diff --git a/graph-info.rkt b/graph-info.rkt
new file mode 100644
index 0000000..f108af9
--- /dev/null
+++ b/graph-info.rkt
@@ -0,0 +1,43 @@
+#lang racket
+
+(provide (struct-out graph-info)
+         (struct-out node-info)
+         (struct-out field-info)
+         (struct-out rich-graph-info)
+         (struct-out rich-mapping-info))
+
+(struct graph-info (name
+                    multi-constructor
+                    root
+                    node-order
+                    nodes))
+(struct node-info (constructor
+                   predicate?
+                   field-order
+                   fields
+                   promise-type
+                   make-incomplete-type  ;; may be removed later
+                   incomplete-type
+                   make-placeholder-type ;; may be removed later.
+                   placeholder-type))
+(struct field-info (type
+                    incomplete-type))
+
+(struct rich-graph-info (name
+                         multi-constructor
+                         root-node
+                         root-mapping
+                         node-order
+                         nodes
+                         mapping-order
+                         mappings))
+(struct rich-mapping-info (constructor
+                           ;predicate?
+                           ;field-order
+                           ;fields
+                           with-promises-type
+                           ;make-incomplete-type  ;; may be removed later
+                           ;incomplete-type
+                           ;make-placeholder-type ;; may be removed later.
+                           ;placeholder-type
+                           ))
\ No newline at end of file
diff --git a/graph.hl.rkt b/graph.hl.rkt
new file mode 100644
index 0000000..792d757
--- /dev/null
+++ b/graph.hl.rkt
@@ -0,0 +1,109 @@
+#lang hyper-literate typed/racket/base #:no-auto-require
+@(require racket/require
+          scribble-enhanced/doc
+          racket/require
+          hyper-literate
+          (subtract-in scribble/struct scribble-enhanced/doc)
+          scribble/decode
+          (for-label racket/format
+                     racket/promise
+                     racket/list
+                     type-expander
+                     (except-in (subtract-in typed/racket/base type-expander)
+                                values)
+                     (only-in racket/base values)
+                     (subtract-in racket/contract typed/racket/base)
+                     phc-toolkit
+                     phc-toolkit/untyped-only
+                     remember))
+@(unless-preexpanding
+  (require (for-label (submod ".."))))
+@doc-lib-setup
+
+@chunk[<graph>
+       (define-syntax define-graph
+         (syntax-parser
+           [<signature>
+            <implementation>]))]
+
+@chunk[<signature>
+       (_ _name
+          [[_nodeᵢ [_fieldᵢⱼ :colon _τᵢⱼ] …] …]
+          [[(_mappingₖ [_argₖₗ _τₖₗ] …) :colon _return-typeₖ . _bodyₖ] …])]
+
+@chunk[<implementation>
+       #'()]
+
+@section{Overview of the implementation (draft)}
+
+@chunk[<implementation-draft>
+       <create-Qₖ>
+       <re-bind-mappings>
+       <define-indices>
+       <process-queues>]
+
+@chunk[<define-indices>
+       (define/with-syntax (_indexₖ …) (stx-map gensym #'(_idxₖ …)))
+       #'(begin
+           (define-type _indexₖ (graph-index '_indexₖ))
+           …)]
+
+@chunk[<define-index>
+       (struct (K) graph-index ([key : K] [index : Index]))]
+
+Create one queue @racket[_Qₖ] for each mapping:
+
+@chunk[<create-Qₖ>
+       #'(begin
+           (define _Qₖ <create-queue>)
+           (define _Qₖ-enqueue <TODO>)
+           (define _Qₖ-pop <TODO>)
+           …)]
+
+Re-bind mappings to catch outbound calls:
+
+@chunk[<re-bind-mappings>
+       #'(let ([_mappingₖ _make-placeholderₖ] …)
+           . bodyₖ)]
+
+Define functions which enqueue into a given @racket[_Qₖ] and start processing.
+The final @racket[_name] macro dispatches to these functions.
+
+@chunk[<entry-pointₖ>
+       #'(begin
+           (define (_entry-pointₖ _argₖₗ …)
+             (entry-point #:mappingₖ (list (list _argₖₗ …))))
+           …)]
+
+These are based upon the main @racket[entry-point], which takes any number of
+initial elements to enqueue, and processes the queues till they are all empty.
+
+@chunk[<entry-point>
+       #'(define (entry-point #:mappingₖ [_argsₖ* : (Listof (List τₖₗ …)) '()])
+           (for ([_argsₖ (in-list _argsₖ*)])
+             (let-values ([(_argₖₗ …) _argsₖ])
+               (Qₖ-enqueue _argₖₗ …))))]
+
+@chunk[<process-queues>
+       (until queues are all empty
+              process item, see below)]
+
+@itemlist[
+ @item{Find and replace references to old nodes and new incomplete nodes and
+  new placeholder nodes, instead insert indices.}
+ @item{Problem: we need to actually insert indices for references to nodes,
+  not for references to mappings (those have to be inlined).}]
+
+
+@chunk[<*>
+       (require racket/require
+                (for-syntax (subtract-in (combine-in racket/base
+                                                     syntax/parse)
+                                         "subtemplate-override.rkt")
+                            phc-toolkit/untyped
+                            type-expander/expander
+                            "subtemplate-override.rkt")
+                "traversal.hl.rkt"
+                phc-toolkit)
+       <define-index>
+       <graph>]
\ No newline at end of file
diff --git a/info.rkt b/info.rkt
index 8e448be..38c4ad8 100644
--- a/info.rkt
+++ b/info.rkt
@@ -14,7 +14,8 @@
 (define build-deps '("scribble-lib"
                      "racket-doc"
                      "remember"
-                     "typed-racket-doc"))
+                     "typed-racket-doc"
+                     "aful"))
 (define scribblings
   '(("scribblings/phc-graph.scrbl" ()
                                    ("Data Structures"))