diff --git a/src/pg.ml b/src/pg.ml
index 305672db..31c67d71 100644
--- a/src/pg.ml
+++ b/src/pg.ml
@@ -1,10 +1,12 @@
+(* TODO
+   how to fix postgres/caqti tuple type?
+   need to add boilerplate in each query for amounts *)
+
 open Crypto
 
 module Caqti_type = struct
   include Caqti_type
 
-  (* TODO add a dune stanza like for prelude:
-     "(flags (:standard -open Prelude))" *)
   (* we want to use int64 timestamps,
      not postgresql built-in timestamp type *)
   let ptime : Ptime.t option t = Timestamp.caqti