diff --git a/crates/ipu-codegen/src/package.rs b/crates/ipu-codegen/src/package.rs
index 4dd265b..3cfc4a2 100644
--- a/crates/ipu-codegen/src/package.rs
+++ b/crates/ipu-codegen/src/package.rs
@@ -1279,6 +1279,17 @@ pub fn capture_exchange_finalist(
         &Ipu21CostModel,
         planning.exchange_schedule_finalists.max(4),
     )?;
+    for (index, mid) in finalists.iter().enumerate() {
+        let mut text = String::new();
+        for op in &mid.operations {
+            text.push_str(&format!("{:?} {:?} {:?}\n", op.source, op.kind, crate::estimate::operation_cost(op, &mid.values)));
+            for id in op.inputs.iter().chain(&op.results) {
+                text.push_str(&format!("  {:?}\n", mid.values[id.index() as usize]));
+            }
+        }
+        std::fs::write(format!("/tmp/b2-historical-{index}.txt"), text).unwrap();
+    }
+    if std::env::var_os("DUMP_MID_ONLY").is_some() { return Err(invalid("diagnostic mid dump complete")); }
     let mid = finalists
         .get(finalist)
         .ok_or_else(|| invalid("exchange capture finalist out of range"))?;