diff --git a/_cmptest/sha256demo/sha256.go b/_cmptest/sha256demo/sha256.go
index 41e2eab7..1ef0652d 100644
--- a/_cmptest/sha256demo/sha256.go
+++ b/_cmptest/sha256demo/sha256.go
@@ -3,9 +3,12 @@ package main
 import (
 	"crypto/sha256"
 	"fmt"
+	"io"
 )
 
 func main() {
-	sum := sha256.Sum256([]byte("hello world\n"))
-	fmt.Printf("%x", sum)
+	h := sha256.New()
+	io.WriteString(h, "The fog is getting thicker!")
+	io.WriteString(h, "And Leon's getting laaarger!")
+	fmt.Printf("%x", h.Sum(nil))
 }
diff --git a/_cmptest/sha512demo/sha512.go b/_cmptest/sha512demo/sha512.go
index eeff921f..f2bf3791 100644
--- a/_cmptest/sha512demo/sha512.go
+++ b/_cmptest/sha512demo/sha512.go
@@ -3,9 +3,12 @@ package main
 import (
 	"crypto/sha512"
 	"fmt"
+	"io"
 )
 
 func main() {
-	sum := sha512.Sum512([]byte("hello world\n"))
-	fmt.Printf("%x", sum)
+	h := sha512.New()
+	io.WriteString(h, "The fog is getting thicker!")
+	io.WriteString(h, "And Leon's getting laaarger!")
+	fmt.Printf("%x", h.Sum(nil))
 }
diff --git a/internal/lib/crypto/sha256/sha256.go b/internal/lib/crypto/sha256/sha256.go
index b96dfd55..d55b3d97 100644
--- a/internal/lib/crypto/sha256/sha256.go
+++ b/internal/lib/crypto/sha256/sha256.go
@@ -1,7 +1,6 @@
 package sha256
 
 // llgo:skipall
-
 import (
 	"hash"
 	"unsafe"
@@ -67,3 +66,8 @@ func Sum256(data []byte) (ret [Size]byte) {
 	openssl.SHA256Bytes(data, &ret[0])
 	return
 }
+
+func Sum(data []byte) (ret [Size]byte) {
+	openssl.SHA256Bytes(data, &ret[0])
+	return
+}
diff --git a/internal/lib/crypto/sha512/sha512.go b/internal/lib/crypto/sha512/sha512.go
index c566a64a..53ff4700 100644
--- a/internal/lib/crypto/sha512/sha512.go
+++ b/internal/lib/crypto/sha512/sha512.go
@@ -1,7 +1,6 @@
 package sha512
 
 // llgo:skipall
-
 import (
 	"hash"
 	"unsafe"
@@ -73,6 +72,11 @@ func Sum512(data []byte) (ret [Size]byte) {
 	return
 }
 
+func Sum(data []byte) (ret [Size]byte) {
+	openssl.SHA512Bytes(data, &ret[0])
+	return
+}
+
 func New512_224() hash.Hash {
 	panic("todo: New512_224")
 }