diff --git a/backend/src/aurinko/updater.gleam b/backend/src/aurinko/updater.gleam
index 9575e90..13038c0 100644
--- a/backend/src/aurinko/updater.gleam
+++ b/backend/src/aurinko/updater.gleam
@@ -39,19 +39,31 @@ pub type Dataset {
   Dataset(production_info: ProductionInfo, modules: ModuleDataset)
 }
 
-pub type State {
-  InitialState(
-    username: String,
-    password: String,
-    error: option.Option(UpdateError),
-  )
-  LoadedState(
-    username: String,
-    password: String,
-    cookies: biscotto.CookieJar,
-    cookies_acquired: birl.Time,
-    ids: ModuleIDs,
+pub type Credentials {
+  Credentials(username: String, password: String)
+}
+
+pub type Cookies {
+  Cookies(jar: biscotto.CookieJar, acquired: birl.Time)
+}
+
+pub type InitialisedState {
+  InitialisedState(
+    cookies: Cookies,
+    modules: ModuleIDs,
     dataset: option.Option(Dataset),
+  )
+}
+
+pub type InnerState {
+  Pending
+  Initialised(InitialisedState)
+}
+
+pub type State {
+  State(
+    credentials: Credentials,
+    inner: InnerState,
     error: option.Option(UpdateError),
   )
 }
@@ -62,153 +74,93 @@ pub type UpdateError {
 }
 
 pub fn start(username: String, password: String) {
-  actor.start(InitialState(username, password, option.None), handle_message)
+  actor.start(
+    State(Credentials(username, password), Pending, option.None),
+    handle_message,
+  )
 }
 
 fn handle_message(message: Message, state: State) -> actor.Next(Message, State) {
   let next =
-    with_loaded_state(
-      state,
-      fn(username, password, cookies, cookies_acquired, ids, dataset) {
-        case message {
-          Update -> {
-            use #(cookies, cookies_acquired, new_dataset) <- result.try(update(
-              username,
-              password,
-              cookies,
-              cookies_acquired,
-              ids,
-              dataset,
-            ))
+    with_initialised_state(state, fn(credentials, inner_state) {
+      case message {
+        Update -> {
+          use new_state <- result.try(update(credentials, inner_state))
 
-            let new_state =
-              LoadedState(
-                username,
-                password,
-                cookies,
-                cookies_acquired,
-                ids,
-                option.Some(new_dataset),
-                option.None,
-              )
-
-            Ok(actor.continue(new_state))
-          }
+          Ok(actor.continue(State(..state, inner: Initialised(new_state))))
         }
-      },
-    )
+      }
+    })
 
   case next {
     Ok(next) -> next
     Error(err) -> {
-      let new_state = case state {
-        InitialState(username, password, ..) ->
-          InitialState(username, password, error: option.Some(err))
-        LoadedState(
-          username,
-          password,
-          cookies,
-          cookies_acquired,
-          ids,
-          dataset,
-          ..,
-        ) ->
-          LoadedState(
-            username,
-            password,
-            cookies,
-            cookies_acquired,
-            ids,
-            dataset,
-            option.Some(err),
-          )
-      }
+      let new_state = State(..state, error: option.Some(err))
       actor.continue(new_state)
     }
   }
 }
 
-fn with_loaded_state(
+fn with_initialised_state(
   state: State,
-  fun: fn(
-    String,
-    String,
-    biscotto.CookieJar,
-    birl.Time,
-    ModuleIDs,
-    option.Option(Dataset),
-  ) ->
+  fun: fn(Credentials, InitialisedState) ->
     Result(actor.Next(Message, State), UpdateError),
 ) {
-  case state {
-    InitialState(username, password, ..) -> {
-      use loaded_state <- result.try(
-        init(username, password) |> result.map_error(APIError),
-      )
-      fun(
-        username,
-        password,
-        loaded_state.0,
-        loaded_state.1,
-        loaded_state.2,
-        loaded_state.3,
+  case state.inner {
+    Pending -> {
+      use initialised_state <- result.try(
+        init(state.credentials.username, state.credentials.password)
+        |> result.map_error(APIError),
       )
+
+      fun(state.credentials, initialised_state)
     }
-    LoadedState(username, password, cookies, cookies_acquired, ids, dataset, ..) ->
-      fun(username, password, cookies, cookies_acquired, ids, dataset)
+    Initialised(inner) -> fun(state.credentials, inner)
   }
 }
 
 fn login(username: String, password: String) {
   use cookies <- result.try(api.login(username, password))
-  Ok(#(cookies, birl.utc_now()))
+  Ok(Cookies(cookies, birl.utc_now()))
 }
 
 fn init(username: String, password: String) {
-  use #(cookies, cookies_acquired) <- result.try(login(username, password))
-  use module_ids <- result.try(api.get_module_ids(cookies))
+  use cookies <- result.try(login(username, password))
+  use module_ids <- result.try(api.get_module_ids(cookies.jar))
 
-  Ok(#(cookies, cookies_acquired, module_ids, option.None))
+  Ok(InitialisedState(cookies, module_ids, option.None))
 }
 
-fn update(
-  username: String,
-  password: String,
-  cookies: biscotto.CookieJar,
-  cookies_acquired: birl.Time,
-  module_ids: ModuleIDs,
-  dataset: option.Option(Dataset),
-) {
+fn update(credentials: Credentials, state: InitialisedState) {
   let now = birl.utc_now()
   let max_lifetime = duration.seconds(login_cookie_expiry)
   let should_renew = case
-    duration.compare(birl.difference(now, cookies_acquired), max_lifetime)
+    duration.compare(birl.difference(now, state.cookies.acquired), max_lifetime)
   {
     order.Gt | order.Eq -> True
     _ -> False
   }
 
   let cookies_result = case should_renew {
-    False -> Ok(#(cookies, cookies_acquired))
-    True -> login(username, password)
+    False -> Ok(state.cookies)
+    True -> login(credentials.username, credentials.password)
   }
 
-  use #(cookies, cookies_acquired) <- result.try(
-    cookies_result |> result.map_error(APIError),
-  )
+  use cookies <- result.try(cookies_result |> result.map_error(APIError))
 
   use production_info <- result.try(
-    api.get_production(cookies) |> result.map_error(APIError),
+    api.get_production(cookies.jar) |> result.map_error(APIError),
   )
   use module_datas <- result.try(
-    api.get_module_power(cookies, module_ids) |> result.map_error(APIError),
+    api.get_module_power(cookies.jar, state.modules)
+    |> result.map_error(APIError),
   )
   use parsed_module_datas <- result.try(
     module_power.decode_api_data(module_datas)
     |> result.map_error(DecodeError),
   )
 
-  let new_dataset = case dataset {
+  let new_dataset = case state.dataset {
     option.Some(existing_dataset) ->
       Dataset(..existing_dataset, production_info: production_info)
     option.None ->
@@ -224,7 +176,13 @@ fn update(
       modules: add_module_datasets(new_dataset.modules, parsed_module_datas),
     )
 
-  Ok(#(cookies, cookies_acquired, new_dataset))
+  Ok(
+    InitialisedState(
+      ..state,
+      cookies: cookies,
+      dataset: option.Some(new_dataset),
+    ),
+  )
 }
 
 fn add_module_datasets(