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+              GNU GENERAL PUBLIC LICENSE
+                Version 3, 29 June 2007
+
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+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+              END OF TERMS AND CONDITIONS
+
+     How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/common/Setup.hs b/common/Setup.hs
new file mode 100644
index 0000000..9a994af
--- /dev/null
+++ b/common/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/common/common.cabal b/common/common.cabal
new file mode 100644
index 0000000..e072acf
--- /dev/null
+++ b/common/common.cabal
@@ -0,0 +1,41 @@
+name:                common
+version:             0.0.1
+license:             GPL-3
+license-file:        LICENSE
+author:              Joris Guyonvarch
+maintainer:          joris@guyonvarch.me
+category:            Web
+build-type:          Simple
+cabal-version:       >=1.10
+
+library
+  ghc-options:         -Wall -Werror
+  exposed-modules:     Common.Message
+                     , Common.Message.Key
+                     , Common.Model
+                     , Common.Util.Text
+                     , Common.View.Format
+  other-modules:       Common.Message.Lang
+                     , Common.Message.Translation
+                     , Common.Model.PaymentCategory
+                     , Common.Model.CreateCategory
+                     , Common.Model.CreatePayment
+                     , Common.Model.CreateIncome
+                     , Common.Model.EditCategory
+                     , Common.Model.EditPayment
+                     , Common.Model.InitResult
+                     , Common.Model.EditIncome
+                     , Common.Model.Frequency
+                     , Common.Model.Currency
+                     , Common.Model.Category
+                     , Common.Model.Payment
+                     , Common.Model.Income
+                     , Common.Model.SignIn
+                     , Common.Model.Init
+                     , Common.Model.User
+  build-depends:       aeson
+                     , base >=4.9 && <4.11
+                     , text
+                     , time
+  hs-source-dirs:      src
+  default-language:    Haskell2010
diff --git a/common/src/Common/Message.hs b/common/src/Common/Message.hs
new file mode 100644
index 0000000..9ae735d
--- /dev/null
+++ b/common/src/Common/Message.hs
@@ -0,0 +1,12 @@
+module Common.Message
+  ( get
+  ) where
+
+import Data.Text (Text)
+
+import Common.Message.Key (Key)
+import Common.Message.Lang (Lang(..))
+import qualified Common.Message.Translation as Translation
+
+get :: Key -> Text
+get = Translation.get French
diff --git a/common/src/Common/Message/Key.hs b/common/src/Common/Message/Key.hs
new file mode 100644
index 0000000..4127808
--- /dev/null
+++ b/common/src/Common/Message/Key.hs
@@ -0,0 +1,152 @@
+module Common.Message.Key
+  ( Key(..)
+  ) where
+
+import Data.Text
+
+data Key =
+
+  App_Title
+
+  | Category_Add
+  | Category_Clone
+  | Category_Color
+  | Category_DeleteConfirm
+  | Category_Edit
+  | Category_Empty
+  | Category_Name
+  | Category_NotDeleted
+  | Category_Title
+  | Category_Used
+
+  | Date_Long Int Text Int
+  | Date_Short Int Int Int
+  | Date_ShortMonthAndYear Int Int
+
+  | Dialog_Confirm
+  | Dialog_Undo
+
+  | Error_CategoryCreate
+  | Error_CategoryDelete
+  | Error_CategoryEdit
+  | Error_IncomeCreate
+  | Error_IncomeDelete
+  | Error_IncomeEdit
+  | Error_PaymentCreate
+  | Error_PaymentDelete
+  | Error_PaymentEdit
+  | Error_SignOut
+
+  | Form_AlreadyExists
+  | Form_CostMustNotBeNull
+  | Form_Empty
+  | Form_GreaterIntThan Int
+  | Form_InvalidCategory
+  | Form_InvalidColor
+  | Form_InvalidDate
+  | Form_InvalidInt
+  | Form_InvalidString
+  | Form_SmallerIntThan Int
+
+  | HttpError_BadPayload
+  | HttpError_BadUrl
+  | HttpError_NetworkError
+  | HttpError_Timeout
+
+  | Income_AddLong
+  | Income_AddShort
+  | Income_Amount
+  | Income_Clone
+  | Income_CumulativeSince Text
+  | Income_Date
+  | Income_DeleteConfirm
+  | Income_Edit
+  | Income_Empty
+  | Income_MonthlyNet
+  | Income_NotDeleted
+  | Income_Title
+
+  | Month_January
+  | Month_February
+  | Month_March
+  | Month_April
+  | Month_May
+  | Month_June
+  | Month_July
+  | Month_August
+  | Month_September
+  | Month_October
+  | Month_November
+  | Month_December
+
+  | PageNotFound_Title
+
+  | Payment_Add
+  | Payment_Balanced
+  | Payment_Category
+  | Payment_CloneLong
+  | Payment_CloneShort
+  | Payment_Cost
+  | Payment_Date
+  | Payment_Delete
+  | Payment_DeleteConfirm
+  | Payment_EditLong
+  | Payment_EditShort
+  | Payment_Empty
+  | Payment_Frequency
+  | Payment_InvalidFrequency
+  | Payment_Many
+  | Payment_MonthlyFemale
+  | Payment_MonthlyMale
+  | Payment_Name
+  | Payment_NotDeleted
+  | Payment_One
+  | Payment_PunctualFemale
+  | Payment_PunctualMale
+  | Payment_Title
+  | Payment_User
+  | Payment_Worth Text Text
+
+  | Search_Monthly
+  | Search_Name
+  | Search_Punctual
+
+  | Secure_Forbidden
+  | Secure_Unauthorized
+
+  | SignIn_Button
+  | SignIn_DisconnectSuccess
+  | SignIn_EmailInvalid
+  | SignIn_EmailPlaceholder
+  | SignIn_EmailSendFail
+  | SignIn_EmailSent
+  | SignIn_LinkExpired
+  | SignIn_LinkInvalid
+  | SignIn_LinkUsed
+  | SignIn_MailTitle
+  | SignIn_MailBody Text Text
+  | SignIn_ParseError
+
+  | Statistic_Title
+  | Statistic_ByMonthsAndMean Text
+  | Statistic_By Text Text
+  | Statistic_Total
+
+  | WeeklyReport_Empty
+  | WeeklyReport_IncomesCreated Int
+  | WeeklyReport_IncomesDeleted Int
+  | WeeklyReport_IncomesEdited Int
+  | WeeklyReport_IncomeCreated Int
+  | WeeklyReport_IncomeDeleted Int
+  | WeeklyReport_IncomeEdited Int
+  | WeeklyReport_PayedFor Text Text Text Text
+  | WeeklyReport_PayedForNot Text Text Text Text
+  | WeeklyReport_PayedFrom Text Text Text
+  | WeeklyReport_PayedFromNot Text Text Text
+  | WeeklyReport_PaymentsCreated Int
+  | WeeklyReport_PaymentsDeleted Int
+  | WeeklyReport_PaymentsEdited Int
+  | WeeklyReport_PaymentCreated Int
+  | WeeklyReport_PaymentDeleted Int
+  | WeeklyReport_PaymentEdited Int
+  | WeeklyReport_Title
diff --git a/common/src/Common/Message/Lang.hs b/common/src/Common/Message/Lang.hs
new file mode 100644
index 0000000..0a32ede
--- /dev/null
+++ b/common/src/Common/Message/Lang.hs
@@ -0,0 +1,7 @@
+module Common.Message.Lang
+  ( Lang(..)
+  ) where
+
+data Lang =
+  English
+  | French
diff --git a/common/src/Common/Message/Translation.hs b/common/src/Common/Message/Translation.hs
new file mode 100644
index 0000000..900a9e9
--- /dev/null
+++ b/common/src/Common/Message/Translation.hs
@@ -0,0 +1,697 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Common.Message.Translation
+  ( get
+  ) where
+
+import Data.Text (Text)
+import qualified Data.Text as T
+
+import Common.Message.Key
+import Common.Message.Lang (Lang(..))
+
+get :: Lang -> Key -> Text
+get = m
+
+m :: Lang -> Key -> Text
+
+m l App_Title =
+  case l of
+    English -> "Shared Cost"
+    French  -> "Partage des frais"
+
+m l Category_Add =
+  case l of
+    English -> "Add an category"
+    French  -> "Ajouter une catégorie"
+
+m l Category_Clone =
+  case l of
+    English -> "Clone an category"
+    French  -> "Cloner une catégorie"
+
+m l Category_Color =
+  case l of
+    English -> "Color"
+    French  -> "Couleur"
+
+m l Category_DeleteConfirm =
+  case l of
+    English -> "Are you sure to delete this category ?"
+    French  -> "Voulez-vous vraiment supprimer cette catégorie ?"
+
+m l Category_Edit =
+  case l of
+    English -> "Edit an category"
+    French  -> "Modifier une catégorie"
+
+m l Category_Empty =
+  case l of
+    English -> "No category."
+    French  -> "Aucune catégorie."
+
+m l Category_Name =
+  case l of
+    English -> "Name"
+    French  -> "Nom"
+
+m l Category_NotDeleted =
+  case l of
+    English -> "The category could not have been deleted."
+    French  -> "La catégorie n’a pas pu être supprimé."
+
+m l Category_Title =
+  case l of
+    English -> "Categories"
+    French  -> "Catégories"
+
+m l Category_Used =
+  case l of
+    English -> "This category is currently being used"
+    French  -> "Cette catégorie est actuellement utilisée"
+
+m l (Date_Short day month year) =
+  case l of
+    English ->
+      T.intercalate "-" [ padded year 4, padded month 2, padded day 2 ]
+    French ->
+      T.intercalate "/" [ padded day 2, padded month 2, padded year 4 ]
+  where padded num pad =
+          let str = show num
+          in  T.pack $ replicate (pad - length str) '0' ++ str
+
+m l (Date_ShortMonthAndYear month year) =
+  case l of
+    English ->
+      T.intercalate "-" . map (T.pack . show) $ [ year, month ]
+    French ->
+      T.intercalate "/" . map (T.pack . show) $ [ month, year ]
+
+m l (Date_Long day month year) =
+  case l of
+    English ->
+      T.concat [ month, " " , T.pack . show $ day, ", ", T.pack . show $ year ]
+    French ->
+      T.intercalate " " [ T.pack . show $ day, month, T.pack . show $ year ]
+
+m l Dialog_Confirm =
+  case l of
+    English -> "Confirm"
+    French  -> "Confirmer"
+
+m l Dialog_Undo =
+  case l of
+    English -> "Undo"
+    French  -> "Annuler"
+
+m l Error_CategoryCreate =
+  case l of
+    English -> "Error at category creation"
+    French  -> "Erreur lors de la création de la catégorie"
+
+m l Error_CategoryDelete =
+  case l of
+    English -> "Error at category deletion"
+    French  -> "Erreur lors de la suppression de la catégorie"
+
+m l Error_CategoryEdit =
+  case l of
+    English -> "Error at category edition"
+    French  -> "Erreur lors de la modification de la catégorie"
+
+m l Error_IncomeCreate =
+  case l of
+    English -> "Error at income creation"
+    French  -> "Erreur lors de la création du revenu"
+
+m l Error_IncomeDelete =
+  case l of
+    English -> "Error at income deletion"
+    French  -> "Erreur lors de la suppression du revenu"
+
+m l Error_IncomeEdit =
+  case l of
+    English -> "Error at income edition"
+    French  -> "Erreur lors de la modification du revenu"
+
+m l Error_PaymentCreate =
+  case l of
+    English -> "Error at payment creation"
+    French  -> "Erreur lors de la création du paiement"
+
+m l Error_PaymentDelete =
+  case l of
+    English -> "Error at payment deletion"
+    French  -> "Erreur lors de la suppression du paiement"
+
+m l Error_PaymentEdit =
+  case l of
+    English -> "Error at payment edition"
+    French  -> "Erreur lors de la modification du paiement"
+
+m l Error_SignOut =
+  case l of
+    English -> "Error at sign out"
+    French  -> "Erreur lors de la déconnexion"
+
+m l Form_AlreadyExists =
+  case l of
+    English -> "Dupplicate field"
+    French  -> "Doublon"
+
+m l Form_CostMustNotBeNull =
+  case l of
+    English -> "Cost must not be zero"
+    French -> "Le coût ne doît pas être nul"
+
+m l Form_Empty =
+  case l of
+    English -> "Required field"
+    French  -> "Champ requis"
+
+m l (Form_GreaterIntThan number) =
+  case l of
+    English -> T.concat [ "Integer smaller than ", T.pack . show $ number, " or equal required" ]
+    French  -> T.concat [ "Entier inférieur ou égal à ", T.pack . show $ number, " requis" ]
+
+m l Form_InvalidCategory =
+  case l of
+    English -> "Invalid category"
+    French  -> "Catégorie invalide"
+
+m l Form_InvalidColor =
+  case l of
+    English -> "Invalid color"
+    French  -> "Couleur invalide"
+
+m l Form_InvalidDate =
+  case l of
+    English -> "day/month/year required"
+    French  -> "jour/mois/année requis"
+
+m l Form_InvalidInt =
+  case l of
+    English -> "Integer required"
+    French  -> "Entier requis"
+
+m l Form_InvalidString =
+  case l of
+    English -> "String required"
+    French  -> "Chaîne de caractères requise"
+
+m l (Form_SmallerIntThan number) =
+  case l of
+    English -> T.concat [ "Integer bigger than ", T.pack . show $ number, " or equal required" ]
+    French  -> T.concat [ "Entier supérieur ou égal à ", T.pack . show $ number, " requis" ]
+
+m l HttpError_BadPayload =
+  case l of
+    English -> "Bad payload server error"
+    French  -> "Contenu inattendu en provenance du serveur"
+
+m l HttpError_BadUrl =
+  case l of
+    English -> "URL not valid"
+    French  -> "l’URL n’est pas valide"
+
+m l HttpError_NetworkError =
+  case l of
+    English -> "Network can not be reached"
+    French  -> "Le serveur n’est pas accessible"
+
+m l HttpError_Timeout =
+  case l of
+    English -> "Timeout server error"
+    French  -> "Le serveur met trop de temps à répondre"
+
+m l Income_AddLong =
+  case l of
+    English -> "Add an income"
+    French  -> "Ajouter un revenu"
+
+m l Income_AddShort =
+  case l of
+    English -> "Add"
+    French  -> "Ajouter"
+
+m l Income_Amount =
+  case l of
+    English -> "Amount"
+    French  -> "Montant"
+
+m l Income_Clone =
+  case l of
+    English -> "Clone an income"
+    French  -> "Cloner un revenu"
+
+m l (Income_CumulativeSince since) =
+  case l of
+    English -> T.concat [ "Cumulative incomes since ", since ]
+    French  -> T.concat [ "Revenus nets cumulés depuis le ", since ]
+
+m l Income_Date =
+  case l of
+    English -> "Date"
+    French  -> "Date"
+
+m l Income_DeleteConfirm =
+  case l of
+    English -> "Are you sure to delete this income ?"
+    French  -> "Voulez-vous vraiment supprimer ce revenu ?"
+
+m l Income_Edit =
+  case l of
+    English -> "Edit an income"
+    French  -> "Modifier un revenu"
+
+m l Income_Empty =
+  case l of
+    English -> "No income."
+    French  -> "Aucun revenu."
+
+m l Income_MonthlyNet =
+  case l of
+    English -> "Net monthly incomes"
+    French  -> "Revenus mensuels nets"
+
+m l Income_NotDeleted =
+  case l of
+    English -> "The income could not have been deleted."
+    French  -> "Le revenu n’a pas pu être supprimé."
+
+m l Income_Title =
+  case l of
+    English -> "Income"
+    French  -> "Revenu"
+
+m l Month_January =
+  case l of
+    English -> "january"
+    French  -> "janvier"
+
+m l Month_February =
+  case l of
+    English -> "february"
+    French  -> "février"
+
+m l Month_March =
+  case l of
+    English -> "march"
+    French  -> "mars"
+
+m l Month_April =
+  case l of
+    English -> "april"
+    French  -> "avril"
+
+m l Month_May =
+  case l of
+    English -> "may"
+    French  -> "mai"
+
+m l Month_June =
+  case l of
+    English -> "june"
+    French  -> "juin"
+
+m l Month_July =
+  case l of
+    English -> "july"
+    French  -> "juillet"
+
+m l Month_August =
+  case l of
+    English -> "august"
+    French  -> "août"
+
+m l Month_September =
+  case l of
+    English -> "september"
+    French  -> "septembre"
+
+m l Month_October =
+  case l of
+    English -> "october"
+    French  -> "octobre"
+
+m l Month_November =
+  case l of
+    English -> "november"
+    French  -> "novembre"
+
+m l Month_December =
+  case l of
+    English -> "december"
+    French  -> "décembre"
+
+m l PageNotFound_Title =
+  case l of
+    English -> "Page not found"
+    French  -> "Page introuvable"
+
+m l Payment_Add =
+  case l of
+    English -> "Add a payment"
+    French  -> "Ajouter un paiement"
+
+m l Payment_Balanced =
+  case l of
+    English -> "Payments are balanced."
+    French  -> "Les paiements sont équilibrés."
+
+m l Payment_Category =
+  case l of
+    English -> "Category"
+    French  -> "Catégorie"
+
+m l Payment_CloneLong =
+  case l of
+    English -> "Clone a payment"
+    French  -> "Cloner un paiement"
+
+m l Payment_CloneShort =
+  case l of
+    English -> "Clone"
+    French  -> "Cloner"
+
+m l Payment_Cost =
+  case l of
+    English -> "Cost"
+    French  -> "Coût"
+
+m l Payment_Date =
+  case l of
+    English -> "Date"
+    French  -> "Date"
+
+m l Payment_Delete =
+  case l of
+    English -> "Delete"
+    French  -> "Supprimer"
+
+m l Payment_DeleteConfirm =
+  case l of
+    English -> "Are you sure to delete this payment ?"
+    French  -> "Voulez-vous vraiment supprimer ce paiement ?"
+
+m l Payment_EditLong =
+  case l of
+    English -> "Edit a payment"
+    French  -> "Modifier un paiement"
+
+m l Payment_EditShort =
+  case l of
+    English -> "Edit"
+    French  -> "Modifier"
+
+m l Payment_Empty =
+  case l of
+    English -> "No payment found from your search criteria."
+    French  -> "Aucun paiement ne correspond à vos critères de recherches."
+
+m l Payment_Frequency =
+  case l of
+    English -> "Frequency"
+    French  -> "Fréquence"
+
+m l Payment_InvalidFrequency =
+  case l of
+    English -> "Invalid frequency"
+    French  -> "Fréquence invalide"
+
+m l Payment_Many =
+  case l of
+    English -> "payments"
+    French  -> "paiements"
+
+m l Payment_MonthlyFemale =
+  case l of
+    English -> "Monthly"
+    French  -> "Mensuelle"
+
+m l Payment_MonthlyMale =
+  case l of
+    English -> "Monthly"
+    French  -> "Mensuel"
+
+m l Payment_Name =
+  case l of
+    English -> "Name"
+    French  -> "Nom"
+
+m l Payment_NotDeleted =
+  case l of
+    English -> "The payment could not have been deleted."
+    French  -> "Le paiement n’a pas pu être supprimé."
+
+m l Payment_One =
+  case l of
+    English -> "payment"
+    French  -> "paiement"
+
+m l Payment_PunctualFemale =
+  case l of
+    English -> "Punctual"
+    French  -> "Ponctuelle"
+
+m l Payment_PunctualMale =
+  case l of
+    English -> "Punctual"
+    French  -> "Ponctuel"
+
+m l Payment_Title =
+  case l of
+    English -> "Payments"
+    French -> "Paiements"
+
+m l Payment_User =
+  case l of
+    English -> "Payer"
+    French  -> "Payeur"
+
+m l (Payment_Worth subject amount) =
+  case l of
+    English -> T.concat [ subject, " worth ", amount ]
+    French -> T.concat [ subject, " comptabilisant ", amount ]
+
+m l Search_Monthly =
+  case l of
+    English -> "Monthly"
+    French  -> "Mensuel"
+
+m l Search_Name =
+  case l of
+    English -> "Search"
+    French  -> "Recherche"
+
+m l Search_Punctual =
+  case l of
+    English -> "Punctual"
+    French  -> "Ponctuel"
+
+m l Secure_Unauthorized =
+  case l of
+    English -> "You are not authorized to sign in."
+    French  -> "Tu n’es pas autorisé à te connecter."
+
+m l Secure_Forbidden =
+  case l of
+    English -> "You need to be logged in to perform this action"
+    French  -> "Tu dois te connecter pour effectuer cette action"
+
+m l SignIn_Button =
+  case l of
+    English -> "Sign in"
+    French  -> "Connexion"
+
+m l SignIn_DisconnectSuccess =
+  case l of
+    English -> "You have successfully disconnected"
+    French  -> "Vous êtes à présent déconnecté."
+
+m l SignIn_EmailInvalid =
+  case l of
+    English -> "Your email is not valid."
+    French  -> "Votre courriel n’est pas valide."
+
+m l SignIn_EmailPlaceholder =
+  case l of
+    English -> "Email"
+    French -> "Courriel"
+
+m l SignIn_EmailSendFail =
+  case l of
+    English -> "You are authorized to sign in, but we failed to send you the sign up email."
+    French  -> "Tu es autorisé à te connecter, mais nous n’avons pas pu t’envoyer le courriel de connexion."
+
+m l SignIn_EmailSent =
+  case l of
+    English -> "We sent you an email with a connexion link."
+    French  -> "Nous t’avons envoyé un courriel avec un lien pour te connecter."
+
+m l SignIn_LinkExpired =
+  case l of
+    English -> "The link expired, please sign in again."
+    French  -> "Le lien sur lequel tu as cliqué a expiré, connecte-toi à nouveau."
+
+m l SignIn_LinkInvalid =
+  case l of
+    English -> "The link is invalid, please sign in again."
+    French  -> "Le lien sur lequel tu as cliqué est invalide, connecte-toi à nouveau."
+
+m l SignIn_LinkUsed =
+  case l of
+    English -> "You already used this link, please sign in again."
+    French  -> "Tu as déjà utilisé ce lien, connecte-toi à nouveau."
+
+m l SignIn_MailTitle =
+  case l of
+    English -> T.concat [ "Sign in to ", m l App_Title ]
+    French  -> T.concat [ "Connexion à ", m l App_Title ]
+
+m l (SignIn_MailBody name url) =
+  T.intercalate
+    "\n"
+    ( case l of
+        English ->
+          [ T.concat [ "Hi ", name, "," ]
+          , ""
+          , T.concat
+              [ "Click to the following link in order to sign in to Shared Cost:"
+              , m l App_Title
+              , ":"
+              ]
+          , url
+          , ""
+          , "See you soon!"
+          ]
+        French  ->
+          [ T.concat [ "Salut ", name, "," ]
+          , ""
+          , T.concat
+              [ "Clique sur le lien suivant pour te connecter à "
+              , m l App_Title
+              , ":"
+              ]
+          , url
+          , ""
+          , "À très vite !"
+          ]
+    )
+
+m l SignIn_ParseError =
+  case l of
+    English -> "Error while reading initial data."
+    French  -> "Erreur lors de la lecture des données initiales."
+
+m l (Statistic_By key value) =
+  case l of
+    English -> T.concat [ key, ": ", value ]
+    French  -> T.concat [ key, " : ", value ]
+
+m l (Statistic_ByMonthsAndMean amount) =
+  case l of
+    English ->
+      T.concat [ "Payments by category by month months (", amount, "on average)" ]
+    French  ->
+      T.concat [ "Paiements par catégorie par mois (en moyenne ", amount, ")" ]
+
+m l Statistic_Title =
+  case l of
+    English -> "Statistics"
+    French  -> "Statistiques"
+
+m l Statistic_Total =
+  case l of
+    English -> "Total"
+    French  -> "Total"
+
+m l WeeklyReport_Empty =
+  case l of
+    English -> "No activity the previous week."
+    French  -> "Pas d’activité la semaine passée."
+
+m l (WeeklyReport_IncomesCreated count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " incomes created:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenus créés :" ]
+
+m l (WeeklyReport_IncomesDeleted count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " incomes deleted:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenus supprimés :" ]
+
+m l (WeeklyReport_IncomesEdited count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " incomes edited:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenus modifiés :" ]
+
+m l (WeeklyReport_IncomeCreated count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " income created:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenu créé :" ]
+
+m l (WeeklyReport_IncomeDeleted count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " income deleted:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenu supprimé :" ]
+
+m l (WeeklyReport_IncomeEdited count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " income edited:" ]
+    French  -> T.concat [ T.pack . show $ count, " revenu modifié :" ]
+
+m l (WeeklyReport_PayedFor name amount for at) =
+  case l of
+    English -> T.concat [ T.pack . show $ name, " payed ", amount, " for “", for, "” at ", at ]
+    French  -> T.concat [ T.pack . show $ name, " a payé ", amount, " concernant « ", for, " » le ", at ]
+
+m l (WeeklyReport_PayedForNot name amount for at) =
+  case l of
+    English -> T.concat [ T.pack . show $ name, " didn’t pay ", amount, " for “", for, "” at ", at ]
+    French  -> T.concat [ T.pack . show $ name, " n’a pas payé ", amount, " concernant « ", for, " » le ", at ]
+
+m l (WeeklyReport_PayedFrom name amount for) =
+  case l of
+    English -> T.concat [ T.pack . show $ name, " is payed ", amount, " of net monthly income from ", for ]
+    French  -> T.concat [ T.pack . show $ name, " est payé ", amount, " net par mois à partir du ", for ]
+
+m l (WeeklyReport_PayedFromNot name amount for) =
+  case l of
+    English -> T.concat [ T.pack . show $ name, " isn’t payed ", amount, " of net monthly income from ", for ]
+    French  -> T.concat [ T.pack . show $ name, " n’est pas payé ", amount, " net par mois à partir du ", for ]
+
+m l (WeeklyReport_PaymentsCreated count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payments created:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiements créés :" ]
+
+m l (WeeklyReport_PaymentsDeleted count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payments deleted:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiements supprimés :" ]
+
+m l (WeeklyReport_PaymentsEdited count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payments edited:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiements modifiés :" ]
+
+m l (WeeklyReport_PaymentCreated count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payment created:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiement créé :" ]
+
+m l (WeeklyReport_PaymentDeleted count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payment deleted:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiement supprimé :" ]
+
+m l (WeeklyReport_PaymentEdited count) =
+  case l of
+    English -> T.concat [ T.pack . show $ count, " payment edited:" ]
+    French  -> T.concat [ T.pack . show $ count, " paiement modifié :" ]
+
+m l WeeklyReport_Title =
+  case l of
+    English -> "Weekly report"
+    French  -> "Rapport hebdomadaire"
diff --git a/common/src/Common/Model.hs b/common/src/Common/Model.hs
new file mode 100644
index 0000000..80c344b
--- /dev/null
+++ b/common/src/Common/Model.hs
@@ -0,0 +1,18 @@
+module Common.Model (module X) where
+
+import Common.Model.Category as X
+import Common.Model.CreateCategory as X
+import Common.Model.CreateIncome as X
+import Common.Model.CreatePayment as X
+import Common.Model.Currency as X
+import Common.Model.EditCategory as X
+import Common.Model.EditIncome as X
+import Common.Model.EditPayment as X
+import Common.Model.Frequency as X
+import Common.Model.Income as X
+import Common.Model.Init as X
+import Common.Model.InitResult as X
+import Common.Model.Payment as X
+import Common.Model.PaymentCategory as X
+import Common.Model.SignIn as X
+import Common.Model.User as X
diff --git a/common/src/Common/Model/Category.hs b/common/src/Common/Model/Category.hs
new file mode 100644
index 0000000..53a6bdb
--- /dev/null
+++ b/common/src/Common/Model/Category.hs
@@ -0,0 +1,26 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Category
+  ( CategoryId
+  , Category(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Int (Int64)
+import Data.Text (Text)
+import Data.Time (UTCTime)
+import GHC.Generics (Generic)
+
+type CategoryId = Int64
+
+data Category = Category
+  { _category_id :: CategoryId
+  , _category_name :: Text
+  , _category_color :: Text
+  , _category_createdAt :: UTCTime
+  , _category_editedAt :: Maybe UTCTime
+  , _category_deletedAt :: Maybe UTCTime
+  } deriving (Show, Generic)
+
+instance FromJSON Category
+instance ToJSON Category
diff --git a/common/src/Common/Model/CreateCategory.hs b/common/src/Common/Model/CreateCategory.hs
new file mode 100644
index 0000000..bfe24c5
--- /dev/null
+++ b/common/src/Common/Model/CreateCategory.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.CreateCategory
+  ( CreateCategory(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Text (Text)
+import GHC.Generics (Generic)
+
+data CreateCategory = CreateCategory
+  { _createCategory_name :: Text
+  , _createCategory_color :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON CreateCategory
diff --git a/common/src/Common/Model/CreateIncome.hs b/common/src/Common/Model/CreateIncome.hs
new file mode 100644
index 0000000..4ee3a50
--- /dev/null
+++ b/common/src/Common/Model/CreateIncome.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.CreateIncome
+  ( CreateIncome(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+data CreateIncome = CreateIncome
+  { _createIncome_date :: Day
+  , _createIncome_amount :: Int
+  } deriving (Show, Generic)
+
+instance FromJSON CreateIncome
diff --git a/common/src/Common/Model/CreatePayment.hs b/common/src/Common/Model/CreatePayment.hs
new file mode 100644
index 0000000..b5b6256
--- /dev/null
+++ b/common/src/Common/Model/CreatePayment.hs
@@ -0,0 +1,23 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.CreatePayment
+  ( CreatePayment(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Text (Text)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+import Common.Model.Category (CategoryId)
+import Common.Model.Frequency (Frequency)
+
+data CreatePayment = CreatePayment
+  { _createPayment_name :: Text
+  , _createPayment_cost :: Int
+  , _createPayment_date :: Day
+  , _createPayment_category :: CategoryId
+  , _createPayment_frequency :: Frequency
+  } deriving (Show, Generic)
+
+instance FromJSON CreatePayment
diff --git a/common/src/Common/Model/Currency.hs b/common/src/Common/Model/Currency.hs
new file mode 100644
index 0000000..7c12545
--- /dev/null
+++ b/common/src/Common/Model/Currency.hs
@@ -0,0 +1,14 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Currency
+  ( Currency(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Text (Text)
+import GHC.Generics (Generic)
+
+newtype Currency = Currency Text deriving (Show, Generic)
+
+instance FromJSON Currency
+instance ToJSON Currency
diff --git a/common/src/Common/Model/EditCategory.hs b/common/src/Common/Model/EditCategory.hs
new file mode 100644
index 0000000..2a3a697
--- /dev/null
+++ b/common/src/Common/Model/EditCategory.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.EditCategory
+  ( EditCategory(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Text (Text)
+import GHC.Generics (Generic)
+
+import Common.Model.Category (CategoryId)
+
+data EditCategory = EditCategory
+  { _editCategory_id :: CategoryId
+  , _editCategory_name :: Text
+  , _editCategory_color :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON EditCategory
diff --git a/common/src/Common/Model/EditIncome.hs b/common/src/Common/Model/EditIncome.hs
new file mode 100644
index 0000000..a55c39e
--- /dev/null
+++ b/common/src/Common/Model/EditIncome.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.EditIncome
+  ( EditIncome(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+import Common.Model.Income (IncomeId)
+
+data EditIncome = EditIncome
+  { _editIncome_id :: IncomeId
+  , _editIncome_date :: Day
+  , _editIncome_amount :: Int
+  } deriving (Show, Generic)
+
+instance FromJSON EditIncome
diff --git a/common/src/Common/Model/EditPayment.hs b/common/src/Common/Model/EditPayment.hs
new file mode 100644
index 0000000..172c0c1
--- /dev/null
+++ b/common/src/Common/Model/EditPayment.hs
@@ -0,0 +1,25 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.EditPayment
+  ( EditPayment(..)
+  ) where
+
+import Data.Aeson (FromJSON)
+import Data.Text (Text)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+import Common.Model.Category (CategoryId)
+import Common.Model.Frequency (Frequency)
+import Common.Model.Payment (PaymentId)
+
+data EditPayment = EditPayment
+  { _editPayment_id :: PaymentId
+  , _editPayment_name :: Text
+  , _editPayment_cost :: Int
+  , _editPayment_date :: Day
+  , _editPayment_category :: CategoryId
+  , _editPayment_frequency :: Frequency
+  } deriving (Show, Generic)
+
+instance FromJSON EditPayment
diff --git a/common/src/Common/Model/Frequency.hs b/common/src/Common/Model/Frequency.hs
new file mode 100644
index 0000000..7c46605
--- /dev/null
+++ b/common/src/Common/Model/Frequency.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Frequency
+  ( Frequency(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import GHC.Generics (Generic)
+
+data Frequency =
+  Punctual
+  | Monthly
+  deriving (Eq, Read, Show, Generic)
+
+instance FromJSON Frequency
+instance ToJSON Frequency
diff --git a/common/src/Common/Model/Income.hs b/common/src/Common/Model/Income.hs
new file mode 100644
index 0000000..280812f
--- /dev/null
+++ b/common/src/Common/Model/Income.hs
@@ -0,0 +1,29 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Income
+  ( IncomeId
+  , Income(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Int (Int64)
+import Data.Time (UTCTime)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+import Common.Model.User (UserId)
+
+type IncomeId = Int64
+
+data Income = Income
+  { _income_id :: IncomeId
+  , _income_userId :: UserId
+  , _income_date :: Day
+  , _income_amount :: Int
+  , _income_createdAt :: UTCTime
+  , _income_editedAt :: Maybe UTCTime
+  , _income_deletedAt :: Maybe UTCTime
+  } deriving (Show, Generic)
+
+instance FromJSON Income
+instance ToJSON Income
diff --git a/common/src/Common/Model/Init.hs b/common/src/Common/Model/Init.hs
new file mode 100644
index 0000000..68fcfb8
--- /dev/null
+++ b/common/src/Common/Model/Init.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Init
+  ( Init(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import GHC.Generics (Generic)
+
+import Common.Model.Category (Category)
+import Common.Model.Currency (Currency)
+import Common.Model.Income (Income)
+import Common.Model.Payment (Payment)
+import Common.Model.PaymentCategory (PaymentCategory)
+import Common.Model.User (UserId, User)
+
+data Init = Init
+  { _init_users :: [User]
+  , _init_currentUser :: UserId
+  , _init_payments :: [Payment]
+  , _init_incomes :: [Income]
+  , _init_categories :: [Category]
+  , _init_paymentCategories :: [PaymentCategory]
+  , _init_currency :: Currency
+  } deriving (Show, Generic)
+
+instance FromJSON Init
+instance ToJSON Init
diff --git a/common/src/Common/Model/InitResult.hs b/common/src/Common/Model/InitResult.hs
new file mode 100644
index 0000000..43c16f9
--- /dev/null
+++ b/common/src/Common/Model/InitResult.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.InitResult
+  ( InitResult(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Text (Text)
+import GHC.Generics (Generic)
+
+import Common.Model.Init (Init)
+
+data InitResult =
+  InitSuccess Init
+  | InitEmpty (Either Text (Maybe Text))
+  deriving (Show, Generic)
+
+instance FromJSON InitResult
+instance ToJSON InitResult
diff --git a/common/src/Common/Model/Payment.hs b/common/src/Common/Model/Payment.hs
new file mode 100644
index 0000000..804b501
--- /dev/null
+++ b/common/src/Common/Model/Payment.hs
@@ -0,0 +1,33 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.Payment
+  ( PaymentId
+  , Payment(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Int (Int64)
+import Data.Text (Text)
+import Data.Time (UTCTime)
+import Data.Time.Calendar (Day)
+import GHC.Generics (Generic)
+
+import Common.Model.Frequency
+import Common.Model.User (UserId)
+
+type PaymentId = Int64
+
+data Payment = Payment
+  { _payment_id :: PaymentId
+  , _payment_user :: UserId
+  , _payment_name :: Text
+  , _payment_cost :: Int
+  , _payment_date :: Day
+  , _payment_frequency :: Frequency
+  , _payment_createdAt :: UTCTime
+  , _payment_editedAt :: Maybe UTCTime
+  , _payment_deletedAt :: Maybe UTCTime
+  } deriving (Show, Generic)
+
+instance FromJSON Payment
+instance ToJSON Payment
diff --git a/common/src/Common/Model/PaymentCategory.hs b/common/src/Common/Model/PaymentCategory.hs
new file mode 100644
index 0000000..a0e94f9
--- /dev/null
+++ b/common/src/Common/Model/PaymentCategory.hs
@@ -0,0 +1,27 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.PaymentCategory
+  ( PaymentCategoryId
+  , PaymentCategory(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Int (Int64)
+import Data.Text (Text)
+import Data.Time (UTCTime)
+import GHC.Generics (Generic)
+
+import Common.Model.Category (CategoryId)
+
+type PaymentCategoryId = Int64
+
+data PaymentCategory = PaymentCategory
+  { _paymentCategory_id :: PaymentCategoryId
+  , _paymentCategory_name :: Text
+  , _paymentCategory_category :: CategoryId
+  , _paymentCategory_createdAt :: UTCTime
+  , _paymentCategory_editedAt :: Maybe UTCTime
+  } deriving (Show, Generic)
+
+instance FromJSON PaymentCategory
+instance ToJSON PaymentCategory
diff --git a/common/src/Common/Model/SignIn.hs b/common/src/Common/Model/SignIn.hs
new file mode 100644
index 0000000..f4da97f
--- /dev/null
+++ b/common/src/Common/Model/SignIn.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.SignIn
+  ( SignIn(..)
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Text (Text)
+import GHC.Generics (Generic)
+
+data SignIn = SignIn
+  { _signIn_email :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON SignIn
+instance ToJSON SignIn
diff --git a/common/src/Common/Model/User.hs b/common/src/Common/Model/User.hs
new file mode 100644
index 0000000..694c70e
--- /dev/null
+++ b/common/src/Common/Model/User.hs
@@ -0,0 +1,29 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Common.Model.User
+  ( UserId
+  , User(..)
+  , findUser
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import qualified Data.List as L
+import Data.Int (Int64)
+import Data.Text (Text)
+import Data.Time (UTCTime)
+import GHC.Generics (Generic)
+
+type UserId = Int64
+
+data User = User
+  { _user_id :: UserId
+  , _user_creation :: UTCTime
+  , _user_email :: Text
+  , _user_name :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON User
+instance ToJSON User
+
+findUser :: UserId -> [User] -> Maybe User
+findUser userId users = L.find ((== userId) . _user_id) users
diff --git a/common/src/Common/Util/Text.hs b/common/src/Common/Util/Text.hs
new file mode 100644
index 0000000..4af7a4c
--- /dev/null
+++ b/common/src/Common/Util/Text.hs
@@ -0,0 +1,41 @@
+module Common.Util.Text
+  ( unaccent
+  ) where
+
+import Data.Text (Text)
+import qualified Data.Text as T
+
+unaccent :: Text -> Text
+unaccent = T.map unaccentChar
+
+unaccentChar :: Char -> Char
+unaccentChar c = case c of
+  'à' -> 'a'
+  'á' -> 'a'
+  'â' -> 'a'
+  'ã' -> 'a'
+  'ä' -> 'a'
+  'ç' -> 'c'
+  'è' -> 'e'
+  'é' -> 'e'
+  'ê' -> 'e'
+  'ë' -> 'e'
+  'ì' -> 'i'
+  'í' -> 'i'
+  'î' -> 'i'
+  'ï' -> 'i'
+  'ñ' -> 'n'
+  'ò' -> 'o'
+  'ó' -> 'o'
+  'ô' -> 'o'
+  'õ' -> 'o'
+  'ö' -> 'o'
+  'š' -> 's'
+  'ù' -> 'u'
+  'ú' -> 'u'
+  'û' -> 'u'
+  'ü' -> 'u'
+  'ý' -> 'y'
+  'ÿ' -> 'y'
+  'ž' -> 'z'
+  _ -> c
diff --git a/common/src/Common/View/Format.hs b/common/src/Common/View/Format.hs
new file mode 100644
index 0000000..7165965
--- /dev/null
+++ b/common/src/Common/View/Format.hs
@@ -0,0 +1,69 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Common.View.Format
+  ( shortDay
+  , longDay
+  , price
+  , number
+  ) where
+
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.List (intersperse)
+import Data.Maybe (fromMaybe)
+import Data.Time.Calendar (Day, toGregorian)
+
+import qualified Common.Message as Message
+import qualified Common.Message.Key as Key
+import Common.Model (Currency(..))
+
+shortDay :: Day -> Text
+shortDay date =
+  Message.get $ Key.Date_Short
+    day
+    month
+    (fromIntegral year)
+  where (year, month, day) = toGregorian date
+
+longDay :: Day -> Text
+longDay date =
+  Message.get $ Key.Date_Long
+    day
+    (fromMaybe "−" . fmap Message.get . monthToKey $ month)
+    (fromIntegral year)
+  where (year, month, day) = toGregorian date
+
+        monthToKey 1  = Just Key.Month_January
+        monthToKey 2  = Just Key.Month_February
+        monthToKey 3  = Just Key.Month_March
+        monthToKey 4  = Just Key.Month_April
+        monthToKey 5  = Just Key.Month_May
+        monthToKey 6  = Just Key.Month_June
+        monthToKey 7  = Just Key.Month_July
+        monthToKey 8  = Just Key.Month_August
+        monthToKey 9  = Just Key.Month_September
+        monthToKey 10 = Just Key.Month_October
+        monthToKey 11 = Just Key.Month_November
+        monthToKey 12 = Just Key.Month_December
+        monthToKey _ = Nothing
+
+price :: Currency -> Int -> Text
+price (Currency currency) amount = T.concat [ number amount, " ", currency ]
+
+number :: Int -> Text
+number n =
+  T.pack
+  . (++) (if n < 0 then "-" else "")
+  . reverse
+  . concat
+  . intersperse " "
+  . group 3
+  . reverse
+  . show
+  . abs $ n
+
+group :: Int -> [a] -> [[a]]
+group n xs =
+  if length xs <= n
+    then [xs]
+    else (take n xs) : (group n (drop n xs))