create typed timestate driver wrapper

racket/typed/drivers/timestate.rkt

@@ -0,0 +1,22 @@
+#lang typed/syndicate/roles
+
+(provide activate!
+         later-than
+         LaterThanT
+         LaterThan
+         TimeStateDriver)
+
+(require-struct later-than
+                #:as LaterThanT
+                #:from syndicate/drivers/timestate)
+
+(define-type-alias LaterThan (LaterThanT Int))
+
+(define-type-alias TimeStateDriver
+  (U LaterThan
+     (Observe (LaterThanT ★/t))))
+
+;; TODO ignoring other driver underneath it
+
+(require/typed (submod syndicate/drivers/timestate syndicate-main)
+  [activate! : (proc → ⊥ #:spawns ((Actor TimeStateDriver)))])