avatar_url(model)
+      username = model.username || model.temporary_username
+      email = model.email || "#{username}+#{model.id}@asciinema.org"
+      hash = Digest::MD5.hexdigest(email.downcase)
+      "//gravatar.com/avatar/#{hash}?s=128&d=retro"
+    end
+  end
 
-  def avatar_url
-    username = model.username || model.temporary_username
-    email = model.email || "#{username}+#{model.id}@asciinema.org"
-    hash = Digest::MD5.hexdigest(email.downcase)
-    "//gravatar.com/avatar/#{hash}?s=128&d=retro"
+  module TestAvatarURL
+    def avatar_url(model)
+      h.image_path 'favicon.png'
+    end
   end
 
 end
diff --git a/config/environments/development.rb b/config/environments/development.rb
index ddf0e90..21566e4 100644
--- a/config/environments/development.rb
+++ b/config/environments/development.rb
@@ -35,3 +35,5 @@ Rails.application.configure do
   # Raises error for missing translations
   # config.action_view.raise_on_missing_translations = true
 end
+
+AvatarHelper.include(AvatarHelper::GravatarURL)
diff --git a/config/environments/production.rb b/config/environments/production.rb
index 8d3f99a..beebb6b 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -76,3 +76,5 @@ Rails.application.configure do
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
 end
+
+AvatarHelper.include(AvatarHelper::GravatarURL)
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 6bbe9c4..2e2cc0e 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -37,3 +37,5 @@ Rails.application.configure do
   # Raises error for missing translations
   # config.action_view.raise_on_missing_translations = true
 end
+
+AvatarHelper.include(AvatarHelper::TestAvatarURL)
diff --git a/spec/decorators/helpers/avatar_helper_spec.rb b/spec/decorators/helpers/avatar_helper_spec.rb
index f4fab1a..1ee31a5 100644
--- a/spec/decorators/helpers/avatar_helper_spec.rb
+++ b/spec/decorators/helpers/avatar_helper_spec.rb
@@ -1,30 +1,23 @@
 require 'rails_helper'
 
-describe AvatarHelper do
+describe AvatarHelper::GravatarURL do
 
-  def expected_img(src)
-    %(<img alt="satyr" class="avatar" src="#{src.gsub('&', '&amp;')}" />)
-  end
-
-  let(:decorator) { double('decorator', h: h, model: model).
-                    extend(described_class) }
+  let(:decorator) { double('decorator').extend(described_class) }
   let(:model) { double('model', id: 1, username: 'satyr', email: email) }
 
-  describe '#avatar_image_tag' do
-    subject { decorator.avatar_image_tag }
+  describe '#avatar_url' do
+    subject { decorator.avatar_url(model) }
 
     context "when user has an email" do
       let(:email) { 'foo@email.com' }
 
-      it { should eq(expected_img(
-        '//gravatar.com/avatar/9dcfeb70fe212ea12562dddd22b0fc92?s=128&d=retro')) }
+      it { should eq('//gravatar.com/avatar/9dcfeb70fe212ea12562dddd22b0fc92?s=128&d=retro') }
     end
 
     context "when user has no email" do
       let(:email) { nil }
 
-      it { should eq(expected_img(
-        '//gravatar.com/avatar/40affe80f7becd02ac38d316f7fe7057?s=128&d=retro')) }
+      it { should eq('//gravatar.com/avatar/40affe80f7becd02ac38d316f7fe7057?s=128&d=retro') }
     end
   end