diff --git a/src/Lean/Compiler/LCNF/Passes.lean b/src/Lean/Compiler/LCNF/Passes.lean
index 794d969f8a..3b9dd01b36 100644
--- a/src/Lean/Compiler/LCNF/Passes.lean
+++ b/src/Lean/Compiler/LCNF/Passes.lean
@@ -50,7 +50,7 @@ def builtinPassManager : PassManager := {
     pullFunDecls,
     reduceJpArity,
     simp { etaPoly := true, inlinePartial := true, implementedBy := true } (occurrence := 1),
-    -- eagerLambdaLifting,
+    eagerLambdaLifting,
     specialize,
     simp (occurrence := 2),
     cse,