diff --git a/crates/kitsune-core/src/mapping/mastodon/sealed.rs b/crates/kitsune-core/src/mapping/mastodon/sealed.rs
index e5c6a59ec..51d3cbaca 100644
--- a/crates/kitsune-core/src/mapping/mastodon/sealed.rs
+++ b/crates/kitsune-core/src/mapping/mastodon/sealed.rs
@@ -43,7 +43,7 @@ use scoped_futures::ScopedFutureExt;
 use serde::{de::DeserializeOwned, Serialize};
 use smol_str::SmolStr;
 use speedy_uuid::Uuid;
-use std::str::FromStr;
+use std::{fmt::Write, str::FromStr};
 
 #[derive(Clone, Copy)]
 pub struct MapperState<'a> {
@@ -103,8 +103,7 @@ impl IntoMastodon for DbAccount {
 
         let mut acct = self.username.clone();
         if !self.local {
-            acct.push('@');
-            acct.push_str(&self.domain);
+            let _ = write!(acct, "@{}", self.domain);
         }
 
         let avatar = if let Some(avatar_id) = self.avatar_id {
diff --git a/crates/kitsune-http-signatures/src/header.rs b/crates/kitsune-http-signatures/src/header.rs
index cfcdfa489..2e7db914d 100644
--- a/crates/kitsune-http-signatures/src/header.rs
+++ b/crates/kitsune-http-signatures/src/header.rs
@@ -3,6 +3,7 @@ use derive_builder::Builder;
 use http::{header::DATE, request::Parts};
 use std::{
     cmp::min,
+    fmt::Write,
     time::{Duration, SystemTime, SystemTimeError},
 };
 use time::{format_description::well_known::Rfc2822, OffsetDateTime};
@@ -130,19 +131,23 @@ impl TryFrom<SignatureHeader<'_>> for String {
         );
 
         if let Some(algorithm) = value.algorithm {
-            signature_header.push_str(",algorithm=\"");
-            signature_header.push_str(algorithm);
-            signature_header.push('"');
+            let _ = write!(signature_header, ",algorithm=\"{algorithm}\"");
         }
 
         if let Some(created) = value.created {
-            signature_header.push_str(",created=");
-            signature_header.push_str(&created.to_unix_timestamp()?.to_string());
+            let _ = write!(
+                signature_header,
+                ",created={}",
+                created.to_unix_timestamp()?
+            );
         }
 
         if let Some(expires) = value.expires {
-            signature_header.push_str(",expires=");
-            signature_header.push_str(&expires.to_unix_timestamp()?.to_string());
+            let _ = write!(
+                signature_header,
+                ",expires={}",
+                expires.to_unix_timestamp()?
+            );
         }
 
         Ok(signature_header)