diff --git a/src/FsCQRSShop.Domain/Basket.fs b/src/FsCQRSShop.Domain/Basket.fs
index 18a65c0..572da39 100644
--- a/src/FsCQRSShop.Domain/Basket.fs
+++ b/src/FsCQRSShop.Domain/Basket.fs
@@ -15,14 +15,16 @@ module Basket =
     | Init
     | Created of BasketInfo * OrderLine list
 
-    let evolveOneBasket state = function
-        | BasketCreated(basketId, customerId, discount) -> Success (Created ({Id = basketId; Discount = discount},[]))
-        | ItemAdded(basketId, orderLine) -> match state with
-                                            | Created (info, lines) -> Success (Created(info, orderLine::lines))
+    let evolveOneBasket state event = 
+        match state, event with
+        | Init, BasketCreated(basketId, customerId, discount) -> Success (Created ({Id = basketId; Discount = discount},[]))
+        | Created (info, lines), ItemAdded(basketId, orderLine) ->Success (Created(info, orderLine::lines))
+        | _ -> stateTransitionFail state event
+
     let evolveBasket = evolve evolveOneBasket
 
     let handleBasket deps pc = 
-        let getState id = evolveBasket Init ((deps.readEvents id) |> (fun (_, e) -> e))
+        let getState id = evolveBasket Init ((deps.readEvents id) |> snd)
 
         let createBasket id customerId discountResult (version,state) = 
             match state, discountResult with
@@ -66,6 +68,7 @@ module Basket =
                     let events = if orderTotal > 100000 then [NeedsApproval(orderId)] else [OrderApproved(orderId)]
                     Success (orderGuid, -1, (OrderCreated(orderId, b.Id, lines)::events))
                 | _ -> Failure InvalidPaymentAmount
+            | _ -> Failure (InvalidState "Basket")
 
         match pc with
         | CreateBasket(BasketId id, CustomerId customerId) ->
diff --git a/src/FsCQRSShop.Domain/Customer.fs b/src/FsCQRSShop.Domain/Customer.fs
index ed4a5ac..9b4415c 100644
--- a/src/FsCQRSShop.Domain/Customer.fs
+++ b/src/FsCQRSShop.Domain/Customer.fs
@@ -29,20 +29,15 @@ module Customer =
         | Init -> invalidCustomerState
 
     let evolveOneCustomer state event =
-        match state with
-        | Init -> match event with
-                  | CustomerCreated(id, name) -> Success ( Created{Id = id; Name = name})
-                  | _ -> stateTransitionFail event state
-        | Created info -> match event with
-                          | CustomerMarkedAsPreferred(id, discount) -> Success (Preferred(info,discount))
-                          | _ -> stateTransitionFail event state
-        | Preferred (info, _) -> match event with
-                                 | CustomerMarkedAsPreferred(id, discount) -> Success (Preferred(info,discount))
-                                 | _ -> stateTransitionFail event state
+        match state, event with
+        | Init, CustomerCreated(id, name) -> Success ( Created{Id = id; Name = name})
+        | Created info, CustomerMarkedAsPreferred(id, discount) -> Success (Preferred(info,discount))
+        | Preferred (info, _), CustomerMarkedAsPreferred(id, discount) -> Success (Preferred(info,discount))
+        | _ -> stateTransitionFail event state
 
     let evolveCustomer = evolve evolveOneCustomer
 
-    let getCustomerState deps id = evolveCustomer Init ((deps.readEvents id) |> (fun (_, e) -> e))
+    let getCustomerState deps id = evolveCustomer Init ((deps.readEvents id) |> snd)
 
     let handleCustomer deps cc =
         let createCustomer id name (version, state) =
diff --git a/src/FsCQRSShop.Domain/Order.fs b/src/FsCQRSShop.Domain/Order.fs
index 8998c8b..918d9ed 100644
--- a/src/FsCQRSShop.Domain/Order.fs
+++ b/src/FsCQRSShop.Domain/Order.fs
@@ -18,9 +18,10 @@ module Order =
         | OrderCreated (id, basketId, lines) -> Success (Created(id))
         | OrderCancelled (id) -> Success (Cancelled(id))
         | ShippingProcessStarted (id) -> Success (ShippingStarted(id))
+        | e -> stateTransitionFail state e
 
     let evolveOrder = evolve evolveOneOrder
-    let getOrder deps id = evolveOrder Init ((deps.readEvents id) |> (fun (_, e) -> e))
+    let getOrder deps id = evolveOrder Init ((deps.readEvents id) |> snd)
 
     let handleOrder deps pc = 
         let handleCommand id fn =
diff --git a/src/FsCQRSShop.Domain/Product.fs b/src/FsCQRSShop.Domain/Product.fs
index 33943e5..df1d56b 100644
--- a/src/FsCQRSShop.Domain/Product.fs
+++ b/src/FsCQRSShop.Domain/Product.fs
@@ -15,14 +15,12 @@ module Product =
     | Created of ProductInfo
 
     let evolveOneProduct state event = 
-        match state with
-        | Init -> match event with
-                  | ProductCreated(id, name, price) -> Success (Created {Id = id; Name = name; Price = price})
-                  | _ -> stateTransitionFail state event
+        match state, event with
+        | Init, ProductCreated(id, name, price) -> Success (Created {Id = id; Name = name; Price = price})
         | _ -> stateTransitionFail state event
 
     let evolveProduct = evolve evolveOneProduct
-    let getProduct deps id = evolveProduct Init ((deps.readEvents id) |> (fun (_, e) -> e))
+    let getProduct deps id = evolveProduct Init ((deps.readEvents id) |> snd)
 
     let handleProduct deps pc = 
         let createProduct id name price (version,state) =