diff --git a/crates/caldav/src/principal/mod.rs b/crates/caldav/src/principal/mod.rs
index b173c31..8e22e27 100644
--- a/crates/caldav/src/principal/mod.rs
+++ b/crates/caldav/src/principal/mod.rs
@@ -64,7 +64,6 @@ pub enum PrincipalPropName {
     CalendarUserAddressSet,
 }
 
-#[async_trait(?Send)]
 impl Resource for PrincipalFile {
     type PropName = PrincipalPropName;
     type Prop = PrincipalProp;
diff --git a/crates/dav/src/resource.rs b/crates/dav/src/resource.rs
index 81ed78c..e75fbc2 100644
--- a/crates/dav/src/resource.rs
+++ b/crates/dav/src/resource.rs
@@ -10,7 +10,6 @@ use serde::{Deserialize, Serialize};
 use std::str::FromStr;
 use strum::VariantNames;
 
-#[async_trait(?Send)]
 pub trait Resource: Clone {
     type PropName: FromStr + VariantNames + Clone;
     type Prop: Serialize + for<'de> Deserialize<'de> + fmt::Debug + InvalidProperty;