.

go/zodb/db.go

@@ -55,7 +55,7 @@ type DB struct {
 	δtail ΔTail // [](rev↑, []oid)
 
 	// openers waiting for δtail.Head to become covering their at.
-	δwait map[δwaiter]struct{} // set(at, ready)
+	δwait map[δwaiter]struct{} // set{(at, ready)}
 }
 
 // δwaiter represents someone waiting for δtail.Head to become ≥ at.

go/zodb/open.go

@@ -205,6 +205,9 @@ func (s *storage) watcher() {
 				return
 			}
 
+			// XXX verify event.Tid ↑  (else e.g. δtail.Append will panic)
+			//     if !↑ - stop the storage with error.
+
 			// deliver event to all watchers
 			for watchq := range s.watchTab {
 				watchq <- event