diff --git a/scripts/retrieve_ci_failures.py b/scripts/retrieve_ci_failures.py
index f03fd18207..c7086af658 100644
--- a/scripts/retrieve_ci_failures.py
+++ b/scripts/retrieve_ci_failures.py
@@ -282,6 +282,48 @@ def diff_failure_vs_fix(repo, failure_commits, fix_commits):
         return None
 
 
+def process_diff(bug_id, obj, upload, repo_path):
+    diff_path = os.path.join("data", "ci_failures_diffs", f"{bug_id}.diff")
+    diff_zst_path = f"{diff_path}.zst"
+
+    if os.path.exists(diff_path) or os.path.exists(diff_zst_path):
+        return (0, 0)
+
+    if upload and utils.exists_s3(diff_zst_path):
+        return (0, 0)
+
+    try:
+        diff = diff_failure_vs_fix(
+            repo_path,
+            [
+                utils.hg2git(commit["node"])
+                for commit in obj["commits"]
+                if commit["backedoutby"]
+            ],
+            [
+                utils.hg2git(commit["node"])
+                for commit in obj["commits"]
+                if not commit["backedoutby"] and not commit["backsout"]
+            ],
+        )
+    except requests.exceptions.HTTPError as e:
+        logger.error("Failure mapping hg commit hash to git commit hash %s", e)
+        return (1, 0)
+
+    if diff is not None and len(diff) > 0:
+        with open(diff_path, "wb") as f:
+            f.write(diff)
+
+        utils.zstd_compress(diff_path)
+
+        os.remove(diff_path)
+
+        if upload:
+            utils.upload_s3([diff_zst_path])
+    else:
+        return (0, 1)
+
+
 def generate_diffs(repo_url, repo_path, fixed_by_commit_pushes, upload):
     if not os.path.exists(repo_path):
         for attempt in tenacity.Retrying(
@@ -298,48 +340,18 @@ def generate_diffs(repo_url, repo_path, fixed_by_commit_pushes, upload):
 
     diff_errors = 0
     mapping_errors = 0
-    for bug_id, obj in tqdm(
-        fixed_by_commit_pushes.items(), total=len(fixed_by_commit_pushes)
-    ):
-        diff_path = os.path.join("data", "ci_failures_diffs", f"{bug_id}.diff")
-        diff_zst_path = f"{diff_path}.zst"
-        if os.path.exists(diff_path) or os.path.exists(diff_zst_path):
-            continue
+    diffs = [(bug_id, obj) for bug_id, obj in fixed_by_commit_pushes.items()]
 
-        if upload and utils.exists_s3(diff_zst_path):
-            continue
-
-        try:
-            diff = diff_failure_vs_fix(
-                repo_path,
-                [
-                    utils.hg2git(commit["node"])
-                    for commit in obj["commits"]
-                    if commit["backedoutby"]
-                ],
-                [
-                    utils.hg2git(commit["node"])
-                    for commit in obj["commits"]
-                    if not commit["backedoutby"] and not commit["backsout"]
-                ],
-            )
-        except requests.exceptions.HTTPError as e:
-            logger.error("Failure mapping hg commit hash to git commit hash %s", e)
-            mapping_errors += 1
-            continue
-
-        if diff is not None and len(diff) > 0:
-            with open(diff_path, "wb") as f:
-                f.write(diff)
-
-            utils.zstd_compress(diff_path)
-
-            os.remove(diff_path)
+    with ThreadPoolExecutor() as executor:
+        futures = [
+            executor.submit(process_diff, bug_id, obj, upload, repo_path)
+            for bug_id, obj in diffs
+        ]
 
-            if upload:
-                utils.upload_s3([diff_zst_path])
-        else:
-            diff_errors += 1
+    for future in tqdm(as_completed(futures), totla=len(futures)):
+        mapping_error, diff_error = future.result()
+        mapping_errors += mapping_error
+        diff_errors += diff_error
 
     logger.info(f"Failed mapping {mapping_errors} hashes")
     logger.info(f"Failed generating {diff_errors} diffs")