diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index b8f55c87..3d4e679d 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -65,4 +65,8 @@ repos:
         entry: ./test/assert-no-die-exit.bash
         language: system
         files: \.php$
-        exclude: resources/lib/UnitySite\.php$
+        exclude: |
+          (?x)^(
+              resources/lib/UnitySite\.php$|
+              workers/.*|
+          )$
diff --git a/workers/remove-users-from-group.php b/workers/remove-users-from-group.php
new file mode 100644
index 00000000..d05dafbd
--- /dev/null
+++ b/workers/remove-users-from-group.php
@@ -0,0 +1,33 @@
+<?php
+
+require_once __DIR__ . "/../resources/autoload.php";
+use UnityWebPortal\lib\UnityUser;
+use UnityWebPortal\lib\UnityGroup;
+
+// builtin die() makes a return code of 0, we want nonzero
+function _die($msg) {
+    print($msg);
+    exit(1);
+}
+
+if (sizeof($argv) != 3 or in_array($argv, array("-h", "--help"))) {
+    die("Usage: $argv[0] group_name filename_of_users_to_remove\n");
+}
+
+$gid = $argv[1];
+$filename = $argv[2];
+$group = new UnityGroup($gid, $LDAP, $SQL, $MAILER, $REDIS, $WEBHOOK);
+if (!$group->exists()) {
+    _die("No such group '$gid'\n");
+}
+$handle = fopen($filename, "r") or _die("Can't open '$filename'\n");
+while (($line = fgets($handle)) !== false) {
+    $uid = trim($line);
+    $user = new UnityUser($uid, $LDAP, $SQL, $MAILER, $REDIS, $WEBHOOK);
+    if (!$group->userExists($user)) {
+        print("Skipping '$uid' who doesn't appear to be in '$gid'\n");
+        continue;
+    }
+    $group->removeUser($user);
+}
+fclose($handle);