diff --git a/build/isnearupgrade.go b/build/isnearupgrade.go
new file mode 100644
index 000000000..4273f0e9e
--- /dev/null
+++ b/build/isnearupgrade.go
@@ -0,0 +1,9 @@
+package build
+
+import (
+	"github.com/filecoin-project/go-state-types/abi"
+)
+
+func IsNearUpgrade(epoch, upgradeEpoch abi.ChainEpoch) bool {
+	return epoch > upgradeEpoch-Finality && epoch < upgradeEpoch+Finality
+}