From 19d07bd4af86d6dad71f29bcc5b8e5f97704aef2 Mon Sep 17 00:00:00 2001
From: Benoit Chesneau <bchesneau@gmail.com>
Date: Fri, 23 Jan 2026 11:02:29 +0100
Subject: [PATCH] fix: print exception to stderr on worker boot failure

When a worker fails to boot, the exception is now printed to stderr
(in addition to being logged), consistent with AppImportError handling.
This makes boot failures more visible to users.

Closes #2933
---
 gunicorn/arbiter.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gunicorn/arbiter.py b/gunicorn/arbiter.py
index 9b9c8d6d..8e27dca4 100644
--- a/gunicorn/arbiter.py
+++ b/gunicorn/arbiter.py
@@ -631,8 +631,10 @@ class Arbiter:
             print("%s" % e, file=sys.stderr)
             sys.stderr.flush()
             sys.exit(self.APP_LOAD_ERROR)
-        except Exception:
+        except Exception as e:
             self.log.exception("Exception in worker process")
+            print("%s" % e, file=sys.stderr)
+            sys.stderr.flush()
             if not worker.booted:
                 sys.exit(self.WORKER_BOOT_ERROR)
             sys.exit(-1)