diff --git a/src/Crypto/Saltine/Instances.hs b/src/Crypto/Saltine/Instances.hs
index 8bbc259e0..380ec8985 100644
--- a/src/Crypto/Saltine/Instances.hs
+++ b/src/Crypto/Saltine/Instances.hs
@@ -1,5 +1,4 @@
--- {-# LANGUAGE BangPatterns #-}
-{-# OPTIONS_GHC -Wwarn #-}
+{-# OPTIONS_GHC -Wwarn -fno-warn-orphans #-}
 
 -- SPDX-FileCopyrightText: 2024-2025 Sarah Vaupel <sarah.vaupel@uniworx.de>
 --
@@ -64,8 +63,9 @@ foreign import ccall unsafe "sodium_bin2hex"
 bin2hex :: ByteString -> String
 bin2hex bs = let tlen = S.length bs * 2 + 1 in
     S8.unpack . S8.init . snd . buildUnsafeByteString tlen $ \t ->
-        constByteStrings [bs] $ \[(pbs, _)] ->
-                c_sodium_bin2hex t (fromIntegral tlen) pbs (fromIntegral $ S.length bs)
+      let aux [(pbs, _)] = c_sodium_bin2hex t (fromIntegral tlen) pbs (fromIntegral $ S.length bs)
+          aux _          = error "Crypto.Saltine.Instances.bin2hex reached an impossible computation path"
+      in constByteStrings [bs] aux
 
 instance Show Key where
     show k = "SecretBox.Key {hashesTo = \"" <> (bin2hex . shorthash nullShKey $ encode k) <> "}\""