diff --git a/shard.yml b/shard.yml
index 742cf0c..ea686c1 100644
--- a/shard.yml
+++ b/shard.yml
@@ -14,6 +14,10 @@ dependencies:
     git: https://git.baguette.netlib.re/Baguette/dodb.cr
   authd:
     git: https://github.com/Lukc/authd
+  weird-crystal-base:
+    git: https://git.baguette.netlib.re/Baguette/weird-crystal-base
+    branch: master
+
 
 targets:
     common-tests:
diff --git a/src/common/requests/download.cr b/src/common/requests/download.cr
index e200a0e..faf2415 100644
--- a/src/common/requests/download.cr
+++ b/src/common/requests/download.cr
@@ -10,7 +10,7 @@ class FileStorage::Request
 		end
 
 		def handle(filestoraged : FileStorage::Service, event : IPC::Event::Events)
-			user = altideald.get_logged_user event
+			user = filestoraged.get_logged_user event
 
 			raise Exception.new "unauthorized" if user.nil?
 
@@ -19,7 +19,7 @@ class FileStorage::Request
 
 			user_data = filestoraged.get_user_data user.uid
 
-			filestoraged.storage.download self, event
+			filestoraged.storage.download self, user_data
 		rescue e
 			return Response::Error.new @mid, "unauthorized"
 		end
diff --git a/src/common/requests/login.cr b/src/common/requests/login.cr
index c1d1e98..76f476c 100644
--- a/src/common/requests/login.cr
+++ b/src/common/requests/login.cr
@@ -26,7 +26,7 @@ class FileStorage::Request
 
 			return Response::Login.new @mid
 		rescue e
-			return Response::Error.new "unauthorized"
+			return Response::Error.new @mid, "unauthorized"
 		end
 	end
 	FileStorage.requests << Login
diff --git a/src/common/requests/transfer.cr b/src/common/requests/transfer.cr
index a309aba..46a7fbf 100644
--- a/src/common/requests/transfer.cr
+++ b/src/common/requests/transfer.cr
@@ -2,6 +2,10 @@ class FileStorage::Request
 	JSONIPC.request Transfer, 40 do
 		property mid        : String   # autogenerated
 		property filedigest : String   # SHA256 digest of the entire file
+		# Chunk:
+		# - n      : Int32  => chunk number
+		# - on     : Int32  => number of chunks
+		# - digest : String => 1024-byte data in base64 format
 		property chunk      : Chunk    # For now, just the counter in a string
 		property data       : String   # base64 slice
 		def initialize(file_info : FileInfo, count, bindata)
@@ -14,7 +18,7 @@ class FileStorage::Request
 		end
 
 		def handle(filestoraged : FileStorage::Service, event : IPC::Event::Events)
-			user = altideald.get_logged_user event
+			user = filestoraged.get_logged_user event
 
 			raise Exception.new "unauthorized" if user.nil?
 
@@ -23,7 +27,7 @@ class FileStorage::Request
 
 			user_data = filestoraged.get_user_data user.uid
 
-			filestoraged.storage.transfer self, event
+			filestoraged.storage.transfer self, user_data
 		rescue e
 			return Response::Error.new @mid, "unauthorized"
 		end
diff --git a/src/common/requests/upload.cr b/src/common/requests/upload.cr
index 8ac2758..eff012f 100644
--- a/src/common/requests/upload.cr
+++ b/src/common/requests/upload.cr
@@ -8,7 +8,7 @@ class FileStorage::Request
 		end
 
 		def handle(filestoraged : FileStorage::Service, event : IPC::Event::Events)
-			user = altideald.get_logged_user event
+			user = filestoraged.get_logged_user event
 
 			raise Exception.new "unauthorized" if user.nil?
 
@@ -17,7 +17,7 @@ class FileStorage::Request
 
 			user_data = filestoraged.get_user_data user.uid
 
-			filestoraged.storage.upload self, event
+			filestoraged.storage.upload self, user_data
 		rescue e
 			return Response::Error.new @mid, "unauthorized"
 		end
@@ -49,15 +49,13 @@ class FileStorage::Response
 		end
 	end
 
-	JSONIPC.request Responses, 100 do
-		include JSON::Serializable
-
-		property mid       : String
-		property responses : Array(Response)   # a response for each request
-		property response  : String
-		property reason    : String?
-
-		def initialize(@mid, @response, @responses, @reason = nil)
-		end
-	end
+#	JSONIPC.request Responses, 100 do
+#		property mid       : String
+#		property responses : Array(Response)   # a response for each request
+#		property response  : String
+#		property reason    : String?
+#
+#		def initialize(@mid, @response, @responses, @reason = nil)
+#		end
+#	end
 end
diff --git a/src/server/main.cr b/src/server/main.cr
index 81052e4..74b1d6c 100644
--- a/src/server/main.cr
+++ b/src/server/main.cr
@@ -3,6 +3,10 @@ require "ipc"
 require "json"
 require "authd"
 
+require "colorize"
+
+require "weird-crystal-base"
+
 require "../common/colors"
 # require "../common/filestorage.cr"
 
@@ -42,7 +46,7 @@ class FileStorage::Service < IPC::Service
 
 	# users_status: keep track of the users' status even if they are disconnected,
 	#               allowing the application to handle connection problems.
-	property users_status = Hash(Int32, User).new
+	property users_status : Hash(Int32, UserData) = Hash(Int32, UserData).new
 
 	# Actual storage.
 	getter storage             : FileStorage::Storage
diff --git a/src/server/storage.cr b/src/server/storage.cr
index afea7b9..cb49cc3 100644
--- a/src/server/storage.cr
+++ b/src/server/storage.cr
@@ -6,8 +6,6 @@ require "openssl"
 require "dodb"
 require "base64"
 
-require "../common/utils"
-
 require "./storage/*"
 
 # private function
@@ -35,17 +33,26 @@ class FileStorage::Storage
 	property db_by_owner      : DODB::Partition(TransferInfo)
 	property db_by_tags       : DODB::Tags(TransferInfo)
 
-	def initialize(storage_directory, file_info_directory)
-		@db = DODB::DataBase(TransferInfo).new @file_info_directory
+	# Where to store the data.
+	property root : String
+
+	getter user_data               : DODB::DataBase(UserData)
+	getter user_data_per_user      : DODB::Index(UserData)
+
+	def initialize(@root, file_info_directory)
+		@db = DODB::DataBase(TransferInfo).new file_info_directory
 
 		# Create indexes, partitions and tags objects.
 		@db_by_filedigest   = @db.new_index     "filedigest", &.file_info.digest
 		@db_by_owner        = @db.new_partition "owner",      &.owner.to_s
 		@db_by_tags         = @db.new_tags      "tags",       &.file_info.tags
+
+		@user_data            = DODB::DataBase(UserData).new "#{@root}/user-data"
+		@user_data_per_user   = @user_data.new_index "uid",    &.uid.to_s
 	end
 
 	# Reception of a file chunk.
-	def transfer(message : FileStorage::Transfer, user : User) : FileStorage::Response
+	def transfer(message : FileStorage::Request::Transfer, user : UserData)
 
 		# We received a message containing a chunk of file.
 		mid = message.mid
@@ -78,11 +85,11 @@ class FileStorage::Storage
 		FileStorage::Response::Transfer.new mid
 	rescue e
 		puts "Error handling transfer: #{e.message}"
-		FileStorage::Response.new mid.not_nil!, "Not Ok", "Unexpected error: #{e.message}"
+		FileStorage::Response::Error.new mid.not_nil!, "Unexpected error: #{e.message}"
 	end
 
 	# the client sent an upload request
-	def upload(request : FileStorage::Request::Upload, user : User) : FileStorage::Response
+	def upload(request : FileStorage::Request::Upload, user : UserData)
 
 		mid = request.mid
 		mid ||= "no message id"
@@ -108,12 +115,12 @@ class FileStorage::Storage
 		FileStorage::Response::Upload.new request.mid
 	rescue e
 		puts "Error handling transfer: #{e.message}"
-		FileStorage::Response.new mid.not_nil!, "Not Ok", "Unexpected error: #{e.message}"
+		FileStorage::Response::Error.new mid.not_nil!, "Unexpected error: #{e.message}"
 	end
 
 	# TODO
 	# The client sent a download request.
-	def download(request : FileStorage::DownloadRequest, user : User) : FileStorage::Response
+	def download(request : FileStorage::Request::Download, user : UserData)
 
 		puts "hdl download: mid=#{request.mid}"
 		pp! request
@@ -121,12 +128,11 @@ class FileStorage::Storage
 		FileStorage::Response::Download.new request.mid
 	end
 
-
 	# Entry point for request management
 	# Each request should have a response.
 	# Then, responses are sent in a single message.
 	def requests(requests : Array(FileStorage::Request),
-		user : User,
+		user : UserData,
 		event : IPC::Event::Message) : Array(FileStorage::Response)
 
 		puts "hdl request"
@@ -147,4 +153,50 @@ class FileStorage::Storage
 
 		responses
 	end
+
+	def remove_chunk_from_db(transfer_info : TransferInfo, chunk_number : Int32)
+		transfer_info.chunks.delete chunk_number
+		@db_by_filedigest.update transfer_info.file_info.digest, transfer_info
+	end
+
+	def write_a_chunk(userid : String,
+		file_info : FileStorage::FileInfo,
+		chunk_number : Int32,
+		data : Bytes)
+
+		# storage: @root/files/userid/fileuuid.bin
+		dir = "#{@root}/files/#{userid}"
+
+		FileUtils.mkdir_p dir
+
+		path = "#{dir}/#{file_info.digest}.bin"
+		# Create file if non existant
+		File.open(path, "a+") do |file|
+		end
+
+		# Write in it
+		File.open(path, "ab") do |file|
+			offset = chunk_number * FileStorage.message_buffer_size
+			file.seek(offset, IO::Seek::Set)
+			file.write data
+		end
+	end
 end
+
+###	# TODO:
+###	#   why getting the file_info here? We could check for the transfer_info right away
+###	#   it has more info, and we'll get it later eventually
+###
+###	file_info = nil
+###	begin
+###		file_info = user.uploads.select do |v|
+###			v.file.digest == message.filedigest
+###		end.first.file
+###
+###		pp! file_info
+###	rescue e : IndexError
+###		puts "No recorded upload request for file #{message.filedigest}"
+###
+###	rescue e
+###		puts "Unexpected error: #{e}"
+###	end
diff --git a/src/server/storage/user-data.cr b/src/server/storage/user-data.cr
index 5d8d9ca..6233eba 100644
--- a/src/server/storage/user-data.cr
+++ b/src/server/storage/user-data.cr
@@ -9,13 +9,12 @@ class FileStorage::UserData
 	include JSON::Serializable
 
 	property uid       : Int32
-	property token     : AuthD::User::Public
+	# property token     : AuthD::User::Public?
 	property uploads   : Array(FileStorage::Request::Upload)
 	property downloads : Array(FileStorage::Request::Download)
 
-	def initialize(@token,
+	def initialize(@uid,
 		@uploads   = Array(FileStorage::Request::Upload).new,
 		@downloads = Array(FileStorage::Request::Download).new)
-		@uid = token.uid
 	end
 end