diff --git a/Cargo.toml b/Cargo.toml
index 256bff8..04f6341 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.7.4"
 authors = ["bluss"]
 license = "MIT OR Apache-2.0"
 edition = "2018"
+rust-version = "1.51"
 
 description = "A vector with fixed capacity, backed by an array (it can be stored on the stack too). Implements fixed capacity ArrayVec and ArrayString."
 documentation = "https://docs.rs/arrayvec/"