diff --git a/src/encoder.rs b/src/encoder.rs
index 968a730..a41d340 100644
--- a/src/encoder.rs
+++ b/src/encoder.rs
@@ -16,20 +16,20 @@ pub trait Encoder {
             return Ok(src.into());
         }
         let len = s.chars().count();
-        let mut res = Vec::<u8>::with_capacity(len);
+        let mut res = Vec::with_capacity(len);
 
-        let res_ptr = res.as_mut_ptr();
+        // extend uses iterator size hint to skip per-element capacity checks
+        res.extend(
+            (0..len)
+                .map(|_| self.encode_grapheme(&mut src).or(fallback))
+                .flatten(),
+        );
 
-        for i in 0..len {
-            let byte = self
-                .encode_grapheme(&mut src)
-                .or(fallback)
-                .ok_or(EncodeError {})?;
-            unsafe { *res_ptr.add(i) = byte };
+        // If any encoding failed, we got fewer bytes than expected
+        if res.len() != len {
+            return Err(EncodeError {});
         }
 
-        // Safety: len is calculated for graphemes, and `res` is now fully initialized.
-        unsafe { res.set_len(len) };
         Ok(res.into())
     }
 }