diff --git a/Cargo.toml b/Cargo.toml
index 2e17bae..1816538 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,6 +13,7 @@ license = "MIT"
 exclude = ["assets/*", ".github", "Makefile.toml", "CONTRIBUTING.md", "*.log", "tags"]
 autoexamples = true
 edition = "2021"
+rust-version = "1.56.1"
 
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