diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
-# hpqtypes-effectful-1.0.1.0 (2023-12-18)
+# hpqtypes-effectful-1.0.2.0 (2024-03-18)
 * Compatibility with `hpqtypes` >= 1.12.0.0.
+
+# hpqtypes-effectful-1.0.1.0 (2023-12-18)
+* ~~Compatibility with `hpqtypes` >= 1.12.0.0.~~
 
 # hpqtypes-effectful-1.0.0.1 (2023-03-28)
 * Compatibility with `hpqtypes` >= 1.11.1.0.
diff --git a/hpqtypes-effectful.cabal b/hpqtypes-effectful.cabal
--- a/hpqtypes-effectful.cabal
+++ b/hpqtypes-effectful.cabal
@@ -1,7 +1,7 @@
-cabal-version:      2.4
+cabal-version:      3.0
 build-type:         Simple
 name:               hpqtypes-effectful
-version:            1.0.1.0
+version:            1.0.2.0
 license:            BSD-3-Clause
 license-file:       LICENSE
 category:           Database
@@ -16,8 +16,7 @@
   CHANGELOG.md
   README.md
 
-tested-with: GHC ==8.8.4 || ==8.10.7 || ==9.0.2 || ==9.2.8 || ==9.4.7 || ==9.6.3
-              || ==9.8.1
+tested-with: GHC == { 8.10.7, 9.0.2, 9.2.8, 9.4.8, 9.6.4, 9.8.2 }
 
 bug-reports: https://github.com/haskell-effectful/hpqtypes-effectful/issues
 source-repository head
@@ -56,10 +55,10 @@
 library
   import:          language
 
-  build-depends:   base               >= 4.13      && < 5
+  build-depends:   base               >= 4.14      && < 5
                  , effectful-core     >= 1.2.0.0   && < 3.0.0.0
                  , exceptions
-                 , hpqtypes           >= 1.11.1.0  && < 1.13.0.0
+                 , hpqtypes           >= 1.12.0.0  && < 1.13.0.0
 
   hs-source-dirs:   src
 
diff --git a/src/Effectful/HPQTypes.hs b/src/Effectful/HPQTypes.hs
--- a/src/Effectful/HPQTypes.hs
+++ b/src/Effectful/HPQTypes.hs
@@ -31,6 +31,7 @@
   RunQuery :: IsSQL sql => sql -> DB m Int
   GetQueryResult :: FromRow row => DB m (Maybe (QueryResult row))
   ClearQueryResult :: DB m ()
+  GetBackendPid :: DB m BackendPid
   GetConnectionStats :: DB m PQ.ConnectionStats
   RunPreparedQuery :: IsSQL sql => PQ.QueryName -> sql -> DB m Int
   GetLastQuery :: DB m SomeSQL
@@ -47,6 +48,7 @@
   runQuery = withFrozenCallStack $ send . RunQuery
   getQueryResult = send GetQueryResult
   clearQueryResult = send ClearQueryResult
+  getBackendPid = send GetBackendPid
   getConnectionStats = withFrozenCallStack $ send GetConnectionStats
   runPreparedQuery qn = withFrozenCallStack $ send . RunPreparedQuery qn
   getLastQuery = send GetLastQuery
@@ -62,7 +64,7 @@
 -- /Note:/ this is the @effectful@ version of 'runDBT'.
 runDB
   :: forall es a
-   . (IOE :> es)
+   . IOE :> es
   => PQ.ConnectionSourceM (Eff es)
   -- ^ Connection source.
   -> TransactionSettings
@@ -74,6 +76,7 @@
     RunQuery sql -> unDBEff $ runQuery sql
     GetQueryResult -> unDBEff getQueryResult
     ClearQueryResult -> unDBEff clearQueryResult
+    GetBackendPid -> unDBEff getBackendPid
     GetConnectionStats -> unDBEff getConnectionStats
     RunPreparedQuery queryName sql -> unDBEff $ runPreparedQuery queryName sql
     GetLastQuery -> unDBEff getLastQuery
@@ -145,7 +148,7 @@
 type DBState es = PQ.DBState (Eff es)
 
 -- Convenience `MonadIO` instance
-instance (IOE :> es) => MonadIO (DBEff es) where
+instance IOE :> es => MonadIO (DBEff es) where
   liftIO b = DBEff $ liftIO b
 
 get :: DBEff es (DBState es)
@@ -157,11 +160,13 @@
 modify :: (DBState es -> DBState es) -> DBEff es ()
 modify = DBEff . State.modify
 
-instance (IOE :> es) => MonadDB (DBEff es) where
+instance IOE :> es => MonadDB (DBEff es) where
   runQuery sql = do
     dbState <- get
-    (rows, res) <- liftIO $ PQ.runQueryIO (PQ.dbConnection dbState) sql
-    put $ PQ.updateStateWith dbState sql res
+    (rows, newDbState) <- liftIO $ do
+      PQ.updateStateWith dbState sql
+        =<< PQ.runQueryIO (PQ.dbConnection dbState) sql
+    put newDbState
     pure rows
 
   getQueryResult =
@@ -170,6 +175,8 @@
   clearQueryResult =
     modify $ \st -> st {PQ.dbQueryResult = Nothing}
 
+  getBackendPid = liftIO . PQ.getBackendPidIO . PQ.dbConnection =<< get
+
   getConnectionStats = do
     dbState <- get
     mconn <- liftIO . readMVar . PQ.unConnection $ PQ.dbConnection dbState
@@ -179,8 +186,10 @@
 
   runPreparedQuery queryName sql = do
     dbState <- get
-    (rows, res) <- liftIO $ PQ.runPreparedQueryIO (PQ.dbConnection dbState) queryName sql
-    put $ PQ.updateStateWith dbState sql res
+    (rows, newDbState) <- liftIO $ do
+      PQ.updateStateWith dbState sql
+        =<< PQ.runPreparedQueryIO (PQ.dbConnection dbState) queryName sql
+    put newDbState
     pure rows
 
   getLastQuery = PQ.dbLastQuery <$> get
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -73,14 +73,14 @@
       runQuery_ $ mkSQL "SELECT 1"
       runQuery_ $ mkSQL "SELECT 2"
       connectionStats <- getConnectionStats
-      liftIO $ assertEqual "Incorrect connection stats" (ConnectionStats 2 2 2 0) connectionStats
+      liftIO $ assertEqual "Incorrect connection stats" (ConnectionStats 3 3 3 0) connectionStats
     do
       runQuery_ $ mkSQL "CREATE TABLE some_table (field INT)"
       runQuery_ $ mkSQL "BEGIN"
       runQuery_ $ mkSQL "INSERT INTO some_table VALUES (1)"
       withNewConnection $ do
         connectionStats <- getConnectionStats
-        liftIO $ assertEqual "Connection stats should be reset" (ConnectionStats 0 0 0 0) connectionStats
+        liftIO $ assertEqual "Connection stats should be reset" (ConnectionStats 1 1 1 0) connectionStats
         noOfResults <- runQuery $ mkSQL "SELECT * FROM some_table"
         liftIO $ assertEqual "Results should not be visible yet" 0 noOfResults
       runQuery_ $ mkSQL "COMMIT"