diff --git a/sledge/lib/import/import.ml b/sledge/lib/import/import.ml
index d966aa860..f2111e1ea 100644
--- a/sledge/lib/import/import.ml
+++ b/sledge/lib/import/import.ml
@@ -30,6 +30,7 @@ exception Not_found = Caml.Not_found
 include Stdio
 module Command = Core.Command
 module Hash_queue = Core_kernel.Hash_queue
+include Import0
 
 (** Tuple operations *)
 
@@ -45,11 +46,6 @@ let ( $ ) f g x = f x ; g x
 let ( $> ) x f = f x ; x
 let ( <$ ) f x = f x ; x
 
-(** Pretty-printing *)
-
-type 'a pp = Formatter.t -> 'a -> unit
-type ('a, 'b) fmt = ('a, 'b) Trace.fmt
-
 (** Failures *)
 
 let fail = Trace.fail
@@ -135,20 +131,6 @@ let filter_map_preserving_phys_equal filter_map t ~f =
   in
   if !change then t' else t
 
-module type Applicative_syntax = sig
-  type 'a t
-
-  val ( let+ ) : 'a t -> ('a -> 'b) -> 'b t
-  val ( and+ ) : 'a t -> 'b t -> ('a * 'b) t
-end
-
-module type Monad_syntax = sig
-  include Applicative_syntax
-
-  val ( let* ) : 'a t -> ('a -> 'b t) -> 'b t
-  val ( and* ) : 'a t -> 'b t -> ('a * 'b) t
-end
-
 module Option = struct
   include Base.Option
 
diff --git a/sledge/lib/import/import.mli b/sledge/lib/import/import.mli
index feb2bb099..0609a4f20 100644
--- a/sledge/lib/import/import.mli
+++ b/sledge/lib/import/import.mli
@@ -29,6 +29,7 @@ external ( != ) : 'a -> 'a -> bool = "%noteq"
 include module type of Stdio
 module Command = Core.Command
 module Hash_queue = Core_kernel.Hash_queue
+include module type of Import0
 
 (** Tuple operations *)
 
@@ -63,14 +64,6 @@ val ( <$ ) : ('a -> unit) -> 'a -> 'a
 (** Apply and ignore function: [f <$ x] is exactly equivalent to [f x ; x].
     Left associative. *)
 
-(** Pretty-printing *)
-
-(** Pretty-printer for argument type. *)
-type 'a pp = Formatter.t -> 'a -> unit
-
-(** Format strings. *)
-type ('a, 'b) fmt = ('a, 'b) Trace.fmt
-
 (** Failures *)
 
 exception Unimplemented of string
@@ -110,20 +103,6 @@ val or_error : ('a -> 'b) -> 'a -> unit -> 'b or_error
 
 module Invariant : module type of Base.Invariant
 
-module type Applicative_syntax = sig
-  type 'a t
-
-  val ( let+ ) : 'a t -> ('a -> 'b) -> 'b t
-  val ( and+ ) : 'a t -> 'b t -> ('a * 'b) t
-end
-
-module type Monad_syntax = sig
-  include Applicative_syntax
-
-  val ( let* ) : 'a t -> ('a -> 'b t) -> 'b t
-  val ( and* ) : 'a t -> 'b t -> ('a * 'b) t
-end
-
 module Option : sig
   include module type of Base.Option
 
diff --git a/sledge/lib/import/import0.ml b/sledge/lib/import/import0.ml
new file mode 100644
index 000000000..b77e48dac
--- /dev/null
+++ b/sledge/lib/import/import0.ml
@@ -0,0 +1,28 @@
+(*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+(** Pretty-printer for argument type. *)
+type 'a pp = Format.formatter -> 'a -> unit
+
+(** Format strings. *)
+type ('a, 'b) fmt = ('a, 'b) Trace.fmt
+
+module Sexp = Sexplib.Sexp
+
+module type Applicative_syntax = sig
+  type 'a t
+
+  val ( let+ ) : 'a t -> ('a -> 'b) -> 'b t
+  val ( and+ ) : 'a t -> 'b t -> ('a * 'b) t
+end
+
+module type Monad_syntax = sig
+  include Applicative_syntax
+
+  val ( let* ) : 'a t -> ('a -> 'b t) -> 'b t
+  val ( and* ) : 'a t -> 'b t -> ('a * 'b) t
+end