diff --git a/mdbx/env.go b/mdbx/env.go
index 46e7dd8..5dde6f1 100644
--- a/mdbx/env.go
+++ b/mdbx/env.go
@@ -107,6 +107,7 @@ const (
 	OptSpillMinDenominator          = C.MDBX_opt_spill_min_denominator
 	OptSpillParent4ChildDenominator = C.MDBX_opt_spill_parent4child_denominator
 	OptMergeThreshold16dot16Percent = C.MDBX_opt_merge_threshold_16dot16_percent
+	OptPreferWafInsteadofBalance    = C.MDBX_opt_prefer_waf_insteadof_balance
 )
 
 var (