diff --git a/scripts/conventional.sh b/scripts/conventional.sh
index 73e4383..5faa6b3 100755
--- a/scripts/conventional.sh
+++ b/scripts/conventional.sh
@@ -35,10 +35,16 @@ determine_bump() {
   local bump="none"
 
   while IFS= read -r message; do
-    # Check for breaking changes
+    # Check for breaking changes — major wins; finish consuming stdin so the
+    # upstream pipeline doesn't get EPIPE on its remaining writes.
     if [[ "$message" =~ ^[a-zA-Z]+(\(.+\))?!: ]] || [[ "$message" =~ BREAKING[[:space:]]CHANGE ]]; then
-      echo "major"
-      return
+      bump="major"
+      continue
+    fi
+
+    # Skip further checks once we've locked in major.
+    if [[ "$bump" == "major" ]]; then
+      continue
     fi
 
     # Check for features
diff --git a/tests/conventional.bats b/tests/conventional.bats
index 045056e..d26f09c 100644
--- a/tests/conventional.bats
+++ b/tests/conventional.bats
@@ -64,6 +64,19 @@ setup() {
   [[ "$result" == "major" ]]
 }
 
+@test "determine_bump: consumes the full stream after locking in major (no SIGPIPE)" {
+  # Producer pipeline that mirrors create-release-pr.sh — many lines piped in,
+  # with the breaking change up front. If determine_bump returns early, the
+  # remaining echos hit a closed pipe and emit "Broken pipe" on stderr.
+  err=$(
+    {
+      echo "feat!: break stuff"
+      for i in $(seq 1 50); do echo "fix: thing ${i}"; done
+    } | determine_bump 2>&1 >/dev/null
+  )
+  [[ -z "$err" ]]
+}
+
 @test "determine_bump: none for non-conventional commits" {
   result=$(echo "update readme" | determine_bump)
   [[ "$result" == "none" ]]