diff --git a/example-models/example-docker.conf b/example-models/example-docker.conf
index f26ab0a..d39eb63 100644
--- a/example-models/example-docker.conf
+++ b/example-models/example-docker.conf
@@ -3,7 +3,10 @@
     listen  => ['http://*:3000'],
     trusted_proxies => ['10.0/8', '127.0.0.1'],
     proxy => 1,
-    pid_file => 'derekovecs-example.'. `hostname -s | tr -d "\n"` .'.pid',
+    # In /tmp, not in the working directory: the image is built so that it can
+    # run as any user, which is what an NFS export with root_squash needs, and
+    # /derekovecs is only writable by root.
+    pid_file => '/tmp/derekovecs-example.'. `hostname -s | tr -d "\n"` .'.pid',
     workers => 4
   },