diff --git a/src-tauri/src/transcription/mod.rs b/src-tauri/src/transcription/mod.rs
index 783775a..5462a83 100644
--- a/src-tauri/src/transcription/mod.rs
+++ b/src-tauri/src/transcription/mod.rs
@@ -533,6 +533,26 @@ pub fn run_streaming_worker<T, F>(
 mod tests {
     use super::*;
 
+    // Collect a step's emitted segments into `out` — the pushing closure lives
+    // and dies inside the call, so `out` is free to read in the asserts after
+    // (a single long-lived `on` closure would keep `out` mutably borrowed).
+    fn feed_into<D: Fn(&[f32], u64) -> String>(
+        s: &mut Streamer,
+        chunk: &[f32],
+        decode: &D,
+        out: &mut Vec<TranscriptSegment>,
+    ) {
+        s.feed(chunk, decode, &mut |seg| out.push(seg));
+    }
+
+    fn flush_into<D: Fn(&[f32], u64) -> String>(
+        s: &mut Streamer,
+        decode: &D,
+        out: &mut Vec<TranscriptSegment>,
+    ) {
+        s.flush(decode, &mut |seg| out.push(seg));
+    }
+
     #[test]
     fn streamer_grows_interim_then_commits_on_a_pause() {
         // Text grows for two steps, then repeats (the speaker paused, so the
@@ -551,12 +571,11 @@ mod tests {
             texts.get(i).copied().unwrap_or("hello world").to_string()
         };
         let mut out: Vec<TranscriptSegment> = Vec::new();
-        let mut on = |seg: TranscriptSegment| out.push(seg);
         let step = vec![0.0f32; 16_000]; // exactly one 1s step
 
-        s.feed(&step, &decode, &mut on); // "hello" — interim
-        s.feed(&step, &decode, &mut on); // "hello world" — interim
-        s.feed(&step, &decode, &mut on); // stable + past min_commit → commit
+        feed_into(&mut s, &step, &decode, &mut out); // "hello" — interim
+        feed_into(&mut s, &step, &decode, &mut out); // "hello world" — interim
+        feed_into(&mut s, &step, &decode, &mut out); // stable + past min_commit → commit
 
         assert_eq!(out.len(), 3);
         assert!(out[0].interim && out[0].text == "hello");
@@ -566,7 +585,7 @@ mod tests {
 
         // A new line after the commit uses a fresh id and a later offset.
         let d2 = |_: &[f32], _o: u64| "next sentence".to_string();
-        s.feed(&step, &d2, &mut on);
+        feed_into(&mut s, &step, &d2, &mut out);
         assert!(out[3].interim && out[3].text == "next sentence");
         assert_ne!(out[3].id, out[2].id);
         assert!(out[3].start_ms >= 3000, "starts after the 3 committed steps");
@@ -577,10 +596,9 @@ mod tests {
         let mut s = Streamer::new(StreamTuning::new(false));
         let decode = |_: &[f32], _o: u64| String::new();
         let mut out: Vec<TranscriptSegment> = Vec::new();
-        let mut on = |seg: TranscriptSegment| out.push(seg);
         let step = vec![0.0f32; 16_000];
         for _ in 0..5 {
-            s.feed(&step, &decode, &mut on);
+            feed_into(&mut s, &step, &decode, &mut out);
         }
         assert!(out.is_empty(), "silence must not emit an empty line");
     }
@@ -590,10 +608,9 @@ mod tests {
         let mut s = Streamer::new(StreamTuning::new(false));
         let decode = |_: &[f32], _o: u64| "partial".to_string();
         let mut out: Vec<TranscriptSegment> = Vec::new();
-        let mut on = |seg: TranscriptSegment| out.push(seg);
-        s.feed(&vec![0.0f32; 16_000], &decode, &mut on);
+        feed_into(&mut s, &vec![0.0f32; 16_000], &decode, &mut out);
         assert!(out.last().unwrap().interim, "still growing before flush");
-        s.flush(&decode, &mut on);
+        flush_into(&mut s, &decode, &mut out);
         let last = out.last().unwrap();
         assert!(!last.interim && last.text == "partial", "flush finalizes it");
     }
@@ -616,11 +633,10 @@ mod tests {
             format!("word{i}")
         };
         let mut out: Vec<TranscriptSegment> = Vec::new();
-        let mut on = |seg: TranscriptSegment| out.push(seg);
         let step = vec![0.0f32; 16_000];
-        s.feed(&step, &decode, &mut on); // 1s
-        s.feed(&step, &decode, &mut on); // 2s
-        s.feed(&step, &decode, &mut on); // 3s == max → force commit despite changing text
+        feed_into(&mut s, &step, &decode, &mut out); // 1s
+        feed_into(&mut s, &step, &decode, &mut out); // 2s
+        feed_into(&mut s, &step, &decode, &mut out); // 3s == max → force commit
         assert!(!out.last().unwrap().interim);
     }