diff --git a/src/Lean/Elab/Do.lean b/src/Lean/Elab/Do.lean
index a62cd4143b..f254f0f4d9 100644
--- a/src/Lean/Elab/Do.lean
+++ b/src/Lean/Elab/Do.lean
@@ -1451,7 +1451,8 @@ mutual
 
   partial def doSeqToCode : List Syntax → M CodeBlock
     | [] => do liftMacroM mkPureUnitAction
-    | doElem::doElems => withRef doElem do
+    | doElem::doElems => withIncRecDepth <| withRef doElem do
+      checkMaxHeartbeats "'do'-expander"
       match (← liftMacroM <| expandMacro? doElem) with
       | some doElem => doSeqToCode (doElem::doElems)
       | none =>