migrations/0007_processed_events.sql | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/migrations/0007_processed_events.sql b/migrations/0007_processed_events.sql
new file mode 100644
index 0000000..fd3b81f
--- /dev/null
+++ b/migrations/0007_processed_events.sql
@@ -0,0 +1,7 @@
+CREATE TABLE processed_events (
+    event_id text PRIMARY KEY,
+    processed_at timestamptz NOT NULL DEFAULT now()
+);
+
+-- one successful capture per order, whatever calls it
+CREATE UNIQUE INDEX captures_one_per_order ON captures (order_id) WHERE status = 'succeeded';