diff --git a/ops/db-bootstrap/set_tradein_fdw_password.sql b/ops/db-bootstrap/set_tradein_fdw_password.sql
index c0742ab2..0daf946a 100644
--- a/ops/db-bootstrap/set_tradein_fdw_password.sql
+++ b/ops/db-bootstrap/set_tradein_fdw_password.sql
@@ -10,18 +10,26 @@
 -- Combined with the regex whitelist on the backend side (fdw.py _PASSWORD_RE)
 -- this gives defense-in-depth.
 --
--- Extracted from deploy.yml inline DO block (PR #493 deploy/1156 incident).
--- The original block used multi-line backslash continuations inside a double-quoted
--- bash string with $$-dollar-quoting + psql variable substitution — fragile escaping
--- that likely caused the bootstrap step to fail before `compose up -d` ran.
--- Using `-f <file>` with psql-native variable substitution via `-v pw=` is safe.
+-- psql variable substitution (:'pw') НЕ интерполируется внутри dollar-quoted
+-- блока ($$...$$) — это правило psql, не bug. Поэтому password передаём в DO
+-- через сессионный GUC (set_config), который psql интерполирует ВНЕ dollar
+-- quote, и читаем внутри через current_setting().
+-- Reference incident: deploy 2026-05-24 (post-merge PR #503) упал на
+-- "syntax error at or near ':'" в LINE 4 этого файла — :'pw' дошёл до сервера
+-- as literal вместо интерполяции.
+
+SELECT set_config('app.fdw_pw', :'pw', false);
 
 DO $$
 BEGIN
   IF EXISTS (SELECT 1 FROM pg_roles WHERE rolname = 'tradein_fdw_reader') THEN
-    EXECUTE format('ALTER ROLE tradein_fdw_reader WITH PASSWORD %L', :'pw');
+    EXECUTE format('ALTER ROLE tradein_fdw_reader WITH PASSWORD %L', current_setting('app.fdw_pw'));
     RAISE NOTICE 'tradein_fdw_reader password set';
   ELSE
     RAISE NOTICE 'tradein_fdw_reader role missing — migration 100_tradein_fdw_role.sql not applied yet';
   END IF;
 END $$;
+
+-- Clear GUC after use (defense-in-depth — не оставляем password в session state
+-- даже на short connection).
+SELECT set_config('app.fdw_pw', '', false);