diff --git a/Cargo.toml b/Cargo.toml
index ed38c8e..0c2d205 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,12 +17,12 @@ base64 = "0.21"
 base64-serde = "0.7"
 bytes = "1"
 proptest = { version = "1.0", optional = true }
-proptest-derive = { version = "0.3", optional = true }
+proptest-derive = { version = "0.4", optional = true }
 serde = "1"
 
 [dev-dependencies]
 proptest = "1.0"
-proptest-derive = "0.3"
+proptest-derive = "0.4"
 serde_json = "1"
 
 [features]