diff --git a/src/Database/Postgres/Temp/Internal.hs b/src/Database/Postgres/Temp/Internal.hs
--- a/src/Database/Postgres/Temp/Internal.hs
+++ b/src/Database/Postgres/Temp/Internal.hs
@@ -17,6 +17,8 @@
 import qualified Data.ByteString.Char8 as BSC
 import Control.Monad (void)
 import Network.Socket.Free (openFreePort)
+import Data.Foldable
+import Control.Concurrent.Async(race_)
 
 getFreePort :: IO Int
 getFreePort = do
@@ -82,6 +84,7 @@
 data StartError
   = InitDBFailed   ExitCode
   | CreateDBFailed [String] ExitCode
+  | StartPostgresFailed [String] ExitCode
   deriving (Show, Eq, Typeable)
 
 instance Exception StartError
@@ -167,17 +170,20 @@
       connectionString = makeConnectionString "test"
   logger StartPostgres
   let extraOptions = map (\(key, value) -> "--" ++ key ++ "=" ++ value) options
+      postgresOptions = ["-D", dataDir, "-p", show port] ++ extraOptions
   bracketOnError ( fmap (DB mainDir connectionString . fourth)
                  $ createProcess_ "postgres"
-                     ( procWith stdOut stdErr
-                      "postgres"
-                      $ ["-D", dataDir, "-p", show port] ++ extraOptions
-                     )
+                     (procWith stdOut stdErr "postgres" postgresOptions)
                  )
                  stop
                  $ \result -> do
+
+    let checkForCrash =
+          getProcessExitCode (pid result) >>=
+            traverse_ (throwIO . StartPostgresFailed postgresOptions)
+
     logger WaitForDB
-    waitForDB $ makeConnectionString "template1"
+    waitForDB (makeConnectionString "template1") `race_` checkForCrash
 
     logger CreateDB
     let createDBHostArgs = case socketType of
@@ -210,18 +216,18 @@
   e <- try $ bracket (PG.connectPostgreSQL $ BSC.pack connectionString)
           PG.close
           $ \conn -> do
-            void $ PG.execute_ conn "select pg_terminate_backend(pid) from pg_stat_activity where datname='test';" 
+            void $ PG.execute_ conn "select pg_terminate_backend(pid) from pg_stat_activity where datname='test';"
   case e of
     Left (_ :: IOError) -> pure () -- expected
-    Right _ -> pure () -- Surprising ... but I do not know yet if this is a failure of termination or not. 
+    Right _ -> pure () -- Surprising ... but I do not know yet if this is a failure of termination or not.
 
 -- | Stop postgres and clean up the temporary database folder.
 stop :: DB -> IO ExitCode
 stop db@DB {..} = do
 
   withProcessHandle pid (\case
-         OpenHandle p   -> do 
-          -- try to terminate the connects first. If we can't terminate still 
+         OpenHandle p   -> do
+          -- try to terminate the connects first. If we can't terminate still
           -- keep shutting down
           terminateConnections db
 
diff --git a/test/Database/Postgres/Temp/InternalSpec.hs b/test/Database/Postgres/Temp/InternalSpec.hs
--- a/test/Database/Postgres/Temp/InternalSpec.hs
+++ b/test/Database/Postgres/Temp/InternalSpec.hs
@@ -12,9 +12,9 @@
 import Database.PostgreSQL.Simple
 import qualified Data.ByteString.Char8 as BSC
 import System.Exit
+import System.Timeout(timeout)
 import Data.Either
 
-
 main :: IO ()
 main = hspec spec
 
@@ -69,6 +69,26 @@
         conn <- connectPostgreSQL $ BSC.pack $ connectionString db
         [Only actualDuration] <- query_ conn "SHOW log_min_duration_statement"
         actualDuration `shouldBe` expectedDuration
+
+    it "dies promptly when a bad setting is passed" $ \mainFilePath -> do
+      stdOut <- mkDevNull
+      stdErr <- mkDevNull
+      r <- timeout 5000000 $ startWithLogger print Unix 
+            [ ("log_directory", "/this/does/not/exist")
+            , ("logging_collector", "true")
+            ] mainFilePath stdOut stdErr
+      case r of
+        Nothing ->
+          -- bad test, shouldSatisfy is difficult because it wants Show on DB.
+          -- anyway, point of this is to fail if we timed out.
+          1 `shouldBe` (2 :: Int)
+        Just (Right x) ->
+          -- this would be very surprising but if it somehow manages to do something useful despite
+          -- bad config ... ok i guess? regardless, should clean up.
+          void $ stop x
+        Just (Left _) -> do
+          -- if it fails here that's fine & expected.
+          pure ()
 
     it "terminateConnections" $ \mainFilePath -> do
       stdOut <- mkDevNull
diff --git a/tmp-postgres.cabal b/tmp-postgres.cabal
--- a/tmp-postgres.cabal
+++ b/tmp-postgres.cabal
@@ -1,5 +1,5 @@
 name:                tmp-postgres
-version:             0.1.2.0
+version:             0.1.2.1
 synopsis: Start and stop a temporary postgres for testing
 description:
  This module provides functions creating a temporary postgres instance on a random port for testing.
@@ -17,7 +17,7 @@
  The start methods use a config based on the one used by pg_tmp (http://ephemeralpg.org/), but can be overriden
  by different values to the first argument of the start functions.
  .
- MacOS and Linux are support. Windows is not. 
+ MacOS and Linux are support. Windows is not.
  .
  Requires PostgreSQL 9.3+
  .
@@ -50,6 +50,7 @@
                , bytestring
                , postgresql-simple
                , port-utils
+               , async
   ghc-options: -Wall
   default-language:    Haskell2010