diff --git a/Cargo.toml b/Cargo.toml
index dd16e170..b5482967 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,7 @@
 name = "proxmox-acme-rs"
 version = "0.3.2"
 authors = ["Wolfgang Bumiller <w.bumiller@proxmox.com>"]
-edition = "2018"
+edition = "2021"
 license = "AGPL-3"
 description = "ACME client library"
 exclude = [