diff --git a/LICENSE b/LICENSE
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+++ b/LICENSE
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+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
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+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 Affero 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 Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero 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 your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  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 AGPL, see
+<http://www.gnu.org/licenses/>.
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,21 @@
+# Haskell-bee
+
+A lightweight, type-safe library for implementing asynchronous job workers in Haskell.
+
+**Key features:**
+- Multiple broker backends (PostgreSQL/PGMQ, Redis, STM)
+- Configurable timeout and retry strategies
+- Exception-safe job processing
+- Support for delayed/periodic tasks
+
+This package contains the core broker and worker implementation of the
+[haskell-bee](https://github.com/garganscript/haskell-bee) project
+(simple rewrite of Celery in Haskell).
+
+## Documentation
+
+For complete documentation, examples, and setup instructions, see the [main project README](https://github.com/garganscript/haskell-bee/blob/master/README.md).
+
+## Getting Started
+
+The quickest way to get started is to check out the [demo application](https://github.com/garganscript/haskell-bee/tree/master/demo) which shows practical examples of job processing.
diff --git a/haskell-bee.cabal b/haskell-bee.cabal
new file mode 100644
--- /dev/null
+++ b/haskell-bee.cabal
@@ -0,0 +1,133 @@
+cabal-version:      3.4
+-- The cabal-version field refers to the version of the .cabal specification,
+-- and can be different from the cabal-install (the tool) version and the
+-- Cabal (the library) version you are using. As such, the Cabal (the library)
+-- version used must be equal or greater than the version stated in this field.
+-- Starting from the specification version 2.2, the cabal-version field must be
+-- the first thing in the cabal file.
+
+-- Initial package description 'haskell-bee' generated by
+-- 'cabal init'. For further documentation, see:
+--   http://haskell.org/cabal/users-guide/
+--
+-- The name of the package.
+name:               haskell-bee
+
+-- The package version.
+-- See the Haskell package versioning policy (PVP) for standards
+-- guiding when and how versions should be incremented.
+-- https://pvp.haskell.org
+-- PVP summary:     +-+------- breaking API changes
+--                  | | +----- non-breaking API additions
+--                  | | | +--- code changes with no API change
+version:            0.1.0.0
+
+-- A short (one-line) description of the package.
+synopsis: A lightweight library for asynchronous job workers with multiple broker backends
+          
+-- Extra doc files to be distributed with the package, such as a CHANGELOG or a README.
+extra-doc-files:    README.md
+
+-- A longer description of the package.
+description:        
+    Please see the README on GitHub at <https://github.com/garganscript/haskell-bee/blob/master/haskell-bee/README.md>
+   
+-- URL for the project homepage or repository.
+homepage:           https://gitlab.iscpif.fr/gargantext/haskell-bee
+
+-- The license under which the package is released.
+license:            AGPL-3.0-or-later
+
+-- The file containing the license text.
+license-file:       LICENSE
+
+-- The package author(s).
+author:             Gargantext
+
+-- An email address to which users can send suggestions, bug reports, and patches.
+maintainer:         gargantext@iscpif.fr
+
+-- A copyright notice.
+-- copyright:
+category:           Concurrency
+build-type:         Simple
+
+-- Extra doc files to be distributed with the package, such as a CHANGELOG or a README.
+-- extra-doc-files:    CHANGELOG.md
+--                   , README.md
+
+-- Extra source files to be distributed with the package, such as examples, or a tutorial module.
+-- extra-source-files:
+
+common warnings
+    ghc-options: -Wall
+
+library
+    -- Import common warning flags.
+    import:           warnings
+
+    -- Modules exported by the library.
+    exposed-modules:  Async.Worker
+                    , Async.Worker.Broker
+                    , Async.Worker.Broker.Types
+                    , Async.Worker.Types
+
+    -- Modules included in this library but not exported.
+    -- other-modules:
+
+    -- LANGUAGE extensions used by modules in this package.
+    -- other-extensions:
+
+    -- Other library packages from which modules are imported.
+    build-depends:    base >=4.17.2.0 && < 5
+                    , aeson >= 2.1 && < 2.3
+                    , safe-exceptions >= 0.1.7 && < 0.2
+                    , stm >= 2.5.3 && < 3
+                    , text >= 1.2 && < 2.2
+                    , unbounded-delays >= 0.1.1 && < 0.2
+
+    -- Directories containing source files.
+    hs-source-dirs:   src
+
+    -- Base language which the package is written in.
+    default-language: Haskell2010
+
+    default-extensions:
+      DuplicateRecordFields
+      GeneralizedNewtypeDeriving
+      ImportQualifiedPost
+      NamedFieldPuns
+      NumericUnderscores
+      OverloadedStrings
+      RecordWildCards
+
+test-suite test-unit
+    -- Import common warning flags.
+    import:           warnings
+    
+    type:             exitcode-stdio-1.0
+    
+    build-depends:    base >=4.17.2.0 && < 5
+                    , aeson >= 2.1 && < 2.3
+                    , tasty >= 1.5 && < 1.6
+                    , tasty-quickcheck >= 0.10 && < 0.12
+                    
+                    , haskell-bee
+
+    -- Directories containing source files.
+    hs-source-dirs:   tests
+    main-is: unit-tests.hs
+
+    -- Base language which the package is written in.
+    default-language: Haskell2010
+
+    default-extensions:
+      DuplicateRecordFields
+      GeneralizedNewtypeDeriving
+      ImportQualifiedPost
+      NamedFieldPuns
+      OverloadedStrings
+      RecordWildCards
+
+    ghc-options: -threaded
+
diff --git a/src/Async/Worker.hs b/src/Async/Worker.hs
new file mode 100644
--- /dev/null
+++ b/src/Async/Worker.hs
@@ -0,0 +1,329 @@
+{-|
+Module      : Async.Worker
+Description : Abstract async worker implementation using the 'Queue' typeclass
+Copyright   : (c) Gargantext, 2024-Present
+License     : AGPL
+Maintainer  : gargantext@iscpif.fr
+Stability   : experimental
+Portability : POSIX
+
+Asynchronous worker.
+
+-}
+
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+
+module Async.Worker
+  ( KillWorkerSafely(..)
+  -- * Running
+  , run
+  , runSingle
+  , runSingle'
+    -- * Sending jobs
+  , sendJob
+  -- ** 'SendJob' wrappers
+  -- $sendJob
+  , mkDefaultSendJob
+  , mkDefaultSendJob'
+  , sendJob'
+  , SendJob(..) )
+where
+
+
+{- | 'Broker' class type for the underlying broker
+-}
+import Async.Worker.Broker
+{- | Various worker types, in particular 'State'
+-}
+import Async.Worker.Types
+import Control.Concurrent.STM (atomically)
+import Control.Concurrent.STM.TVar (readTVarIO, newTVarIO, writeTVar)
+import Control.Concurrent.Timeout qualified as Timeout
+import Control.Exception.Safe (catches, Handler(..), throwIO, SomeException, Exception)
+import Control.Monad (forever, void, when)
+
+
+-- | If you want to stop a worker safely, use `throwTo'
+-- 'workerThreadId' 'KillWorkerSafely'. This way the worker will stop
+-- whatever is doing now and resend the message back to the
+-- broker. This way you won't lose your jobs. If you don't care about
+-- resuming a job, just set 'resendWhenWorkerKilled' property to
+-- 'False'.
+data KillWorkerSafely = KillWorkerSafely
+  deriving (Show)
+instance Exception KillWorkerSafely
+
+
+-- | This is the main function to start a worker. It's an infinite
+-- loop of reading the next broker message, processing it and handling
+-- any errors, issues that might arrise in the meantime.
+run :: (HasWorkerBroker b a) => State b a -> IO ()
+run state@(State { .. }) = do
+  createQueue broker queueName
+  forever $ runSingle state
+
+-- | Fetch a single job and run it (create queue first)
+runSingle :: (HasWorkerBroker b a) => State b a -> IO ()
+runSingle state@(State { .. }) = do
+  createQueue broker queueName
+  runSingle' state
+
+-- | Fetch a single job and run it. Assumes the queue already exists
+runSingle' :: (HasWorkerBroker b a) => State b a -> IO ()
+runSingle' state@(State { .. }) = do
+      -- TVar to hold currently processed job. This is used for
+      -- exception handling.
+      mBrokerMessageTVar <- newTVarIO Nothing -- :: IO (TVar (Maybe (BrokerMessage b (Job a))))
+      
+      catches (do
+                brokerMessage <- readMessageWaiting broker queueName
+                atomically $ writeTVar mBrokerMessageTVar (Just brokerMessage)
+                handleMessage state brokerMessage
+                callWorkerJobEvent onJobFinish state brokerMessage
+            ) [
+        Handler $ \(_err :: KillWorkerSafely) -> do
+          mBrokerMessage <- readTVarIO mBrokerMessageTVar
+          case mBrokerMessage of
+            Just brokerMessage -> do
+              let job = toA $ getMessage brokerMessage
+              let mdata = metadata job
+              -- Should we resend this message?
+              when (resendWhenWorkerKilled mdata) $ do
+                -- putStrLn $ formatStr state $ "resending job: " <> show job
+                
+                -- NOTE: Delete first, then create job. It's a bit
+                -- safer (same job won't be picked up twice, though we
+                -- should be safe anyways, with the timeout)
+                void $ deleteMessage broker queueName $ messageId brokerMessage
+                void $ sendJob broker queueName (job { metadata = mdata { readCount = readCount mdata + 1 } })
+                -- size <- getQueueSize broker queueName
+                -- putStrLn $ formatStr state $ "queue size: " <> show size
+                
+              -- In any case, deinit the broker (i.e. close connection)
+              -- deinitBroker broker
+            Nothing -> pure ()
+            
+          -- callback
+          callWorkerMJobEvent onWorkerKilledSafely state mBrokerMessage
+          
+          -- kill worker
+          throwIO KillWorkerSafely
+        , Handler $ \(err :: JobTimeout b a) -> handleTimeoutError state err
+        , Handler $ \err -> do
+            mBrokerMessage <- readTVarIO mBrokerMessageTVar
+            case mBrokerMessage of
+              Just brokerMessage -> do
+                callWorkerJobErrorEvent onJobError state brokerMessage err
+                handleJobError state brokerMessage
+              Nothing -> handleUnknownError state err
+        ]
+ 
+handleMessage :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()
+handleMessage state@(State { .. }) brokerMessage = do
+  callWorkerJobEvent onMessageReceived state brokerMessage
+  let msgId = messageId brokerMessage
+  let msg = getMessage brokerMessage
+  let job' = toA msg
+  -- putStrLn $ formatStr state $ "received job: " <> show (job job')
+  let mdata = metadata job'
+  let timeoutS = jobTimeout job'
+  -- Inform the broker how long a task could take. This way we prevent
+  -- the broker from sending this task to another worker (e.g. 'vt' in
+  -- PGMQ).
+  setMessageTimeout broker queueName msgId (TimeoutS timeoutS)
+  -- mTimeout <- Timeout.timeout timeoutS (wrapPerformActionInJobException state brokerMessage)
+  mTimeout <- Timeout.timeout ((fromIntegral timeoutS) * microsecond) (runAction state brokerMessage)
+
+  let archiveHandler = do
+        case archiveStrategy mdata of
+          ASDelete -> do
+            -- putStrLn $ formatStr state $ "deleting completed job " <> show msgId <> " (strategy: " <> show archiveStrategy <> ")"
+            deleteMessage broker queueName msgId
+          ASArchive -> do
+            -- putStrLn $ formatStr state $ "archiving completed job " <> show msgId <> " (strategy: " <> show archiveStrategy <> ")"
+            archiveMessage broker queueName msgId
+  
+  case mTimeout of
+    Just _ -> archiveHandler
+    Nothing -> do
+      callWorkerJobEvent onJobTimeout state brokerMessage
+      throwIO $ JobTimeout { jtBMessage = brokerMessage
+                           , jtTimeout = timeoutS }
+  -- onMessageFetched broker queue msg
+
+
+-- -- | It's important to know if an exception occured inside a job. This
+-- -- way we can apply error recovering strategy and adjust this job in
+-- -- the broker
+-- wrapPerformActionInJobException :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()
+-- wrapPerformActionInJobException state@(State { onJobError }) brokerMessage = do
+--   catch (do
+--             runAction state brokerMessage
+--         )
+--     (\(err :: SomeException) -> do
+--         callWorkerJobEvent onJobError state brokerMessage
+--         throwIO err
+--         )
+
+
+callWorkerJobEvent :: WorkerJobEvent b a
+                   -> State b a
+                   -> BrokerMessage b (Job a)
+                   -> IO ()
+callWorkerJobEvent Nothing _ _ = pure ()
+callWorkerJobEvent (Just event) state brokerMessage = event state brokerMessage
+
+callWorkerJobErrorEvent :: WorkerJobErrorEvent b a
+                        -> State b a
+                        -> BrokerMessage b (Job a)
+                        -> SomeException
+                        -> IO ()
+callWorkerJobErrorEvent Nothing _ _ _ = pure ()
+callWorkerJobErrorEvent (Just event) state brokerMessage err = event state brokerMessage err
+
+callWorkerMJobEvent :: WorkerMJobEvent b a
+                    -> State b a
+                    -> Maybe (BrokerMessage b (Job a))
+                    -> IO ()
+callWorkerMJobEvent Nothing _ _ = pure ()
+callWorkerMJobEvent (Just event) state mBrokerMessage = event state mBrokerMessage
+
+handleTimeoutError :: (HasWorkerBroker b a) => State b a -> JobTimeout b a -> IO ()
+handleTimeoutError _state@(State { .. }) _jt@(JobTimeout { .. }) = do
+  -- putStrLn $ formatStr state $ show jt
+  let msgId = messageId jtBMessage
+  let job = toA $ getMessage jtBMessage
+  -- putStrLn $ formatStr state $ "timeout for job: " <> show job
+  let mdata = metadata job
+  case timeoutStrategy mdata of
+    TSDelete -> deleteMessage broker queueName msgId
+    TSArchive -> archiveMessage broker queueName msgId
+    TSRepeat -> do
+      void $ deleteMessage broker queueName msgId
+      void $ sendJob broker queueName (job { metadata = mdata { readCount = readCount mdata + 1 } })
+    TSRepeatNElseArchive n -> do
+      let readCt = readCount mdata
+      -- OK so this can be repeated at most 'n' times, compare 'readCt' with 'n'
+      if readCt >= n then
+        archiveMessage broker queueName msgId
+      else do
+        -- NOTE In rare cases, when worker hangs, we might lose a job
+        -- here? (i.e. delete, then resend)
+        -- Also, be aware that messsage id will change with resend
+
+        -- Delete this job first, otherwise we'll be duplicating jobs.
+        deleteMessage broker queueName msgId
+
+        -- Send this job again, with increased 'readCount'
+        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })
+    TSRepeatNElseDelete n -> do
+      let readCt = readCount mdata
+      -- OK so this can be repeated at most 'n' times, compare 'readCt' with 'n'
+      if readCt >= n then
+        deleteMessage broker queueName msgId
+      else do
+        -- NOTE In rare cases, when worker hangs, we might lose a job
+        -- here? (i.e. delete, then resend)
+        -- Also, be aware that messsage id will change with resend
+
+        -- Delete this job first, otherwise we'll be duplicating jobs.
+        deleteMessage broker queueName msgId
+
+        -- Send this job again, with increased 'readCount'
+        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })
+
+handleJobError :: (HasWorkerBroker b a) => State b a -> BrokerMessage b (Job a) -> IO ()
+handleJobError _state@(State { .. }) brokerMessage = do
+  let msgId = messageId brokerMessage
+  let job = toA $ getMessage brokerMessage
+  -- putStrLn $ formatStr state $ "error: " <> show je <> " for job " <> show job
+  let mdata = metadata job
+  case errorStrategy mdata of
+    ESDelete -> deleteMessage broker queueName msgId
+    ESArchive -> archiveMessage broker queueName msgId
+    ESRepeatNElseArchive n -> do
+      let readCt = readCount mdata
+      if readCt >= n then
+        archiveMessage broker queueName msgId
+      else do
+        -- Delete this job first, otherwise we'll be duplicating jobs.
+        deleteMessage broker queueName msgId
+
+        void $ sendJob broker queueName (job { metadata = mdata { readCount = readCt + 1 } })
+
+handleUnknownError :: State b a -> SomeException -> IO ()
+handleUnknownError state err = putStrLn $ formatStr state $ "unknown error: " <> show err
+
+sendJob :: (HasWorkerBroker b a) => Broker b (Job a) -> Queue -> Job a -> IO (MessageId b)
+sendJob broker queueName job =
+  sendJobDelayed broker queueName job 0
+
+sendJobDelayed :: (HasWorkerBroker b a) => Broker b (Job a) -> Queue -> Job a -> TimeoutS -> IO (MessageId b)
+sendJobDelayed broker queueName job timeoutS = do
+  sendMessageDelayed broker queueName (toMessage job) timeoutS
+
+microsecond :: Integer
+microsecond = 10^(6 :: Integer)
+
+
+{- $sendJob
+ A worker job has quite a few metadata. Here are some utilities for
+ constructing them more easily.
+-}
+
+-- | Wraps parameters for the 'sendJob' function
+data SendJob b a =
+  SendJob { broker       :: Broker b (Job a)
+          , queue        :: Queue
+          , msg          :: a
+          , delay        :: TimeoutS  -- initial delay for the message
+          , archStrat    :: ArchiveStrategy
+          , errStrat     :: ErrorStrategy
+          , toStrat      :: TimeoutStrategy
+          , timeout      :: Timeout
+          , resendOnKill :: Bool}
+
+-- | Create a 'SendJob' data with some defaults
+mkDefaultSendJob :: Broker b (Job a)
+                 -> Queue
+                 -> a
+                 -> Timeout
+                 -> SendJob b a
+mkDefaultSendJob broker queue msg timeout =
+  SendJob { broker
+          , queue
+          , msg
+          , delay = 0
+          -- | remove finished jobs
+          , archStrat = ASDelete
+          -- | archive errored jobs (for inspection later)
+          , errStrat = ESArchive
+          -- | repeat timed out jobs
+          , toStrat = TSRepeat
+          , timeout
+          , resendOnKill = True }
+
+
+-- | Like 'mkDefaultSendJob' but with default timeout
+mkDefaultSendJob' :: Broker b (Job a)
+                  -> Queue
+                  -> a
+                  -> SendJob b a
+mkDefaultSendJob' b q m = mkDefaultSendJob b q m defaultTimeout
+  where
+    defaultTimeout = 10
+
+    
+-- | Call 'sendJob' with 'SendJob b a' data
+sendJob' :: (HasWorkerBroker b a) => SendJob b a -> IO (MessageId b)
+sendJob' (SendJob { .. }) = do
+  let metadata = defaultMetadata { archiveStrategy = archStrat
+                                 , errorStrategy = errStrat
+                                 , timeoutStrategy = toStrat
+                                 , timeout = timeout
+                                 , resendWhenWorkerKilled = resendOnKill }
+  let job = Job { job = msg, metadata }
+  sendJobDelayed broker queue job delay
diff --git a/src/Async/Worker/Broker.hs b/src/Async/Worker/Broker.hs
new file mode 100644
--- /dev/null
+++ b/src/Async/Worker/Broker.hs
@@ -0,0 +1,15 @@
+{-|
+Module      : Async.Worker.Broker
+Description : Typeclass for the underlying broker that powers the worker
+Copyright   : (c) Gargantext, 2024-Present
+License     : AGPL
+Maintainer  : gargantext@iscpif.fr
+Stability   : experimental
+Portability : POSIX
+-}
+
+module Async.Worker.Broker
+  ( module Async.Worker.Broker.Types )
+where
+
+import Async.Worker.Broker.Types
diff --git a/src/Async/Worker/Broker/Types.hs b/src/Async/Worker/Broker/Types.hs
new file mode 100644
--- /dev/null
+++ b/src/Async/Worker/Broker/Types.hs
@@ -0,0 +1,177 @@
+{-|
+Module      : Async.Worker.Broker.Types
+Description : Typeclass for the underlying broker that powers the worker
+Copyright   : (c) Gargantext, 2024-Present
+License     : AGPL
+Maintainer  : gargantext@iscpif.fr
+Stability   : experimental
+Portability : POSIX
+
+Broker typeclass definition.
+-}
+
+
+{-# LANGUAGE ConstraintKinds       #-}
+{-# LANGUAGE DerivingStrategies    #-}
+{-# LANGUAGE FlexibleContexts      #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE ScopedTypeVariables   #-}
+{-# LANGUAGE TypeFamilies          #-}
+{-# LANGUAGE UndecidableInstances  #-}
+    
+module Async.Worker.Broker.Types
+  ( Queue(..)
+  , renderQueue
+  , TimeoutS(..)
+  -- * Main broker typeclass
+  -- $broker
+  , MessageBroker(..)
+  , SerializableMessage
+  )
+where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Kind (Type)
+import Data.String (IsString)
+import Data.Text qualified as T
+import Data.Typeable (Typeable)
+
+
+newtype Queue = Queue { _Queue :: T.Text }
+  deriving stock (Eq, Ord)
+  deriving newtype (Semigroup, IsString, Show)
+
+-- | This is just a wrapper so that you know you use seconds as units
+-- for `Int`.
+newtype TimeoutS = TimeoutS { _TimeoutS :: Int  } -- timeout for a message, in seconds
+  deriving stock (Eq, Ord)
+  deriving newtype (Num, Show)
+
+renderQueue :: Queue -> String
+renderQueue = T.unpack . _Queue
+
+{- $broker
+/NOTE/ There are 3 types of messages here:
+
+ * 'a' the underlying, user-defined message
+ * 'Async.Worker.Types.Job' 'a' worker definition, containing message metadata
+ * 'BrokerMessage' 'message' 'm', i.e. for 'PGMQ', it returns things
+   like: 'Database.Broker.PGMQ.Simple.msgId',
+   'Database.Broker.PGMQ.Simple.readCt',
+   'Database.Broker.PGMQ.Simple.enqueuedAt',
+   'Database.Broker.PGMQ.Simple.vt'
+
+Also:
+
+ * 'a' is read-write
+ * 'Async.Worker.Types.Job' 'a' is read-write
+ * 'BrokerMessage' is read-only, i.e. we can't save it to broker and
+   it doesn't make sense to construct it on Haskell side. Instead, we
+   save 'Job' 'a' and get 'BrokerMessage' when reading. In this sense,
+   read and send are not symmetrical (similarly, Opaleye has Read and
+   Write tables).
+-}
+
+-- | We want to assert some way to serialize a message. JSON is
+-- assumed here. This isn't strictly broker-related but nevertheless
+-- is useful.
+type SerializableMessage a = ( FromJSON a
+                             , ToJSON a
+                             -- NOTE This shouldn't be necessary
+                             , Typeable a )
+           
+{-|
+  This is an interface for basic broker functionality.
+-}
+class (
+        Eq (MessageId b)
+      , Show (MessageId b)
+      , Ord (MessageId b)
+      , ToJSON (MessageId b)
+      , FromJSON (MessageId b)
+      , Show (BrokerMessage b a)
+      ) => MessageBroker b a where
+  -- | Data representing the broker
+  data family Broker b a :: Type
+  -- | Data represenging message that is returned by broker. You're
+  -- not supposed to construct this type yourself (in similar spirit,
+  -- Opaleye uses 'selectTable'
+  -- https://hackage.haskell.org/package/opaleye-0.10.3.1/docs/Opaleye-Table.html#v:selectTable)
+  data family BrokerMessage b a :: Type
+  -- | Data that we serialize into broker (worker will wrap this into
+  -- 'Async.Worker.Types.Job' 'a')
+  data family Message b a :: Type
+  -- | The message id type (needed for delete/archive operations)
+  data family MessageId b :: Type
+
+  -- | All the parameters needed for broker intialization
+  data family BrokerInitParams b a :: Type
+
+  -- The following are just constructors and deconstructors for the
+  -- 'BrokerMessage', 'Message' data types
+  
+  -- | Operation for getting the 'MessageId' from 'BrokerMessage'
+  messageId :: BrokerMessage b a -> MessageId b
+  
+  -- | 'BrokerMessage' contains 'Message' inside, this is a
+  -- deconstructor for 'BrokerMessage'
+  getMessage :: BrokerMessage b a -> Message b a
+
+  -- | Convert 'a' to 'Message' 'b' 'a'
+  toMessage :: a -> Message b a
+  -- | Convert 'Message' 'b' 'a' to 'a'
+  toA :: Message b a -> a
+
+  
+  -- | Initialize broker with given 'BrokerInitParams'.
+  initBroker :: BrokerInitParams b a -> IO (Broker b a)
+  -- | Deconstruct broker (e.g. close DB connection)
+  deinitBroker :: Broker b a -> IO ()
+
+  
+  {-| Create new queue with given name. Optionally any other
+    initializations can be added here. -}
+  createQueue :: Broker b a -> Queue -> IO ()
+
+  {-| Drop queue -}
+  dropQueue :: Broker b a -> Queue -> IO ()
+
+  {-| Read message from queue, waiting for it if not present (NOTE: for
+  pgmq, this leaves the message in queue, you need to use
+  'setMessageTimeout' to prevent other workers from seeing this
+  message). -}
+  readMessageWaiting :: Broker b a -> Queue -> IO (BrokerMessage b a)
+
+  {-| Pop message from queue, waiting for it if not present -}
+  popMessageWaiting :: Broker b a -> Queue -> IO (BrokerMessage b a)
+
+  {-| We sometimes need a way to tell the broker that a message shouldn't
+  be visible for given amount of time (e.g. 'visibility timeout'
+  setting in PGMQ). The broker operates only on 'a' level and isn't
+  aware of 'Job' with its 'JobMetadata'. Hence, it's the worker's
+  responsibility to properly set timeout after message is read. -}
+  setMessageTimeout :: Broker b a -> Queue -> MessageId b -> TimeoutS -> IO ()
+
+  {-| Send message -}
+  sendMessage :: Broker b a -> Queue -> Message b a -> IO (MessageId b)
+
+  {-| Send message with initial delay -}
+  sendMessageDelayed :: Broker b a -> Queue -> Message b a -> TimeoutS -> IO (MessageId b)
+
+  {-| Delete message -}
+  deleteMessage :: Broker b a -> Queue -> MessageId b -> IO ()
+
+  {-| Archive message -}
+  archiveMessage :: Broker b a -> Queue -> MessageId b -> IO ()
+
+  {-| Queue size -}
+  getQueueSize :: Broker b a -> Queue -> IO Int
+
+  {-| Read archived message -}
+  getArchivedMessage :: Broker b a -> Queue -> MessageId b -> IO (Maybe (BrokerMessage b a))
+
+  {-| List all pending message ids -}
+  listPendingMessageIds :: Broker b a -> Queue -> IO [MessageId b]
+
+  {-| Get message by it's id -}
+  getMessageById :: Broker b a -> Queue -> MessageId b -> IO (Maybe (BrokerMessage b a))
diff --git a/src/Async/Worker/Types.hs b/src/Async/Worker/Types.hs
new file mode 100644
--- /dev/null
+++ b/src/Async/Worker/Types.hs
@@ -0,0 +1,292 @@
+{-|
+Module      : Async.Worker.Types
+Description : Types for the async worker
+Copyright   : (c) Gargantext, 2024-Present
+License     : AGPL
+Maintainer  : gargantext@iscpif.fr
+Stability   : experimental
+Portability : POSIX
+
+Types for worker.
+-}
+
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE UndecidableInstances #-}
+    
+module Async.Worker.Types
+  (
+    -- * Main worker state
+    State(..)
+  -- * Job wrapped in metadata
+  , Job(..)
+    -- ** Job metadata
+  , JobMetadata(..)
+  , defaultMetadata
+    -- *** Strategies for handling finished, errored, timed-out jobs
+  , ArchiveStrategy(..)
+  , ErrorStrategy(..)
+  , TimeoutStrategy(..)
+  -- ** Job utility functions
+  , getJob
+  , jobTimeout
+  , Timeout
+  , runAction
+  -- ** Actions that the worker will perform
+  , PerformAction
+  -- * Events emitted during job lifetime
+  , WorkerJobEvent
+  , WorkerJobErrorEvent
+  , WorkerMJobEvent
+  -- * Other useful types and functions
+  , HasWorkerBroker
+  , formatStr
+  , JobTimeout(..) )
+where
+
+import Async.Worker.Broker.Types (Broker, BrokerMessage, MessageBroker, Queue)
+import Control.Applicative ((<|>))
+import Control.Exception.Safe (Exception, SomeException)
+import Data.Aeson (FromJSON(..), ToJSON(..), object, (.=), (.:), withObject, withText)
+import Data.Text qualified as T
+import Data.Typeable (Typeable)
+
+
+type ReadCount = Int
+type Timeout = Int
+
+    
+
+-- | Strategy for archiving finished jobs
+data ArchiveStrategy =
+    -- | Delete message when it's done
+    ASDelete
+    -- | Archive message when it's done
+  | ASArchive
+  deriving (Eq, Show)
+instance ToJSON ArchiveStrategy where
+  toJSON ASDelete = toJSON ("ASDelete" :: String)
+  toJSON ASArchive = toJSON ("ASArchive" :: String)
+instance FromJSON ArchiveStrategy where
+  parseJSON = withText "ArchiveStrategy" $ \s -> do
+    case s of
+      "ASDelete" -> pure ASDelete
+      "ASArchive" -> pure ASArchive
+      s' -> fail $ T.unpack s'
+  
+-- | Strategy for handling jobs with errors
+data ErrorStrategy =
+    -- | Delete job when it threw an error
+    ESDelete
+    -- | Archive job when it threw an error
+  | ESArchive
+    -- | Try to repeat the job when an error ocurred (at most N
+    -- times), otherwise archive the job.
+  | ESRepeatNElseArchive Int
+  -- TODO Repeat N times
+  deriving (Eq, Show)
+instance ToJSON ErrorStrategy where
+  toJSON ESDelete = toJSON ("ESDelete" :: String)
+  toJSON ESArchive = toJSON ("ESArchive" :: String)
+  toJSON (ESRepeatNElseArchive n) = toJSON $ object [ "ESRepeatNElseArchive" .= n ]
+instance FromJSON ErrorStrategy where
+  parseJSON v = parseText v <|> parseESRepeatN v
+    where
+      parseText = withText "ErrorStrategy" $ \s -> do
+        case s of
+          "ESDelete" -> pure ESDelete
+          "ESArchive" -> pure ESArchive
+          s' -> fail $ T.unpack s'
+      parseESRepeatN = withObject "ESRepeatN" $ \o -> do
+        n <- o .: "ESRepeatNElseArchive"
+        pure $ ESRepeatNElseArchive n
+
+-- | Strategy for handling job timeouts
+data TimeoutStrategy =
+    -- | Delete job when it timed out
+    TSDelete
+    -- | Archive job when it timed out
+  | TSArchive
+    -- | Repeat job when it timed out (infinitely)
+  | TSRepeat
+    -- | Repeat job when it timed out (at most N times), otherwise archive it
+  | TSRepeatNElseArchive Int
+    -- | Repeat job when it timed out (at most N times), otherwise delete it
+  | TSRepeatNElseDelete Int
+  deriving (Eq, Show)
+instance ToJSON TimeoutStrategy where
+  toJSON TSDelete = toJSON ("TSDelete" :: String)
+  toJSON TSArchive = toJSON ("TSArchive" :: String)
+  toJSON TSRepeat = toJSON ("TSRepeat" :: String)
+  toJSON (TSRepeatNElseArchive n) = toJSON $ object [ "TSRepeatNElseArchive" .= n ]
+  toJSON (TSRepeatNElseDelete n) = toJSON $ object [ "TSRepeatNElseDelete" .= n ]
+instance FromJSON TimeoutStrategy where
+  parseJSON v = parseText v
+            <|> parseTSRepeatNElseArchive v
+            <|> parseTSRepeatNElseDelete v
+    where
+      -- | Parser for textual formats
+      parseText = withText "TimeoutStrategy (text)" $ \s -> do
+        case s of
+          "TSDelete" -> pure TSDelete
+          "TSArchive" -> pure TSArchive
+          "TSRepeat" -> pure TSRepeat
+          s' -> fail $ T.unpack s'
+      -- | Parser for 'TSRepeatN' object
+      parseTSRepeatNElseArchive = withObject "TimeoutStrategy (TSRepeatNElseArchive)" $ \o -> do
+        n <- o .: "TSRepeatNElseArchive"
+        pure $ TSRepeatNElseArchive n
+      parseTSRepeatNElseDelete = withObject "TimeoutStrategy (TSRepeatNElseDelete)" $ \o -> do
+        n <- o .: "TSRepeatNElseDelete"
+        pure $ TSRepeatNElseDelete n
+
+    
+-- | Metadata associated with a job.
+data JobMetadata =
+  JobMetadata {
+                -- | What to do after job is finished successfully
+                archiveStrategy  :: ArchiveStrategy
+                -- | What to do when a job ends with error
+              , errorStrategy    :: ErrorStrategy
+                -- | What to do when a job ends with timeout
+              , timeoutStrategy  :: TimeoutStrategy
+              -- | Time after which the job is considered to time-out
+              -- (in seconds).
+              , timeout          :: Timeout
+              -- | Read count so we know how many times this message
+              -- was processed
+              , readCount        :: ReadCount
+              -- | A worker might have processed a task and be
+              -- killed. If 'resendWhenWorkerKilled' is 'True', this
+              -- job will be resent to broker and picked up
+              -- later. Otherwise it will be discarded.
+              , resendWhenWorkerKilled :: Bool }
+  deriving (Eq, Show)
+instance ToJSON JobMetadata where
+  toJSON (JobMetadata { .. }) =
+    toJSON $ object [
+          "astrat" .= archiveStrategy
+        , "estrat" .= errorStrategy
+        , "tstrat" .= timeoutStrategy
+        , "timeout" .= timeout
+        , "readCount" .= readCount
+        , "resendWhenWorkerKilled" .= resendWhenWorkerKilled
+        ]
+instance FromJSON JobMetadata where
+  parseJSON = withObject "JobMetadata" $ \o -> do
+    archiveStrategy <- o .: "astrat"
+    errorStrategy <- o .: "estrat"
+    timeoutStrategy <- o .: "tstrat"
+    timeout <- o .: "timeout"
+    readCount <- o .: "readCount"
+    resendWhenWorkerKilled <- o .: "resendWhenWorkerKilled"
+    return $ JobMetadata { .. }
+
+-- | For a typical 'Job' it's probably sane to just archive it no
+-- matter how it finished.
+defaultMetadata :: JobMetadata
+defaultMetadata =
+  JobMetadata { archiveStrategy = ASArchive
+              , errorStrategy = ESArchive
+              , timeoutStrategy = TSArchive
+              , timeout = 10
+              , readCount = 0
+              , resendWhenWorkerKilled = True }
+    
+-- | Worker 'Job' is 'a' (defining action to call via 'performAction')
+-- together with associated 'JobMetadata'.
+data Job a =
+  Job { job :: a
+      , metadata :: JobMetadata }
+  deriving (Eq, Show)
+
+-- | Given worker 'Job' 'a', return the 'a' part
+getJob :: Job a -> a
+getJob (Job { job }) = job
+instance ToJSON a => ToJSON (Job a) where
+  toJSON (Job { .. }) =
+    toJSON $ object [
+          "metadata" .= metadata
+        , "job" .= job
+        ]
+instance FromJSON a => FromJSON (Job a) where
+  parseJSON = withObject "Job" $ \o -> do
+    metadata <- o .: "metadata"
+    job <- o .: "job"
+    return $ Job { .. }
+
+-- | For a given 'Job', return it's 'timeout' value from
+-- 'JobMetadata'.
+jobTimeout :: Job a -> Timeout
+jobTimeout (Job { metadata }) = timeout metadata
+    
+
+-- | Main state for a running worker ('b' is 'Broker', 'a' is the
+-- underlying message).
+--
+-- 'a' is the underlying message specification and is
+-- implementation-dependent, e.g. can be of JSON form
+--
+-- @
+-- {"function": ..., "arguments": [...]}
+-- @
+--
+-- 'Job' 'a' is worker's wrapper around that message with metadata
+-- (corresponds to broker 'Async.Worker.Broker.Types.Message' 'b'
+-- 'a'). 'BrokerMessage' 'b 'a', on the other hand, is what we get
+-- when the broker reads that message).
+--
+-- Note that our underlying 'Broker' handles messages of type 'Job'
+-- 'a'.
+data State b a =
+  State { broker            :: Broker b (Job a)
+        -- | Queue associated with this worker. If you want to support
+        -- more queues, spawn more workers.
+        , queueName         :: Queue
+        -- | Name of this worker (useful for debugging).
+        , name              :: String
+        -- | Actions that will be performed when message 'a' arrives.
+        , performAction     :: PerformAction b a
+        
+        -- | Event emitted after job was received from broker
+        , onMessageReceived :: WorkerJobEvent b a
+        -- | Event emitted after job was finished successfully
+        , onJobFinish       :: WorkerJobEvent b a
+        -- | Event emitted after job timed out
+        , onJobTimeout      :: WorkerJobEvent b a
+        -- | Event emitted after job ended with error
+        , onJobError        :: WorkerJobErrorEvent b a
+        -- | Event emitted when worker is safely killed (don't overuse it)
+        , onWorkerKilledSafely :: WorkerMJobEvent b a }
+
+-- | Helper function to call an action for given worker, for a
+-- 'BrokerMessage'.
+runAction :: State b a -> BrokerMessage b (Job a) -> IO ()
+runAction state brokerMessage = (performAction state) state brokerMessage
+
+type WorkerJobEvent b a = Maybe (State b a -> BrokerMessage b (Job a) -> IO ())
+type WorkerJobErrorEvent b a = Maybe (State b a -> BrokerMessage b (Job a) -> SomeException -> IO ())
+type WorkerMJobEvent b a = Maybe (State b a -> Maybe (BrokerMessage b (Job a)) -> IO ())
+
+-- | Callback definition (what to execute when a message arrives)
+type PerformAction b a =
+  State b a -> BrokerMessage b (Job a) -> IO ()
+
+
+-- | /TODO/ 'Show' 'a' could be removed. Any logging can be done as
+-- part of 'on' events in 'State'.
+type HasWorkerBroker b a = ( MessageBroker b (Job a), Typeable a, Typeable b, Show a )
+
+-- | Helper function to format a string with worker name (for logging)
+formatStr :: State b a -> String -> String
+formatStr (State { name }) msg =
+  "[" <> name <> "] " <> msg
+
+-- | An exception, thrown when job times out
+data JobTimeout b a =
+  JobTimeout { jtBMessage  :: BrokerMessage b (Job a)
+             , jtTimeout   :: Timeout }
+deriving instance (Show (BrokerMessage b (Job a))) => Show (JobTimeout b a)
+instance (Show (BrokerMessage b (Job a)), Typeable a, Typeable b) => Exception (JobTimeout b a)
diff --git a/tests/unit-tests.hs b/tests/unit-tests.hs
new file mode 100644
--- /dev/null
+++ b/tests/unit-tests.hs
@@ -0,0 +1,72 @@
+{-# OPTIONS_GHC -Wno-orphans -Wno-missing-signatures #-}
+
+module Main where
+
+import Async.Worker.Types qualified as WT
+import Data.Aeson qualified as Aeson
+import Test.Tasty
+import Test.Tasty.QuickCheck as QC
+    
+
+main = defaultMain tests
+
+tests :: TestTree
+tests = testGroup "Tests" [propertyTests, unitTests]
+
+
+
+propertyTests = testGroup "Property tests" [aesonPropTests]
+    
+aesonPropTests = testGroup "Aeson (de-)serialization property tests" $
+ [ aesonPropJobMetadataTests
+ , aesonPropJobTests ]
+
+instance QC.Arbitrary WT.ArchiveStrategy where
+  arbitrary = QC.elements [ WT.ASDelete, WT.ASArchive ]
+instance QC.Arbitrary WT.ErrorStrategy where 
+  arbitrary = do
+    n <- arbitrary
+    QC.elements [ WT.ESDelete, WT.ESArchive, WT.ESRepeatNElseArchive n ]
+instance QC.Arbitrary WT.TimeoutStrategy where 
+  arbitrary = do
+    n <- arbitrary
+    m <- arbitrary
+    QC.elements [ WT.TSDelete
+                , WT.TSArchive
+                , WT.TSRepeat
+                , WT.TSRepeatNElseArchive n
+                , WT.TSRepeatNElseDelete m ]
+instance QC.Arbitrary WT.JobMetadata where
+  arbitrary = do
+    archiveStrategy <- arbitrary
+    errorStrategy <- arbitrary
+    timeoutStrategy <- arbitrary
+    timeout <- arbitrary
+    readCount <- arbitrary
+    resendWhenWorkerKilled <- arbitrary
+    return $ WT.JobMetadata { .. }
+   
+aesonPropJobMetadataTests = testGroup "Aeson WT.JobMetadata (de-)serialization tests" $
+  [ QC.testProperty "Aeson.decode . Aeson.encode == id" $
+      \jm ->
+        Aeson.decode (Aeson.encode (jm :: WT.JobMetadata)) == Just jm
+  ]
+
+instance QC.Arbitrary a => QC.Arbitrary (WT.Job a) where
+  arbitrary = WT.Job <$> arbitrary <*> arbitrary
+  
+aesonPropJobTests = testGroup "Aeson WT.Job (de-)serialization tests" $
+  [ QC.testProperty "Aeson.decode . Aeson.encode == id" $
+      \j ->
+        Aeson.decode (Aeson.encode (j :: WT.Job String)) == Just j
+  ]
+
+    
+unitTests = testGroup "Unit tests" []
+  -- [ testCase "List comparison (different length)" $
+  --     [1, 2, 3] `compare` [1,2] @?= GT
+
+  -- -- the following test does not hold
+  -- , testCase "List comparison (same length)" $
+  --     [1, 2, 3] `compare` [1,2,2] @?= LT
+  -- ]