diff --git a/src/Database/IndexedDB/IDBFactory.js b/src/Database/IndexedDB/IDBFactory.js
index 8d5db32..44c4a98 100644
--- a/src/Database/IndexedDB/IDBFactory.js
+++ b/src/Database/IndexedDB/IDBFactory.js
@@ -14,6 +14,9 @@ const noOp2 = function noOp2() {
     return noOp;
 };
 
+const noOp3 = function noOp3() {
+    return noOp2;
+};
 
 exports._deleteDatabase = function _deleteDatabase(name) {
     return function aff(success, error) {
@@ -46,7 +49,8 @@ exports._open = function _open(fromMaybe, name, mver, req) {
             };
 
             request.onupgradeneeded = function onUpgradeNeeded(e) {
-                fromMaybe(noOp2)(req.onUpgradeNeeded)(e.target.result)(e.target.transaction)();
+                const meta = { oldVersion: e.oldVersion };
+                fromMaybe(noOp3)(req.onUpgradeNeeded)(e.target.result)(e.target.transaction)(meta)();
             };
 
             request.onerror = errorHandler(error);
diff --git a/src/Database/IndexedDB/IDBFactory.purs b/src/Database/IndexedDB/IDBFactory.purs
index 21b88e8..ece728a 100644
--- a/src/Database/IndexedDB/IDBFactory.purs
+++ b/src/Database/IndexedDB/IDBFactory.purs
@@ -30,7 +30,7 @@ import Database.IndexedDB.Core
 -- Type alias for binding listeners to an initial open action.
 type Callbacks e =
   { onBlocked       :: Maybe (Eff (| e) Unit)
-  , onUpgradeNeeded :: Maybe (Database -> Transaction -> Eff (| e) Unit)
+  , onUpgradeNeeded :: Maybe (Database -> Transaction -> { oldVersion :: Int } -> Eff (| e) Unit)
   }
 
 
diff --git a/test/Main.purs b/test/Main.purs
index d00900d..19464af 100644
--- a/test/Main.purs
+++ b/test/Main.purs
@@ -87,23 +87,25 @@ main = runMocha do
         }
       tearDown name version db
 
-
     it "open + onUpgradeNeed" do
       let name    = "db-upgrade-needed"
           version = 1
-          callback var db _ = do
-            _ <- launchAff $ modifyVar (const $ IDBDatabase.name db) var
+          callback (Tuple varName varVersion) db _ { oldVersion } = do
+            _ <- launchAff $ modifyVar (const $ IDBDatabase.name db) varName
+            _ <- launchAff $ modifyVar (const $ oldVersion) varVersion
             pure unit
-      var <- makeVar' "-"
-      db  <- IDBFactory.open name Nothing
-        { onUpgradeNeeded : Just (callback var)
+      varName <- makeVar' "-"
+      varVersion <- makeVar' (-1)
+      db <- IDBFactory.open name Nothing
+        { onUpgradeNeeded : Just (callback (Tuple varName varVersion))
         , onBlocked       : Nothing
         }
-      name <- peekVar var
-      name `shouldEqual` name
+      name' <- peekVar varName
+      version' <- peekVar varVersion
+      name' `shouldEqual` name
+      version' `shouldEqual` 0
       tearDown name version db
 
-
     it "open + onBlocked" do
       let name    = "db-blocked"
           version = 14
@@ -124,8 +126,8 @@ main = runMocha do
         { onUpgradeNeeded : Nothing
         , onBlocked       : Just (callback var)
         }
-      name <- peekVar var
-      name `shouldEqual` name
+      name' <- peekVar var
+      name' `shouldEqual` name
       tearDown name version db02
 
   describe "IDBKeyRange" do
@@ -289,7 +291,7 @@ main = runMocha do
           pure unit
 
         setup storeParams = do
-          let onUpgradeNeeded var db _ = launchAff' do
+          let onUpgradeNeeded var db _ _ = launchAff' do
                 store <- IDBDatabase.createObjectStore db "store" storeParams
                 _     <- putVar var { db, store }
                 pure unit
@@ -327,7 +329,7 @@ main = runMocha do
       tearDown db
 
     it "deleteObjectStore" do
-      let onUpgradeNeeded var db _ = launchAff' do
+      let onUpgradeNeeded var db _ _ = launchAff' do
             _ <- IDBDatabase.deleteObjectStore db "store"
             putVar var true
 
@@ -350,7 +352,7 @@ main = runMocha do
           pure unit
 
         setup { storeParams, onUpgradeNeeded } = do
-          let onUpgradeNeeded' var db _ = launchAff' do
+          let onUpgradeNeeded' var db _ _ = launchAff' do
                 store <- IDBDatabase.createObjectStore db "store" storeParams
                 liftEff $ maybe (pure unit) id (onUpgradeNeeded <*> pure db <*> pure store)
                 putVar var { db, store }
@@ -506,7 +508,7 @@ main = runMocha do
                  , onUpgradeNeeded :: Maybe (Database -> Transaction -> Index -> Eff (idb :: IDB, avar :: AVAR, exception :: EXCEPTION | e') Unit)
                } -> Aff (idb :: IDB, avar :: AVAR | e) { db :: Database, index :: Index, store :: ObjectStore }
         setup { storeParams, indexParams, values, keyPath, onUpgradeNeeded } = do
-          let onUpgradeNeeded' var db tx = launchAff' do
+          let onUpgradeNeeded' var db tx _ = launchAff' do
                 store <- IDBDatabase.createObjectStore db "store" storeParams
                 _     <- traverse (uncurry (IDBObjectStore.add store)) values
                 index <- IDBObjectStore.createIndex store "index" keyPath indexParams
@@ -844,7 +846,7 @@ main = runMocha do
                  , onUpgradeNeeded :: Maybe (Database -> Transaction -> Index -> Eff (idb :: IDB, avar :: AVAR, exception :: EXCEPTION | e') Unit)
                } -> Aff (idb :: IDB, avar :: AVAR | e) { db :: Database, index :: Index, store :: ObjectStore }
         setup { storeParams, indexParams, values, keyPath, onUpgradeNeeded } = do
-          let onUpgradeNeeded' var db tx = launchAff' do
+          let onUpgradeNeeded' var db tx _ = launchAff' do
                 store <- IDBDatabase.createObjectStore db "store" storeParams
                 _     <- traverse (uncurry (IDBObjectStore.add store)) values
                 index <- IDBObjectStore.createIndex store "index" keyPath indexParams