diff --git a/age-core/src/plugin.rs b/age-core/src/plugin.rs
index 3334670a..7dc0063d 100644
--- a/age-core/src/plugin.rs
+++ b/age-core/src/plugin.rs
@@ -176,15 +176,13 @@ impl<R: Read, W: Write> Connection<R, W> {
     fn grease_gun(&mut self) -> impl Iterator<Item = Stanza> {
         // Add 5% grease
         let mut rng = thread_rng();
-        (0..2)
-            .map(move |_| {
-                if rng.gen_range(0..100) < 5 {
-                    Some(grease_the_joint())
-                } else {
-                    None
-                }
-            })
-            .flatten()
+        (0..2).filter_map(move |_| {
+            if rng.gen_range(0..100) < 5 {
+                Some(grease_the_joint())
+            } else {
+                None
+            }
+        })
     }
 
     fn done(&mut self) -> io::Result<()> {
@@ -484,7 +482,7 @@ mod tests {
             .unwrap();
         let stanza = plugin_conn
             .unidir_receive::<_, (), (), _, _, _, _>(
-                ("test", |s| Ok(s)),
+                ("test", Ok),
                 ("other", |_| Err(())),
                 (None, |_| Ok(())),
             )
diff --git a/age/src/encrypted.rs b/age/src/encrypted.rs
index 08aaa5f3..af38b828 100644
--- a/age/src/encrypted.rs
+++ b/age/src/encrypted.rs
@@ -48,7 +48,7 @@ impl<R: io::Read> IdentityState<R> {
                 let passphrase = match callbacks.request_passphrase(&fl!(
                     crate::i18n::LANGUAGE_LOADER,
                     "encrypted-passphrase-prompt",
-                    filename = filename.as_deref().unwrap_or_default()
+                    filename = filename.unwrap_or_default()
                 )) {
                     Some(passphrase) => passphrase,
                     None => todo!(),
diff --git a/age/src/identity.rs b/age/src/identity.rs
index 99fe814f..90c63b60 100644
--- a/age/src/identity.rs
+++ b/age/src/identity.rs
@@ -27,8 +27,8 @@ impl IdentityFileEntry {
             IdentityFileEntry::Native(i) => Ok(Box::new(i)),
             #[cfg(feature = "plugin")]
             IdentityFileEntry::Plugin(i) => Ok(Box::new(crate::plugin::IdentityPluginV1::new(
-                &i.plugin().to_owned(),
-                &[i],
+                i.plugin(),
+                &[i.clone()],
                 callbacks,
             )?)),
         }
@@ -43,7 +43,7 @@ impl IdentityFileEntry {
             IdentityFileEntry::Native(i) => Ok(Box::new(i.to_public())),
             #[cfg(feature = "plugin")]
             IdentityFileEntry::Plugin(i) => Ok(Box::new(crate::plugin::RecipientPluginV1::new(
-                &i.plugin().to_owned(),
+                i.plugin(),
                 &[],
                 &[i.clone()],
                 callbacks,
diff --git a/age/src/primitives/armor.rs b/age/src/primitives/armor.rs
index eaca79a2..1ac5997c 100644
--- a/age/src/primitives/armor.rs
+++ b/age/src/primitives/armor.rs
@@ -269,7 +269,7 @@ enum ArmorIs<W> {
         #[pin]
         inner: LineEndingWriter<W>,
         byte_buf: Option<Vec<u8>>,
-        encoded_buf: [u8; BASE64_CHUNK_SIZE_COLUMNS],
+        encoded_buf: Box<[u8; BASE64_CHUNK_SIZE_COLUMNS]>,
         #[cfg(feature = "async")]
         #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
         encoded_line: Option<EncodedBytes>,
@@ -293,7 +293,7 @@ impl<W: Write> ArmoredWriter<W> {
                 ArmoredWriter(ArmorIs::Enabled {
                     inner: w,
                     byte_buf: Some(Vec::with_capacity(BASE64_CHUNK_SIZE_BYTES)),
-                    encoded_buf: [0; BASE64_CHUNK_SIZE_COLUMNS],
+                    encoded_buf: Box::new([0; BASE64_CHUNK_SIZE_COLUMNS]),
                     #[cfg(feature = "async")]
                     encoded_line: None,
                 })
@@ -317,7 +317,7 @@ impl<W: Write> ArmoredWriter<W> {
             } => {
                 let byte_buf = byte_buf.unwrap();
                 let encoded =
-                    base64::encode_config_slice(&byte_buf, base64::STANDARD, &mut encoded_buf);
+                    base64::encode_config_slice(&byte_buf, base64::STANDARD, &mut encoded_buf[..]);
                 inner.write_all(&encoded_buf[..encoded])?;
                 inner.finish()
             }
@@ -359,10 +359,14 @@ impl<W: Write> Write for ArmoredWriter<W> {
                         break;
                     } else {
                         assert_eq!(
-                            base64::encode_config_slice(&byte_buf, base64::STANDARD, encoded_buf),
+                            base64::encode_config_slice(
+                                &byte_buf,
+                                base64::STANDARD,
+                                &mut encoded_buf[..],
+                            ),
                             BASE64_CHUNK_SIZE_COLUMNS
                         );
-                        inner.write_all(encoded_buf)?;
+                        inner.write_all(&encoded_buf[..])?;
                         byte_buf.clear();
                     };
                 }
@@ -390,7 +394,7 @@ impl<W: AsyncWrite> ArmoredWriter<W> {
             Format::AsciiArmor => ArmoredWriter(ArmorIs::Enabled {
                 inner: LineEndingWriter::new_async(output),
                 byte_buf: Some(Vec::with_capacity(BASE64_CHUNK_SIZE_BYTES)),
-                encoded_buf: [0; BASE64_CHUNK_SIZE_COLUMNS],
+                encoded_buf: Box::new([0; BASE64_CHUNK_SIZE_COLUMNS]),
                 encoded_line: None,
             }),
             Format::Binary => ArmoredWriter(ArmorIs::Disabled { inner: output }),
@@ -455,7 +459,11 @@ impl<W: AsyncWrite> AsyncWrite for ArmoredWriter<W> {
                     // line must be written in poll_close().
                     if !buf.is_empty() {
                         assert_eq!(
-                            base64::encode_config_slice(&byte_buf, base64::STANDARD, encoded_buf),
+                            base64::encode_config_slice(
+                                &byte_buf,
+                                base64::STANDARD,
+                                &mut encoded_buf[..],
+                            ),
                             ARMORED_COLUMNS_PER_LINE
                         );
                         *encoded_line = Some(EncodedBytes {
@@ -499,7 +507,8 @@ impl<W: AsyncWrite> AsyncWrite for ArmoredWriter<W> {
             if let Some(byte_buf) = byte_buf {
                 // Finish the armored format with a partial line (if necessary) and the end
                 // marker.
-                let encoded = base64::encode_config_slice(&byte_buf, base64::STANDARD, encoded_buf);
+                let encoded =
+                    base64::encode_config_slice(&byte_buf, base64::STANDARD, &mut encoded_buf[..]);
                 *encoded_line = Some(EncodedBytes {
                     offset: 0,
                     end: encoded,
@@ -982,7 +991,7 @@ impl<R: AsyncBufRead + Unpin> AsyncRead for ArmoredReader<R> {
                     {
                         // Emulates `AsyncBufReadExt::read_line`.
                         let mut this = self.as_mut().project();
-                        let buf: &mut String = &mut this.line_buf;
+                        let buf: &mut String = this.line_buf;
                         let mut bytes = mem::take(buf).into_bytes();
                         let mut read = 0;
                         ready!(read_line_internal(
diff --git a/age/src/scrypt.rs b/age/src/scrypt.rs
index 256e4cc6..c3dfc965 100644
--- a/age/src/scrypt.rs
+++ b/age/src/scrypt.rs
@@ -130,7 +130,7 @@ impl<'a> crate::Identity for Identity<'a> {
 
         // Place bounds on the work factor we will accept (roughly 16 seconds).
         let target = target_scrypt_work_factor();
-        if log_n > self.max_work_factor.unwrap_or_else(|| target + 4) {
+        if log_n > self.max_work_factor.unwrap_or(target + 4) {
             return Some(Err(DecryptError::ExcessiveWork {
                 required: log_n,
                 target,