diff --git a/Cargo.toml b/Cargo.toml
index 27f1c49..5aba3b5 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,6 +10,7 @@ keywords = ["firestore", "auth"]
 categories = ["api-bindings","authentication"]
 maintenance = { status = "passively-maintained" }
 repository = "https://github.com/davidgraeff/firestore-db-and-auth-rs"
+rust-version = "1.64"
 
 [dependencies]
 bytes = "1.1"
diff --git a/readme.md b/readme.md
index ba538d2..5f799ca 100644
--- a/readme.md
+++ b/readme.md
@@ -9,7 +9,7 @@
 ![docs.rs](https://img.shields.io/docsrs/firestore-db-and-auth)
 
 This crate allows easy access to your Google Firestore DB via service account or OAuth impersonated Google Firebase Auth credentials.
-Minimum Rust version: 1.38
+Minimum Rust version: 1.64
 
 Features:
 * Asynchronous API