diff --git a/server/migrations/20210916123647_add_nonce_to_channel_messages.sql b/server/migrations/20210916123647_add_nonce_to_channel_messages.sql
new file mode 100644
index 0000000000..ee4d4aa319
--- /dev/null
+++ b/server/migrations/20210916123647_add_nonce_to_channel_messages.sql
@@ -0,0 +1,4 @@
+ALTER TABLE "channel_messages"
+ADD "nonce" UUID NOT NULL DEFAULT gen_random_uuid();
+
+CREATE UNIQUE INDEX "index_channel_messages_nonce" ON "channel_messages" ("nonce");