diff --git a/Cargo.toml b/Cargo.toml
index 1f2a626..ddd696e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,7 @@ homepage = "https://github.com/zakarumych/allocator-api2"
 repository = "https://github.com/zakarumych/allocator-api2"
 readme = "README.md"
 description = "Mirror of Rust's allocator API"
+rust-version = "1.63.0"
 
 [features]
 alloc = []