diff --git a/reference-impl/rust/star-lite/src/encode.rs b/reference-impl/rust/star-lite/src/encode.rs
index 57b91e0..ae43d0f 100644
--- a/reference-impl/rust/star-lite/src/encode.rs
+++ b/reference-impl/rust/star-lite/src/encode.rs
@@ -21,11 +21,35 @@ where
     I: IntoIterator<Item = (K, Vec<u8>)>,
     K: AsRef<str>,
 {
-    let partial = commit.to_partial_bytes()?;
-    let mut w = Writer::new(output);
-    w.write_header(commit.data, Some(&partial))?;
+    let mut builder = ArchiveBuilder::new(output, commit)?;
     for (k, v) in entries {
-        w.write_entry(k.as_ref(), &v)?;
+        builder.add_entry(k.as_ref(), &v)?;
+    }
+    builder.finish()
+}
+
+/// Encode a STAR-lite archive into `output` like [`encode_archive`], but with a
+/// push-style interface that works better for fallible content sources and
+/// sinks
+pub struct ArchiveBuilder<W: Write> {
+    writer: Writer<W>,
+}
+
+impl<W: Write> ArchiveBuilder<W> {
+    /// start an archive write from the header + partial commit
+    pub fn new(output: W, commit: &Commit) -> Result<Self> {
+        let partial = commit.to_partial_bytes()?;
+        let mut writer = Writer::new(output);
+        writer.write_header(commit.data, Some(&partial))?;
+        Ok(Self { writer })
+    }
+
+    /// append one record, in strict key-ascending order
+    pub fn add_entry(&mut self, key: &str, record: &[u8]) -> Result<()> {
+        self.writer.write_entry(key, record)
+    }
+
+    pub fn finish(self) -> Result<()> {
+        self.writer.finish()
     }
-    w.finish()
 }