diff --git a/rustsat/Cargo.toml b/rustsat/Cargo.toml
index 2d6935e1..c07f4e87 100644
--- a/rustsat/Cargo.toml
+++ b/rustsat/Cargo.toml
@@ -8,6 +8,7 @@ description = "This library aims to provide implementations of elements commonly
 keywords = ["sat", "satisfiability", "encodings"]
 repository = "https://github.com/chrjabs/rustsat"
 readme = "README.md"
+rust-version = "1.66.1"
 
 build = "build.rs"