diff --git a/Cargo.lock b/Cargo.lock
index adf04e9..a41cee0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -140,7 +140,7 @@ checksum = "e712f64ec3850b98572bffac52e2c6f282b29fe6c5fa6d42334b30be438d95c1"
 
 [[package]]
 name = "hkdf"
-version = "0.13.0-rc.3"
+version = "0.13.0-rc.4"
 dependencies = [
  "blobby",
  "hex-literal",
diff --git a/hkdf/Cargo.toml b/hkdf/Cargo.toml
index f8cb5cb..1dc2a57 100644
--- a/hkdf/Cargo.toml
+++ b/hkdf/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hkdf"
-version = "0.13.0-rc.3"
+version = "0.13.0-rc.4"
 authors = ["RustCrypto Developers"]
 license = "MIT OR Apache-2.0"
 homepage = "https://github.com/RustCrypto/KDFs/"