diff --git a/Cargo.toml b/Cargo.toml
index 9d5222b..1705f3c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,8 +20,8 @@ async-stream = { version = "0.3", optional = true}
 serde = { version = "1.0", features = ["derive"]}
 serde_json = "1.0"
 chrono = { version = "0.4", features = ["serde"]}
-ahash = {version = "0.7.6", features = ["serde"]}
-parking_lot = "0.12.0"
+ahash = {version = "0.8", features = ["serde"]}
+parking_lot = "0.12"
 base64 = "0.13"
 
 [features]
diff --git a/src/core/set.rs b/src/core/set.rs
index b969e34..60a0ca0 100644
--- a/src/core/set.rs
+++ b/src/core/set.rs
@@ -82,7 +82,7 @@ where
     properties: Option<Vec<U>>,
 }
 
-#[derive(Debug, Clone, Deserialize)]
+#[derive(Debug, Clone, Deserialize, Eq, PartialEq)]
 pub enum SetErrorType {
     #[serde(rename = "forbidden")]
     Forbidden,
diff --git a/src/principal/helpers.rs b/src/principal/helpers.rs
index e9c2879..fc1b683 100644
--- a/src/principal/helpers.rs
+++ b/src/principal/helpers.rs
@@ -12,7 +12,7 @@ use crate::{
     Get, Method, Set,
 };
 
-use super::{Principal, Property, Type};
+use super::{Principal, Property, Type, DKIM};
 
 impl Client {
     pub async fn individual_create(
@@ -52,6 +52,25 @@ impl Client {
             .created(&id)
     }
 
+    pub async fn domain_enable_dkim(
+        &self,
+        id: &str,
+        key: impl Into<String>,
+        selector: impl Into<String>,
+        expiration: Option<i64>,
+    ) -> crate::Result<Option<Principal>> {
+        let mut request = self.build();
+        request
+            .set_principal()
+            .update(id)
+            .secret(key)
+            .dkim(DKIM::new(Some(selector), expiration));
+        request
+            .send_single::<PrincipalSetResponse>()
+            .await?
+            .updated(id)
+    }
+
     pub async fn list_create(
         &self,
         email: impl Into<String>,
diff --git a/src/principal/mod.rs b/src/principal/mod.rs
index dcfc8e2..794beda 100644
--- a/src/principal/mod.rs
+++ b/src/principal/mod.rs
@@ -156,9 +156,9 @@ pub struct DKIM {
 }
 
 impl DKIM {
-    pub fn new(dkim_selector: Option<String>, dkim_expiration: Option<i64>) -> DKIM {
+    pub fn new(dkim_selector: Option<impl Into<String>>, dkim_expiration: Option<i64>) -> DKIM {
         DKIM {
-            dkim_selector,
+            dkim_selector: dkim_selector.map(Into::into),
             dkim_expiration,
         }
     }