diff --git a/src/configuration/cms_default_setup.e b/src/configuration/cms_default_setup.e
index abffef9..95fc661 100644
--- a/src/configuration/cms_default_setup.e
+++ b/src/configuration/cms_default_setup.e
@@ -134,13 +134,6 @@ feature -- Access
 			end
 		end
 
-	build_auth_engine
-		do
-			to_implement ("Not implemented authentication")
-				-- Note: we can remoce this feature, unless we want to
-				-- provide a custom auth strategy.
-		end
-
 	build_mailer
 		do
 			to_implement ("Not implemented mailer")
diff --git a/src/configuration/cms_setup.e b/src/configuration/cms_setup.e
index a5cd6eb..16fb594 100644
--- a/src/configuration/cms_setup.e
+++ b/src/configuration/cms_setup.e
@@ -106,12 +106,15 @@ feature -- Access: Theme
 feature -- Access: storage
 
 	storage_drivers: STRING_TABLE [CMS_STORAGE_BUILDER]
-			-- table of storage drivers that the cms is aware.
+			-- Table of available storage drivers.
+			-- i.e: mysql, sqlite, ...
 		deferred
 		end
 
 	storage (a_error_handler: ERROR_HANDLER): detachable CMS_STORAGE
-			-- Retrieve current CMS_STORAGE strategy based on a configuration file.
+			-- CMS Storage object defined according to the configuration or default.
+			-- Use `a_error_handler' to get eventual error information occurred during the storage
+			-- initialization.
 		local
 			retried: BOOLEAN
 			l_message: STRING
@@ -126,7 +129,7 @@ feature -- Access: storage
 				end
 			else
 				to_implement ("Workaround code, persistence layer does not implement yet this kind of error handling.")
-					-- error hanling.
+					-- error handling.
 				create l_message.make (1024)
 				if attached ((create {EXCEPTION_MANAGER}).last_exception) as l_exception then
 					if attached l_exception.description as l_description then
diff --git a/src/service/cms_api.e b/src/service/cms_api.e
index 177054b..cbfb7f7 100644
--- a/src/service/cms_api.e
+++ b/src/service/cms_api.e
@@ -35,7 +35,6 @@ feature {NONE} -- Initialize
 		local
 			l_module: CMS_MODULE
 		do
-			to_implement ("Refactor database setup")
 			if attached setup.storage (error_handler) as l_storage then
 				storage := l_storage
 			else
diff --git a/src/service/cms_service.e b/src/service/cms_service.e
index 2b8e06a..af717c0 100644
--- a/src/service/cms_service.e
+++ b/src/service/cms_service.e
@@ -55,7 +55,6 @@ feature {NONE} -- Initialization
 		do
 			initialize_modules
 			initialize_users
-			initialize_auth_engine
 			initialize_mailer
 				-- initialize_router
 				-- initialize_filter: expanded here, for void-safety concern.
@@ -83,11 +82,6 @@ feature {NONE} -- Initialization
 			to_implement ("To Implement mailer")
 		end
 
-	initialize_auth_engine
-		do
-			to_implement ("To Implement authentication engine")
-		end
-
 feature -- Settings: router
 
 	setup_router