diff --git a/src-literatetests/15-regressions.blt b/src-literatetests/15-regressions.blt
index dda42a0..7654285 100644
--- a/src-literatetests/15-regressions.blt
+++ b/src-literatetests/15-regressions.blt
@@ -519,3 +519,9 @@ deriveFromJSON (unPrefix "assignPost") ''AssignmentPost
 func = do
   let !forced = some
   pure ()
+
+#test let-in-hanging
+spanKey p q = case minViewWithKey q of
+  Just ((k, _), q') | p k ->
+    let (kas, q'') = spanKey p q' in ((k, a) : kas, q'')
+  _ -> ([], q)
diff --git a/src/Language/Haskell/Brittany/Internal/Layouters/Decl.hs b/src/Language/Haskell/Brittany/Internal/Layouters/Decl.hs
index c6ff4e0..9681453 100644
--- a/src/Language/Haskell/Brittany/Internal/Layouters/Decl.hs
+++ b/src/Language/Haskell/Brittany/Internal/Layouters/Decl.hs
@@ -300,10 +300,13 @@ layoutPatternBindFinal alignmentToken binderDoc mPatDoc clauseDocs mWhereDocs ha
       ]
   let singleLineGuardsDoc guards = appSep $ case guards of
         []  -> docEmpty
-        [g] -> docSeq [appSep $ docLit $ Text.pack "|", return g]
+        [g] -> docSeq
+               [appSep $ docLit $ Text.pack "|", docForceSingleline $ return g]
         gs  -> docSeq
             $  [appSep $ docLit $ Text.pack "|"]
-            ++ List.intersperse docCommaSep (return <$> gs)
+            ++ (List.intersperse docCommaSep
+                                 (docForceSingleline . return <$> gs)
+               )
 
   indentPolicy <- mAsk
     <&> _conf_layout