diff --git a/lib/common/browser.rb b/lib/common/browser.rb
index cb6d0ab2..033dd5ce 100644
--- a/lib/common/browser.rb
+++ b/lib/common/browser.rb
@@ -8,25 +8,36 @@ class Browser
   extend  Browser::Actions
   include Browser::Options
 
+  OPTIONS = [
+    :available_user_agents,
+    :basic_auth,
+    :cache_ttl,
+    :max_threads,
+    :user_agent,
+    :user_agent_mode,
+    :proxy,
+    :proxy_auth
+  ]
+
   @@instance = nil
 
-  attr_reader :hydra, :config_file
+  attr_reader :hydra, :config_file, :cache_dir
 
   # @param [ Hash ] options
+  # @options
   def initialize(options = {})
     @config_file = options[:config_file] || CONF_DIR + '/browser.conf.json'
-    @cache_dir   = CACHE_DIR + '/browser'
+    @cache_dir   = options[:cache_dir]   || CACHE_DIR + '/browser'
 
-    options.delete(:config_file)
+    #options.delete(:config_file)
 
     load_config()
 
-    if options.length > 0
-      override_config_with_options(options)
-    end
+    #if options.length > 0
+      override_config(options)
+    #end
 
     @hydra = Typhoeus::Hydra.new(max_concurrency: self.max_threads)
-    # TODO : add an argument for the cache dir instead of using a constant
     @cache = TyphoeusCache.new(@cache_dir)
     @cache.clean
 
@@ -47,7 +58,7 @@ class Browser
   end
 
   # TODO reload hydra (if the .load_config is called on a browser object,
-  # hydra will not have the new @max_threads and @request_timeout)
+  # hydra will not have the new @max_threads)
   def load_config(config_file = nil)
     @config_file = config_file || @config_file
 
@@ -57,20 +68,17 @@ class Browser
       data = JSON.parse(File.read(@config_file))
     end
 
-    Options::OPTIONS.each do |option|
+    OPTIONS.each do |option|
       option_name = option.to_s
 
-      if data[option_name]
+      unless data[option_name].nil?
         self.send(:"#{option_name}=", data[option_name])
       end
     end
   end
 
   def forge_request(url, params = {})
-    Typhoeus::Request.new(
-      url.to_s,
-      merge_request_params(params)
-    )
+    Typhoeus::Request.new(url, merge_request_params(params))
   end
 
   def merge_request_params(params = {})
diff --git a/lib/common/browser/options.rb b/lib/common/browser/options.rb
index 23ec2949..364ca346 100644
--- a/lib/common/browser/options.rb
+++ b/lib/common/browser/options.rb
@@ -3,18 +3,6 @@
 class Browser
   module Options
 
-    OPTIONS = [
-      :available_user_agents,
-      :basic_auth,
-      :cache_ttl,
-      :max_threads,
-      :user_agent,
-      :user_agent_mode,
-      :proxy,
-      :proxy_auth,
-      #:request_timeout,
-    ]
-
     USER_AGENT_MODES = %w{ static semi-static random }
 
     attr_reader   :basic_auth, :user_agent_mode, :proxy, :proxy_auth
@@ -31,9 +19,9 @@ class Browser
     # @return [ void ]
     def basic_auth=(auth)
       if auth.index(':')
-        @basic_auth = "Basic #{Base64.encode64(auth.chomp)}"
-      elsif auth =~ /\ABasic .*\z/
-        @basic_auth = auth.chomp
+        @basic_auth = "Basic #{Base64.encode64(auth).chomp}"
+      elsif auth =~ /\ABasic [a-zA-Z0-9=]+\z/
+        @basic_auth = auth
       else
        raise 'Invalid basic authentication format, "login:password" or "Basic base_64_encoded" expected'
      end
@@ -80,7 +68,10 @@ class Browser
 
     # Sets the proxy
     # Accepted format:
-    #   host:post
+    #   [protocol://]host:post
+    #
+    #  Supported protocols:
+    #    Depends on the curl protocols, See curl --version
     #
     # @param [ String ] proxy
     #
@@ -89,7 +80,7 @@ class Browser
       if proxy.index(':')
         @proxy = proxy
       else
-        raise 'Invalid proxy format. Should be host:port.'
+        raise 'Invalid proxy format. Should be [protocol://]host:port.'
       end
     end
 
@@ -123,7 +114,7 @@ class Browser
     # @param [ Hash ] options
     #
     # @return [ void ]
-    def override_config_with_options(options = {})
+    def override_config(options = {})
       options.each do |option, value|
         if value != nil and OPTIONS.include?(option)
           self.send(:"#{option}=", value)
diff --git a/spec/lib/common/browser_spec.rb b/spec/lib/common/browser_spec.rb
index e3c4b0b2..7fe078b5 100644
--- a/spec/lib/common/browser_spec.rb
+++ b/spec/lib/common/browser_spec.rb
@@ -8,12 +8,16 @@ describe Browser do
 
   CONFIG_FILE_WITHOUT_PROXY       = SPEC_FIXTURES_CONF_DIR + '/browser/browser.conf.json'
   CONFIG_FILE_WITH_PROXY          = SPEC_FIXTURES_CONF_DIR + '/browser/browser.conf_proxy.json'
-  CONFIG_FILE_WITH_PROXY_AND_AUTH = SPEC_FIXTURES_CONF_DIR + '/browser/browser.conf_proxy_auth.json'
-  INSTANCE_VARS_TO_CHECK          = ['user_agent', 'user_agent_mode', 'available_user_agents', 'proxy', 'max_threads', 'cache_ttl']
+  #CONFIG_FILE_WITH_PROXY_AND_AUTH = SPEC_FIXTURES_CONF_DIR + '/browser/browser.conf_proxy_auth.json'
 
   subject(:browser) {
-    Browser::reset
-    Browser.instance
+    Browser.reset
+    Browser.instance(options)
+  }
+  let(:options) { {} }
+  let(:instance_vars_to_check) {
+    ['user_agent', 'user_agent_mode', 'available_user_agents', 'proxy',
+     'max_threads', 'cache_ttl']
   }
 
   before :all do
@@ -21,146 +25,11 @@ describe Browser do
     @json_config_with_proxy    = JSON.parse(File.read(CONFIG_FILE_WITH_PROXY))
   end
 
-  before :each do
-    Browser::reset
-    @browser = Browser.instance(config_file: CONFIG_FILE_WITHOUT_PROXY)
-  end
-
   def check_instance_variables(browser, json_expected_vars)
     json_expected_vars['max_threads'] ||= 1 # max_thread can not be nil
 
-    INSTANCE_VARS_TO_CHECK.each do |instance_variable_name|
-      browser.send(:"#{instance_variable_name}").should === json_expected_vars[instance_variable_name]
-    end
-  end
-
-  describe '#user_agent_mode setter / getter' do
-    # Testing all valid modes
-    Browser::USER_AGENT_MODES.each do |user_agent_mode|
-      it "should set / return #{user_agent_mode}" do
-        @browser.user_agent_mode = user_agent_mode
-        @browser.user_agent_mode.should === user_agent_mode
-      end
-    end
-
-    it "shoud set the mode to 'static' if nil is given" do
-      @browser.user_agent_mode = nil
-      @browser.user_agent_mode.should === 'static'
-    end
-
-    it 'should raise an error if the mode in not valid' do
-      expect { @browser.user_agent_mode = 'invalid-mode' }.to raise_error
-    end
-  end
-
-  #describe '#max_threads=' do
-  #  it 'should set max_threads to 1 if nil is given' do
-  #    @browser.max_threads = nil
-  #    @browser.max_threads.should === 1
-  #  end
-#
-  #  it 'should set max_threads to 1 if 0 is given' do
-  #    @browser.max_threads = 0
-  #    @browser.max_threads.should === 1
-  #  end
-  #end
-
-  describe '#proxy_auth=' do
-    after :each do
-      if @raise_error
-        expect { @browser.proxy_auth = @proxy_auth }.to raise_error
-      else
-        @browser.proxy_auth = @proxy_auth
-        @browser.proxy_auth.should === @expected
-      end
-    end
-
-    context 'when the auth supplied is' do
-
-      context 'not a String or a Hash' do
-        it 'raises an error' do
-          @proxy_auth  = 10
-          @raise_error = true
-        end
-      end
-
-      context 'a String with' do
-        context 'invalid format' do
-          it 'raises an error' do
-            @proxy_auth  = 'invaludauthformat'
-            @raise_error = true
-          end
-        end
-
-        context 'valid format' do
-           it 'sets the auth' do
-            @proxy_auth = 'username:passwd'
-            @expected   = @proxy_auth
-          end
-        end
-      end
-
-      context 'a Hash with' do
-        context 'only :proxy_username' do
-          it 'raises an error' do
-            @proxy_auth  = { proxy_username: 'username' }
-            @raise_error = true
-          end
-        end
-
-        context 'only :proxy_password' do
-          it 'raises an error' do
-            @proxy_auth  = { proxy_password: 'hello' }
-            @raise_error = true
-          end
-        end
-
-        context ':proxy_username and :proxy_password' do
-          it 'sets the auth' do
-            @proxy_auth = { proxy_username: 'user', proxy_password: 'pass' }
-            @expected   = 'user:pass'
-          end
-        end
-      end
-
-    end
-  end
-
-  describe '#user_agent' do
-    available_user_agents = %w{ ua-1 ua-2 ua-3 ua-4 ua-6 ua-7 ua-8 ua-9 ua-10 ua-11 ua-12 ua-13 ua-14 ua-15 ua-16 ua-17 }
-
-    it 'should always return the same user agent in static mode' do
-      @browser.user_agent = 'fake UA'
-      @browser.user_agent_mode = 'static'
-
-      (1..3).each do
-        @browser.user_agent.should === 'fake UA'
-      end
-    end
-
-    it 'should choose a random user_agent in the available_user_agents array an always return it' do
-      @browser.available_user_agents = available_user_agents
-      @browser.user_agent = 'Firefox 11.0'
-      @browser.user_agent_mode = 'semi-static'
-
-      user_agent = @browser.user_agent
-      user_agent.should_not === 'Firefox 11.0'
-      available_user_agents.include?(user_agent).should be_true
-
-      (1..3).each do
-        @browser.user_agent.should === user_agent
-      end
-    end
-
-    it 'should return a random user agent each time' do
-      @browser.available_user_agents = available_user_agents
-      @browser.user_agent_mode = 'random'
-
-      ua_1 = @browser.user_agent
-      ua_2 = @browser.user_agent
-      ua_3 = @browser.user_agent
-
-      fail if ua_1 === ua_2 and ua_2 === ua_3
+    instance_vars_to_check.each do |variable_name|
+      browser.send(:"#{variable_name}").should === json_expected_vars[variable_name]
     end
   end
 
@@ -170,48 +39,32 @@ describe Browser do
     end
   end
 
-  describe "#instance with :config_file = #{CONFIG_FILE_WITHOUT_PROXY}" do
-    it 'will check the instance vars' do
-      Browser.reset
-      check_instance_variables(
-        Browser.instance(config_file: CONFIG_FILE_WITHOUT_PROXY),
-        @json_config_without_proxy
-      )
-    end
-  end
+  describe '::instance' do
+    after { check_instance_variables(browser, @json_expected_vars) }
 
-  describe "#instance with :config_file = #{CONFIG_FILE_WITH_PROXY}" do
-    it 'will check the instance vars' do
-      Browser.reset
-      check_instance_variables(
-        Browser.instance(config_file: CONFIG_FILE_WITH_PROXY),
-        @json_config_with_proxy
-      )
-    end
-  end
-
-  # TODO Write something to test all possible overriding
-  describe 'override option : user_agent & threads' do
-    it 'will check the instance vars, with an overriden one' do
-      Browser.reset
-      check_instance_variables(
-        Browser.instance(
-          config_file: CONFIG_FILE_WITHOUT_PROXY,
-          user_agent: 'fake IE'
-        ),
-        @json_config_without_proxy.merge('user_agent' => 'fake IE')
-      )
+    context "when default config_file = #{CONFIG_FILE_WITHOUT_PROXY}" do
+      it 'will check the instance vars' do
+        @json_expected_vars = @json_config_without_proxy
+      end
     end
 
-    it 'should not override the max_threads if max_threads = nil' do
-      Browser.reset
-      check_instance_variables(
-        Browser.instance(
-          config_file: CONFIG_FILE_WITHOUT_PROXY,
-          max_threads: nil
-        ),
-        @json_config_without_proxy
-      )
+    context "when :config_file = #{CONFIG_FILE_WITH_PROXY}" do
+      let(:options) { { config_file: CONFIG_FILE_WITH_PROXY } }
+
+      it 'will check the instance vars' do
+        @json_expected_vars = @json_config_with_proxy
+      end
+    end
+
+    context 'when options[:cache_dir]' do
+      let(:cache_dir) { CACHE_DIR + '/somewhere' }
+      let(:options) { { cache_dir: cache_dir } }
+
+      after { subject.cache_dir.should == cache_dir }
+
+      it 'sets @cache_dir' do
+        @json_expected_vars = @json_config_without_proxy
+      end
     end
   end
 
@@ -219,7 +72,6 @@ describe Browser do
   describe '#load_config' do
     it 'should raise an error if file is a symlink' do
       symlink = './rspec_symlink'
-      browser = Browser.instance
 
       File.symlink('./testfile', symlink)
       expect { browser.load_config(symlink) }.to raise_error("[ERROR] Config file is a symlink.")
@@ -227,7 +79,7 @@ describe Browser do
     end
   end
 
-  describe '#append_params_header_field' do
+  describe '::append_params_header_field' do
     after :each do
       Browser.append_params_header_field(
         @params,
@@ -264,7 +116,6 @@ describe Browser do
         end
       end
     end
-
   end
 
   describe '#merge_request_params' do
@@ -280,10 +131,10 @@ describe Browser do
     }
 
     after :each do
-      @browser.stub(user_agent: 'SomeUA')
-      @browser.cache_ttl = 250
+      browser.stub(user_agent: 'SomeUA')
+      browser.cache_ttl = 250
 
-      @browser.merge_request_params(params).should == @expected
+      browser.merge_request_params(params).should == @expected
     end
 
     it 'sets the User-Agent header field and cache_ttl' do
@@ -296,27 +147,26 @@ describe Browser do
       let(:proxy_expectation) { default_expectation.merge(proxy: proxy) }
 
       it 'merges the proxy' do
-        @browser.proxy = proxy
-        @expected      = proxy_expectation
+        browser.proxy = proxy
+        @expected     = proxy_expectation
       end
 
       context 'when @proxy_auth' do
         it 'sets the proxy_auth' do
-          @browser.proxy      = proxy
-          @browser.proxy_auth = 'user:pass'
-          @expected           = proxy_expectation.merge(proxyauth: 'user:pass')
+          browser.proxy      = proxy
+          browser.proxy_auth = 'user:pass'
+          @expected          = proxy_expectation.merge(proxyauth: 'user:pass')
         end
       end
     end
 
     context 'when @basic_auth' do
       it 'appends the basic_auth' do
-        @browser.basic_auth = 'user:pass'
+        browser.basic_auth  = 'user:pass'
         @expected           = default_expectation.merge(
-          headers: default_expectation[:headers].merge('Authorization' => 'Basic '+Base64.encode64('user:pass'))
+          headers: default_expectation[:headers].merge('Authorization' => 'Basic '+Base64.encode64('user:pass').chomp)
         )
       end
-
     end
 
     context 'when the cache_ttl is alreday set' do
@@ -326,11 +176,19 @@ describe Browser do
         @expected = default_expectation.merge(params)
       end
     end
-
   end
 
-  # TODO
   describe '#forge_request' do
+    let(:url) { 'http://example.localhost' }
+
+    it 'returns the correct Typhoeus::Request' do
+      subject.stub(merge_request_params: { cache_ttl: 10 })
+
+      request = subject.forge_request(url)
+      request.should be_a Typhoeus::Request
+      request.url.should == url
+      request.cache_ttl.should == 10
+    end
 
   end
 
@@ -359,4 +217,3 @@ describe Browser do
     end
   end
 end
-
diff --git a/spec/shared_examples/browser/options.rb b/spec/shared_examples/browser/options.rb
index a6a6378b..01011c35 100644
--- a/spec/shared_examples/browser/options.rb
+++ b/spec/shared_examples/browser/options.rb
@@ -2,32 +2,250 @@
 
 shared_examples 'Browser::Options' do
 
-  describe 'basic_auth=' do
+  describe '#basic_auth=' do
+    let(:exception) { 'Invalid basic authentication format, "login:password" or "Basic base_64_encoded" expected' }
 
+    after do
+      if @expected
+        subject.basic_auth = @auth
+        subject.basic_auth.should == @expected
+      else
+        expect { subject.basic_auth = @auth }.to raise_error(exception)
+      end
+    end
+
+    context 'when invalid format' do
+      it 'raises an error' do
+        @auth = 'invalid'
+      end
+    end
+
+    context 'when login:password' do
+      it 'sets the basic auth' do
+        @auth     = 'admin:weakpass'
+        @expected = 'Basic YWRtaW46d2Vha3Bhc3M='
+      end
+    end
+
+    context 'when Basic base_64_encoded' do
+      context 'when invalid base_64_encoded' do
+        it 'raises an error' do
+          @auth = 'Basic <script>alert(1)</script>'
+        end
+      end
+
+      it 'sets the basic auth' do
+        @auth     = 'Basic dXNlcm5hbWU6dGhlYmlncGFzc3dvcmRzb3dlYWs='
+        @expected = @auth
+      end
+    end
   end
 
-  describe 'max_threads' do
+  describe '#max_threads' do
+    after do
+      subject.max_threads = @max_threads
+      subject.max_threads.should == @expected
+    end
 
+    context 'when no @max_threads' do
+      @max_threads = nil
+      @expected    = 1
+    end
+
+    context 'when @max_threads' do
+      it 'returns the @max_threads' do
+        @max_threads = 10
+        @expected    = 10
+      end
+    end
   end
 
-  describe 'user_agent=' do
+  describe '#user_agent_mode= & #user_agent_mode' do
+    # Testing all valid modes
+    Browser::USER_AGENT_MODES.each do |user_agent_mode|
+      it "sets & returns #{user_agent_mode}" do
+        subject.user_agent_mode = user_agent_mode
+        subject.user_agent_mode.should === user_agent_mode
+      end
+    end
 
+    it 'sets the mode to "static" if nil is given' do
+      subject.user_agent_mode = nil
+      subject.user_agent_mode.should === 'static'
+    end
+
+    it 'raises an error if the mode is not valid' do
+      expect { subject.user_agent_mode = 'invalid-mode' }.to raise_error
+    end
   end
 
-  describe 'user_agent' do
+  describe '#user_agent= & #user_agent' do
+    let(:available_user_agents) { %w{ ua-1 ua-2 ua-3 ua-4 ua-6 ua-7 ua-8 ua-9 ua-10 ua-11 ua-12 ua-13 ua-14 ua-15 ua-16 ua-17 } }
 
+    context 'when static mode' do
+      it 'returns the same user agent' do
+        subject.user_agent = 'fake UA'
+        subject.user_agent_mode = 'static'
+
+        (1..3).each do
+          subject.user_agent.should === 'fake UA'
+        end
+      end
+    end
+
+    context 'when semi-static mode' do
+      it 'chooses a random user_agent in the available_user_agents array and always return it' do
+        subject.available_user_agents = available_user_agents
+        subject.user_agent            = 'Firefox 11.0'
+        subject.user_agent_mode       = 'semi-static'
+
+        user_agent = subject.user_agent
+        user_agent.should_not === 'Firefox 11.0'
+        available_user_agents.include?(user_agent).should be_true
+
+        (1..3).each do
+          subject.user_agent.should === user_agent
+        end
+      end
+    end
+
+    context 'when random' do
+      it 'returns a random user agent each time' do
+        subject.available_user_agents = available_user_agents
+        subject.user_agent_mode       = 'random'
+
+        ua_1 = subject.user_agent
+        ua_2 = subject.user_agent
+        ua_3 = subject.user_agent
+
+        fail if ua_1 === ua_2 and ua_2 === ua_3
+      end
+    end
   end
 
   describe 'proxy=' do
+    let(:exception) { 'Invalid proxy format. Should be [protocol://]host:port.' }
 
+    after do
+      if @expected
+        subject.proxy = @proxy
+        subject.proxy.should == @expected
+      else
+        expect { subject.proxy = @proxy }.to raise_error(exception)
+      end
+    end
+
+    context 'when invalid format' do
+      it 'raises an error' do
+        @proxy = 'yolo'
+      end
+    end
+
+    context 'when valid format' do
+      @proxy    = '127.0.0.1:9050'
+      @expected = @proxy
+    end
   end
 
   describe 'proxy_auth=' do
+    let(:exception) { 'Invalid proxy auth format, expected username:password or {proxy_username: username, proxy_password: password}' }
 
+    after :each do
+      if @expected
+        subject.proxy_auth = @proxy_auth
+        subject.proxy_auth.should === @expected
+      else
+        expect { subject.proxy_auth = @proxy_auth }.to raise_error
+      end
+    end
+
+    context 'when the auth supplied is' do
+      context 'not a String or a Hash' do
+        it 'raises an error' do
+          @proxy_auth = 10
+        end
+      end
+
+      context 'a String with' do
+        context 'invalid format' do
+          it 'raises an error' do
+            @proxy_auth = 'invaludauthformat'
+          end
+        end
+
+        context 'valid format' do
+           it 'sets the auth' do
+            @proxy_auth = 'username:passwd'
+            @expected   = @proxy_auth
+          end
+        end
+      end
+
+      context 'a Hash with' do
+        context 'only :proxy_username' do
+          it 'raises an error' do
+            @proxy_auth = { proxy_username: 'username' }
+          end
+        end
+
+        context 'only :proxy_password' do
+          it 'raises an error' do
+            @proxy_auth = { proxy_password: 'hello' }
+          end
+        end
+
+        context ':proxy_username and :proxy_password' do
+          it 'sets the auth' do
+            @proxy_auth = { proxy_username: 'user', proxy_password: 'pass' }
+            @expected   = 'user:pass'
+          end
+        end
+      end
+    end
   end
 
-  describe 'override_config_with_options' do
+  describe '#override_config' do
+    after do
+      subject.send(:override_config, override_options)
+    end
 
+    let(:config) { JSON.parse(File.read(subject.config_file)) }
+
+    context 'when an option value is nil' do
+      let(:override_options) { { max_threads: nil } }
+
+      it 'does not set it' do
+        subject.should_not_receive(:max_threads=)
+      end
+    end
+
+    context 'when an option is no allowed' do
+      let(:override_options) { { not_allowed: 'owned' } }
+
+      it 'does not set it' do
+        subject.should_not_receive(:not_allowed=)
+      end
+    end
+
+    context 'when valid option' do
+      let(:override_options) { { max_threads: 30 } }
+
+      it 'sets it' do
+        subject.should_receive(:max_threads=).with(30)
+      end
+    end
+
+    context 'when multiple options' do
+      let(:override_options) {
+        { max_threads: 10, not_allowed: 'owned', proxy: 'host:port' }
+      }
+
+      it 'sets @max_threads, @proxy' do
+        subject.should_not_receive(:not_allowed=)
+        subject.should_receive(:max_threads=).with(10)
+        subject.should_receive(:proxy=).with('host:port')
+      end
+    end
   end
 
 end