diff --git a/pool/app/pool_user/entity.ml b/pool/app/pool_user/entity.ml
index 00df0e804..978e63ba3 100644
--- a/pool/app/pool_user/entity.ml
+++ b/pool/app/pool_user/entity.ml
@@ -151,7 +151,9 @@ module EmailAddress = struct
     let open Mrmime in
     match Mailbox.of_string email with
     | Ok _ -> Ok email
-    | Error _ -> Error PoolError.(Invalid Field.EmailAddress)
+    | Error _ -> 
+        Printf.printf "invalid_email: %s" email;
+        Error PoolError.(Invalid Field.EmailAddress)
   ;;
 
   let strip_email_suffix email =
diff --git a/pool/test/experiment_filter_test.ml b/pool/test/experiment_filter_test.ml
index 7c15c7e11..2327a971e 100644
--- a/pool/test/experiment_filter_test.ml
+++ b/pool/test/experiment_filter_test.ml
@@ -3,6 +3,113 @@ let ( let* ) x f = Lwt_result.bind (Lwt_result.lift x) f
 let ( let& ) = Lwt_result.bind
 let test_db = Test_utils.Data.database_label
 
+let session () =
+  let open Session in
+  let sid = Id.create () in
+  let now = Ptime_clock.now () in
+  let session_start = Start.create now in
+  let* session_duration =
+    Duration.create (Ptime.diff now (Ptime_clock.now ()))
+  in
+  let pid = Pool_location.Id.create () in
+  let pool_address = Pool_location.Address.virtual_ in
+  let pool_status = Pool_location.Status.Active in
+  let mapping_file = [] in
+  let* pool_location =
+    Pool_location.create
+      ~id:pid
+      "a-pool-location"
+      None
+      pool_address
+      None
+      pool_status
+      mapping_file
+  in
+  let* max_participants = ParticipantAmount.create 2112 in
+  let* min_participants = ParticipantAmount.create 1984 in
+  let* overbook = ParticipantAmount.create 7 in
+  let session =
+    Session.create
+      ~id:sid
+      session_start
+      session_duration
+      pool_location
+      max_participants
+      min_participants
+      overbook
+  in
+  Lwt_result.lift (Ok session)
+;;
+
+let experiment () =
+  let open Experiment in
+  let experiment_id = Id.create () in
+  let* title = Title.create "an-experiment-title" in
+  let* public_title = PublicTitle.create "a-public-title" in
+  let direct_registration_disabled = DirectRegistrationDisabled.create false in
+  let registration_disabled = RegistrationDisabled.create false in
+  let allow_uninvited_singup = AllowUninvitedSignup.create false in
+  let external_data_required = ExternalDataRequired.create false in
+  let show_external_data_id_links = ShowExternalDataIdLinks.create false in
+  let* experiment =
+    Experiment.create
+      ~id:experiment_id
+      title
+      public_title
+      direct_registration_disabled
+      registration_disabled
+      allow_uninvited_singup
+      external_data_required
+      show_external_data_id_links
+  in
+  let experiment_created =
+    experiment |> Experiment.created |> Pool_event.experiment
+  in
+  let& () =
+    Pool_event.handle_event test_db experiment_created |> Lwt_result.ok
+  in
+  Experiment.find test_db experiment_id
+;;
+
+let contact () =
+  let open Contact in
+  let invited_contact_id = Id.create () in
+  let* email =
+    let email =
+      Format.asprintf "user+%s@domain.test" (Id.value invited_contact_id)
+    in
+    Pool_user.EmailAddress.create email
+  in
+  let* password = Pool_user.Password.create_unvalidated "a-password" in
+  let* firstname = Pool_user.Firstname.create "firstname" in
+  let* lastname = Pool_user.Lastname.create "lastname" in
+  let terms_accepted_at =
+    Pool_user.TermsAccepted.create (Ptime_clock.now ()) |> Option.some
+  in
+  let language = Pool_common.Language.En |> Option.some in
+  let contact_created =
+    Contact.created
+      { user_id = invited_contact_id
+      ; email
+      ; password
+      ; firstname
+      ; lastname
+      ; terms_accepted_at
+      ; language
+      }
+    |> Pool_event.contact
+  in
+  let& () = Pool_event.handle_event test_db contact_created |> Lwt_result.ok in
+  Contact.find test_db invited_contact_id
+;;
+
+let invitation ~experiment ~contacts =
+  let invitation = Invitation.{ experiment; mailing = None; contacts } in
+  let event = Invitation.Created invitation |> Pool_event.invitation in
+  let& () = Pool_event.handle_event test_db event |> Lwt_result.ok in
+  Lwt_result.lift (Ok invitation)
+;;
+
 (** This test verifies that given a contact that was invited to an experiment,
     and one that was not, the contact that was not invited will show after the
     invitation exclusion filter is applied.
@@ -13,148 +120,23 @@ let test_db = Test_utils.Data.database_label
     2. creating an experiment
     3. creating a contact that is invited to the experiment
     4. creating a contact that is NOT invited to the experiment
-    5. create all entities in the database
-    6. create a filter that for invitations that includes our experiment
-    7. assert on the found contacts
+    5. create a filter that for invitations that includes our experiment
+    6. assert on the found contacts
 
     Fin. *)
 let test =
   Test_utils.case
   @@ fun () ->
-  (* 1. create a session *)
-  let _session =
-    let open Session in
-    let sid = Id.create () in
-    let now = Ptime_clock.now () in
-    let session_start = Start.create now in
-    let* session_duration =
-      Duration.create (Ptime.diff now (Ptime_clock.now ()))
-    in
-    let pid = Pool_location.Id.create () in
-    let pool_address = Pool_location.Address.virtual_ in
-    let pool_status = Pool_location.Status.Active in
-    let mapping_file = [] in
-    let* pool_location =
-      Pool_location.create
-        ~id:pid
-        "a-pool-location"
-        None
-        pool_address
-        None
-        pool_status
-        mapping_file
-    in
-    let* max_participants = ParticipantAmount.create 2112 in
-    let* min_participants = ParticipantAmount.create 1984 in
-    let* overbook = ParticipantAmount.create 7 in
-    let session =
-      Session.create
-        ~id:sid
-        session_start
-        session_duration
-        pool_location
-        max_participants
-        min_participants
-        overbook
-    in
-    Lwt_result.lift (Ok session)
-  in
-  (* 2. create an experiment *)
-  let& experiment =
-    let open Experiment in
-    let experiment_id = Id.create () in
-    let* title = Title.create "an-experiment-title" in
-    let* public_title = PublicTitle.create "a-public-title" in
-    let direct_registration_disabled =
-      DirectRegistrationDisabled.create false
-    in
-    let registration_disabled = RegistrationDisabled.create false in
-    let allow_uninvited_singup = AllowUninvitedSignup.create false in
-    let external_data_required = ExternalDataRequired.create false in
-    let show_external_data_id_links = ShowExternalDataIdLinks.create false in
-    let* experiment =
-      Experiment.create
-        ~id:experiment_id
-        title
-        public_title
-        direct_registration_disabled
-        registration_disabled
-        allow_uninvited_singup
-        external_data_required
-        show_external_data_id_links
-    in
-    let experiment_created =
-      experiment |> Experiment.created |> Pool_event.experiment
-    in
-    let& () =
-      Pool_event.handle_event test_db experiment_created |> Lwt_result.ok
-    in
-    Experiment.find test_db experiment_id
-  in
-  (* 3. create a contact that is invited to the experiment *)
-  let invited_contact_id = Contact.Id.create () in
-  let& invited_contact =
-    let open Contact in
-    let* email = Pool_user.EmailAddress.create "user@domain.test" in
-    let* password = Pool_user.Password.create_unvalidated "a-password" in
-    let* firstname = Pool_user.Firstname.create "firstname" in
-    let* lastname = Pool_user.Lastname.create "lastname" in
-    let terms_accepted_at =
-      Pool_user.TermsAccepted.create (Ptime_clock.now ()) |> Option.some
-    in
-    let language = Pool_common.Language.En |> Option.some in
-    let contact_created =
-      Contact.created
-        { user_id = invited_contact_id
-        ; email
-        ; password
-        ; firstname
-        ; lastname
-        ; terms_accepted_at
-        ; language
-        }
-      |> Pool_event.contact
-    in
-    let& () =
-      Pool_event.handle_event test_db contact_created |> Lwt_result.ok
-    in
-    Contact.find test_db invited_contact_id
-  in
-  let invitation =
-    Invitation.{ experiment; mailing = None; contacts = [ invited_contact ] }
-  in
-  (* 4. create a contact that is NOT invited to the experiment *)
-  let probe_contact_id = Contact.Id.create () in
-  let& probe_contact =
-    let open Contact in
-    let* email = Pool_user.EmailAddress.create "probe@domain.test" in
-    let* password = Pool_user.Password.create_unvalidated "a-password" in
-    let* firstname = Pool_user.Firstname.create "probe-firstname" in
-    let* lastname = Pool_user.Lastname.create "probe-lastname" in
-    let terms_accepted_at =
-      Pool_user.TermsAccepted.create (Ptime_clock.now ()) |> Option.some
-    in
-    let language = Pool_common.Language.En |> Option.some in
-    let contact =
-      { user_id = probe_contact_id
-      ; email
-      ; password
-      ; firstname
-      ; lastname
-      ; terms_accepted_at
-      ; language
-      }
-    in
-    Lwt_result.lift (Ok contact)
-  in
-  let events =
-    [ Contact.created probe_contact |> Pool_event.contact
-    ; Invitation.Created invitation |> Pool_event.invitation
-    ]
-  in
-  (* 5. create all entities in the database *)
-  let& () = Pool_event.handle_events test_db events |> Lwt_result.ok in
-  (* 6. create a filter that for invitations that includes our experiment *)
+  (* 1. creating a session *)
+  (* let _session = session () in *)
+  (* 2. creating an experiment *)
+  let& experiment = experiment () in
+  (* 3. creating a contact that is invited to the experiment *)
+  let& invited_contact = contact () in
+  let& _invitation = invitation ~experiment ~contacts:[ invited_contact ] in
+  (* 4. creating a contact that is NOT invited to the experiment *)
+  let& _probe_contact = contact () in
+  (* 5. create a filter that for invitations that includes our experiment *)
   let invitation_filter =
     let open Filter in
     let key : Key.t = Key.(Hardcoded Invitation) in
@@ -176,7 +158,7 @@ let test =
       Filter.MatchesFilter
       (Some invitation_filter)
   in
-  (* 7. assert on the found contacts *)
+  (* 6. assert on the found contacts *)
   Alcotest.(
     check
       int
diff --git a/pool/test/test_utils.ml b/pool/test/test_utils.ml
index 68dce1fed..788d0273c 100644
--- a/pool/test/test_utils.ml
+++ b/pool/test/test_utils.ml
@@ -552,6 +552,7 @@ end
    value we have. It will fail a test if the underlying promise returns an
    Error. *)
 let case fn (_switch : Lwt_switch.t) () : unit Lwt.t =
-  let result = Lwt_result.get_exn @@ Lwt_result.catch fn in
-  Lwt.map (fun _ -> ()) result
+  match%lwt fn () with
+  | Ok () -> Lwt.return_unit
+  | Error err -> Pool_common.Message.error_to_exn err |> Lwt.fail
 ;;