diff --git a/collects/typed-scheme/private/init-envs.ss b/collects/typed-scheme/env/init-envs.ss
similarity index 90%
rename from collects/typed-scheme/private/init-envs.ss
rename to collects/typed-scheme/env/init-envs.ss
index d0dac77c..4a03b910 100644
--- a/collects/typed-scheme/private/init-envs.ss
+++ b/collects/typed-scheme/env/init-envs.ss
@@ -1,11 +1,16 @@
 #lang scheme/base
 (provide (all-defined-out))
+(require "../utils/utils.ss")
 
-(require "type-env.ss" "type-rep.ss" "type-name-env.ss" "union.ss" "effect-rep.ss"
-         "type-effect-convenience.ss" "type-alias-env.ss"
-         "type-alias-env.ss")
-(require mzlib/pconvert scheme/match mzlib/shared
-         (for-template mzlib/pconvert mzlib/shared scheme/base "type-rep.ss" "union.ss" "effect-rep.ss"))    
+(require "type-env.ss" 
+	 "type-name-env.ss"
+	 (rep type-rep effect-rep)
+	 (for-template (rep type-rep effect-rep) 
+		       (private union)
+		       mzlib/pconvert mzlib/shared scheme/base)
+	 (private type-effect-convenience union)
+         "type-alias-env.ss"
+	 mzlib/pconvert scheme/match mzlib/shared)
 
 (define (initialize-type-name-env initial-type-names)
   (for-each (lambda (nm/ty) (register-resolved-type-alias (car nm/ty) (cadr nm/ty))) initial-type-names))
diff --git a/collects/typed-scheme/private/lexical-env.ss b/collects/typed-scheme/env/lexical-env.ss
similarity index 90%
rename from collects/typed-scheme/private/lexical-env.ss
rename to collects/typed-scheme/env/lexical-env.ss
index e5946a31..63a1295b 100644
--- a/collects/typed-scheme/private/lexical-env.ss
+++ b/collects/typed-scheme/env/lexical-env.ss
@@ -1,6 +1,12 @@
 #lang scheme/base
 
-(require "type-environments.ss" "tc-utils.ss" "type-env.ss" "mutated-vars.ss" "type-utils.ss" "type-effect-convenience.ss")
+(require (except-in "../utils/utils.ss" extend))
+(require "type-environments.ss" 
+	 (utils tc-utils)
+	 "type-env.ss"
+	 (private mutated-vars)
+	 (private type-utils)
+	 (private type-effect-convenience))
 
 (provide (all-defined-out))
 
diff --git a/collects/typed-scheme/private/type-alias-env.ss b/collects/typed-scheme/env/type-alias-env.ss
similarity index 96%
rename from collects/typed-scheme/private/type-alias-env.ss
rename to collects/typed-scheme/env/type-alias-env.ss
index 0be4da74..dd9183d3 100644
--- a/collects/typed-scheme/private/type-alias-env.ss
+++ b/collects/typed-scheme/env/type-alias-env.ss
@@ -1,7 +1,8 @@
 #lang scheme/base
 
+(require (except-in "../utils/utils.ss" extend))
 (require syntax/boundmap
-         "tc-utils.ss"
+         (utils tc-utils)
          mzlib/trace
          scheme/match)
 
diff --git a/collects/typed-scheme/private/type-env.ss b/collects/typed-scheme/env/type-env.ss
similarity index 95%
rename from collects/typed-scheme/private/type-env.ss
rename to collects/typed-scheme/env/type-env.ss
index d9dafeef..59eb3cad 100644
--- a/collects/typed-scheme/private/type-env.ss
+++ b/collects/typed-scheme/env/type-env.ss
@@ -1,7 +1,9 @@
 #lang scheme/base
 
+(require (except-in "../utils/utils.ss" extend))
 (require syntax/boundmap
-         "tc-utils.ss" "type-utils.ss")
+         (utils tc-utils)
+	 (private type-utils))
 
 (provide register-type
          finish-register-type
diff --git a/collects/typed-scheme/private/type-environments.ss b/collects/typed-scheme/env/type-environments.ss
similarity index 96%
rename from collects/typed-scheme/private/type-environments.ss
rename to collects/typed-scheme/env/type-environments.ss
index 536fdfc9..0f159ec0 100644
--- a/collects/typed-scheme/private/type-environments.ss
+++ b/collects/typed-scheme/env/type-environments.ss
@@ -10,8 +10,9 @@
          initial-tvar-env
          with-dotted-env/extend)
 
+(require (prefix-in r: "../utils/utils.ss"))
 (require scheme/match
-         "tc-utils.ss")
+         (r:utils tc-utils))
 
 ;; eq? has the type of equal?, and l is an alist (with conses!)
 (define-struct env (eq? l))
diff --git a/collects/typed-scheme/private/type-name-env.ss b/collects/typed-scheme/env/type-name-env.ss
similarity index 93%
rename from collects/typed-scheme/private/type-name-env.ss
rename to collects/typed-scheme/env/type-name-env.ss
index 370b77e7..d6773f0e 100644
--- a/collects/typed-scheme/private/type-name-env.ss
+++ b/collects/typed-scheme/env/type-name-env.ss
@@ -1,9 +1,10 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
 (require syntax/boundmap
          mzlib/trace
-         "tc-utils.ss"
-         "type-utils.ss")
+         (utils tc-utils)
+         (private type-utils))
 
 (provide register-type-name
          lookup-type-name
diff --git a/collects/typed-scheme/private/constraint-structs.ss b/collects/typed-scheme/infer/constraint-structs.ss
similarity index 94%
rename from collects/typed-scheme/private/constraint-structs.ss
rename to collects/typed-scheme/infer/constraint-structs.ss
index def84ae0..d5c97034 100644
--- a/collects/typed-scheme/private/constraint-structs.ss
+++ b/collects/typed-scheme/infer/constraint-structs.ss
@@ -1,6 +1,7 @@
 #lang scheme/base
 
-(require "type-rep.ss"
+(require (except-in "../utils/utils.ss" extend))
+(require (rep type-rep)
          scheme/contract)
 
 ;; S, T types
diff --git a/collects/typed-scheme/private/constraints.ss b/collects/typed-scheme/infer/constraints.ss
similarity index 94%
rename from collects/typed-scheme/private/constraints.ss
rename to collects/typed-scheme/infer/constraints.ss
index 2697109e..3dff2c08 100644
--- a/collects/typed-scheme/private/constraints.ss
+++ b/collects/typed-scheme/infer/constraints.ss
@@ -1,8 +1,9 @@
 #lang scheme/unit
 
-(require "type-effect-convenience.ss" "type-rep.ss" 
-         "type-utils.ss" "union.ss" "tc-utils.ss" 
-         "subtype.ss" "utils.ss"
+(require (except-in "../utils/utils.ss" extend))
+(require (private type-effect-convenience type-utils union subtype)
+	 (rep type-rep)
+	 (utils tc-utils)
          "signatures.ss" "constraint-structs.ss"
          scheme/match)
 
diff --git a/collects/typed-scheme/private/dmap.ss b/collects/typed-scheme/infer/dmap.ss
similarity index 92%
rename from collects/typed-scheme/private/dmap.ss
rename to collects/typed-scheme/infer/dmap.ss
index ef2112ba..95926680 100644
--- a/collects/typed-scheme/private/dmap.ss
+++ b/collects/typed-scheme/infer/dmap.ss
@@ -1,6 +1,8 @@
 #lang scheme/unit
 
-(require "signatures.ss" "utils.ss" "tc-utils.ss" "constraint-structs.ss"
+(require (except-in "../utils/utils.ss" extend))
+(require "signatures.ss" "constraint-structs.ss"
+	 (utils tc-utils)
          scheme/match)
 
 (import constraints^)
diff --git a/collects/typed-scheme/private/infer-unit.ss b/collects/typed-scheme/infer/infer-unit.ss
similarity index 98%
rename from collects/typed-scheme/private/infer-unit.ss
rename to collects/typed-scheme/infer/infer-unit.ss
index b9590895..c640d363 100644
--- a/collects/typed-scheme/private/infer-unit.ss
+++ b/collects/typed-scheme/infer/infer-unit.ss
@@ -1,12 +1,14 @@
 #lang scheme/unit
 
-(require "type-effect-convenience.ss" "type-rep.ss" "effect-rep.ss" "rep-utils.ss"
-         "free-variance.ss" 
-         (except-in "type-utils.ss" Dotted)
-         "union.ss" "tc-utils.ss" "type-name-env.ss"
-         "subtype.ss" "remove-intersect.ss" "signatures.ss" "utils.ss"
+(require (except-in "../utils/utils.ss"))
+(require (rep free-variance type-rep effect-rep rep-utils)
+	 (private type-effect-convenience union subtype remove-intersect)
+	 (utils tc-utils)
+	 (env type-name-env)
+         (except-in (private type-utils) Dotted)
          "constraint-structs.ss"
-         (only-in "type-environments.ss" lookup current-tvars)
+	 "signatures.ss"
+         (only-in (env type-environments) lookup current-tvars)
          scheme/match
          mzlib/etc
          mzlib/trace
diff --git a/collects/typed-scheme/private/infer.ss b/collects/typed-scheme/infer/infer.ss
similarity index 67%
rename from collects/typed-scheme/private/infer.ss
rename to collects/typed-scheme/infer/infer.ss
index d860e5f5..208943a3 100644
--- a/collects/typed-scheme/private/infer.ss
+++ b/collects/typed-scheme/infer/infer.ss
@@ -1,9 +1,10 @@
 #lang scheme/base
 
+(require (except-in "../utils/utils.ss" infer))
 (require "infer-unit.ss" "constraints.ss" "dmap.ss" "signatures.ss"
          "restrict.ss" "promote-demote.ss"
          (only-in scheme/unit provide-signature-elements)
-         "unit-utils.ss")
+         (utils unit-utils))
          
 (provide-signature-elements restrict^ infer^)
 
diff --git a/collects/typed-scheme/private/promote-demote.ss b/collects/typed-scheme/infer/promote-demote.ss
similarity index 96%
rename from collects/typed-scheme/private/promote-demote.ss
rename to collects/typed-scheme/infer/promote-demote.ss
index d24eda82..87051229 100644
--- a/collects/typed-scheme/private/promote-demote.ss
+++ b/collects/typed-scheme/infer/promote-demote.ss
@@ -1,8 +1,9 @@
 #lang scheme/unit
 
-(require "type-effect-convenience.ss" "type-rep.ss" 
-         "type-utils.ss" "union.ss" 
-         "signatures.ss" "utils.ss"
+(require "../utils/utils.ss")
+(require (rep type-rep)
+	 (private type-effect-convenience union type-utils)
+         "signatures.ss"
          scheme/list)
 
 (import)
diff --git a/collects/typed-scheme/private/restrict.ss b/collects/typed-scheme/infer/restrict.ss
similarity index 90%
rename from collects/typed-scheme/private/restrict.ss
rename to collects/typed-scheme/infer/restrict.ss
index 2c86a687..e1365605 100644
--- a/collects/typed-scheme/private/restrict.ss
+++ b/collects/typed-scheme/infer/restrict.ss
@@ -1,8 +1,8 @@
 #lang scheme/unit
 
-(require "type-rep.ss" 
-         "type-utils.ss" "union.ss" 
-         "subtype.ss" "remove-intersect.ss" 
+(require "../utils/utils.ss")
+(require (rep type-rep)
+	 (private type-utils union remove-intersect subtype)
          "signatures.ss"
          scheme/match)
 
diff --git a/collects/typed-scheme/infer/signatures.ss b/collects/typed-scheme/infer/signatures.ss
new file mode 100644
index 00000000..6db02b38
--- /dev/null
+++ b/collects/typed-scheme/infer/signatures.ss
@@ -0,0 +1,29 @@
+#lang scheme/base
+(require scheme/unit)
+(provide (all-defined-out))
+
+(define-signature dmap^
+  (dmap-meet))
+
+(define-signature promote-demote^
+  (var-promote var-demote))
+
+(define-signature constraints^
+  (exn:infer?
+   fail-sym
+   ;; inference failure - masked before it gets to the user program
+   (define-syntaxes (fail!)
+     (syntax-rules ()
+       [(_ s t) (raise fail-sym)]))
+   cset-meet cset-meet*
+   no-constraint
+   empty-cset
+   insert
+   cset-combine
+   c-meet))
+
+(define-signature restrict^
+  (restrict))
+
+(define-signature infer^
+  (infer infer/vararg infer/dots))
diff --git a/collects/typed-scheme/private/base-env.ss b/collects/typed-scheme/private/base-env.ss
index 5703eb4f..719c25ba 100644
--- a/collects/typed-scheme/private/base-env.ss
+++ b/collects/typed-scheme/private/base-env.ss
@@ -3,6 +3,7 @@
 ;; these are libraries providing functions we add types to that are not in scheme/base
 (require
  "extra-procs.ss"
+ "../utils/utils.ss"
  (only-in scheme/list cons? take drop add-between last filter-map)
  (only-in rnrs/lists-6 fold-left)
  '#%paramz
@@ -15,13 +16,12 @@
 ;; these are all for constructing the types given to variables
 (require (for-syntax
           scheme/base
-          "init-envs.ss"
-          "effect-rep.ss"
-          (except-in "type-rep.ss" make-arr)
+          (env init-envs)          
+          (except-in (rep effect-rep type-rep) make-arr)
           "type-effect-convenience.ss"
           (only-in "type-effect-convenience.ss" [make-arr* make-arr])
           "union.ss"
-          "tc-structs.ss"))
+          (typecheck tc-structs)))
 
 (define-for-syntax (initialize-others) 
   (d-s date 
diff --git a/collects/typed-scheme/private/base-types.ss b/collects/typed-scheme/private/base-types.ss
index cc4bb42a..6058fd4b 100644
--- a/collects/typed-scheme/private/base-types.ss
+++ b/collects/typed-scheme/private/base-types.ss
@@ -1,9 +1,10 @@
 #lang scheme/base
 
+(require (except-in "../utils/utils.ss" extend))
 (require (for-syntax
           scheme/base
-          "init-envs.ss"
-          (except-in "type-rep.ss" make-arr)
+          (env init-envs)
+          (except-in (rep type-rep) make-arr)
           "type-effect-convenience.ss"
           (only-in "type-effect-convenience.ss" [make-arr* make-arr])
           "union.ss"))
diff --git a/collects/typed-scheme/private/parse-type.ss b/collects/typed-scheme/private/parse-type.ss
index 0885e9c8..07adfd9e 100644
--- a/collects/typed-scheme/private/parse-type.ss
+++ b/collects/typed-scheme/private/parse-type.ss
@@ -2,16 +2,15 @@
 
 (provide parse-type parse-type/id)
 
-(require (except-in "type-rep.ss" make-arr)
+(require (except-in "../utils/utils.ss" extend))
+(require (except-in (rep type-rep) make-arr)
          "type-effect-convenience.ss"
          (only-in "type-effect-convenience.ss" [make-arr* make-arr])
-         "tc-utils.ss"
+         (utils tc-utils)
          "union.ss"
          syntax/stx
-         (except-in "type-environments.ss")
-         "type-name-env.ss"
-         "type-alias-env.ss"
-         "type-utils.ss"
+         (env type-environments type-name-env type-alias-env)
+	 "type-utils.ss"
          scheme/match)
 
 (define enable-mu-parsing (make-parameter #t))
diff --git a/collects/typed-scheme/private/prims.ss b/collects/typed-scheme/private/prims.ss
index ef3e7cc5..9068659c 100644
--- a/collects/typed-scheme/private/prims.ss
+++ b/collects/typed-scheme/private/prims.ss
@@ -22,20 +22,20 @@ This file defines two sorts of primitives. All of them are provided into any mod
 (provide (all-defined-out)
 	 (rename-out [define-typed-struct define-struct:]))
 
+(require (except-in "../utils/utils.ss" extend))
 (require (for-syntax 
           scheme/base
-          "type-rep.ss"
+          (rep type-rep)
           mzlib/match
           "parse-type.ss"
           syntax/struct
           syntax/stx
-          "utils.ss"
-          "tc-utils.ss"
-          "type-name-env.ss"
+	  (utils utils tc-utils)
+          (env type-name-env)
           "type-contract.ss"))
 
 (require "require-contract.ss"
-         "internal-forms.ss"
+         (typecheck internal-forms)
          (except-in mzlib/contract ->)
          (only-in mzlib/contract [-> c->])
          mzlib/struct
diff --git a/collects/typed-scheme/private/remove-intersect.ss b/collects/typed-scheme/private/remove-intersect.ss
index f9b273e8..d244fb73 100644
--- a/collects/typed-scheme/private/remove-intersect.ss
+++ b/collects/typed-scheme/private/remove-intersect.ss
@@ -1,7 +1,8 @@
 #lang scheme/base
 
-(require "type-rep.ss" "union.ss" "subtype.ss"
-         "type-utils.ss" "resolve-type.ss" "type-effect-convenience.ss"         
+(require (except-in "../utils/utils.ss" extend))
+(require (rep type-rep)
+	 (private union subtype resolve-type type-effect-convenience type-utils)
          mzlib/plt-match mzlib/trace)
 
 (provide (rename-out [*remove remove]) overlap)
diff --git a/collects/typed-scheme/private/resolve-type.ss b/collects/typed-scheme/private/resolve-type.ss
index d68de692..6526a428 100644
--- a/collects/typed-scheme/private/resolve-type.ss
+++ b/collects/typed-scheme/private/resolve-type.ss
@@ -1,6 +1,7 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
-(require "type-rep.ss"  "type-name-env.ss" "tc-utils.ss"
+(require (rep type-rep)  (env type-name-env) (utils tc-utils)
          "type-utils.ss"
          mzlib/plt-match
          mzlib/trace)
diff --git a/collects/typed-scheme/private/subtype.ss b/collects/typed-scheme/private/subtype.ss
index 3667f421..1db8c33b 100644
--- a/collects/typed-scheme/private/subtype.ss
+++ b/collects/typed-scheme/private/subtype.ss
@@ -1,12 +1,13 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
-(require (except-in "type-rep.ss" sub-eff) "type-utils.ss"
-         "tc-utils.ss"
-         "effect-rep.ss"
+(require (except-in (rep type-rep effect-rep) sub-eff)
+         (utils tc-utils)
+	 "type-utils.ss"
          "type-comparison.ss"
          "resolve-type.ss"
-         "type-name-env.ss"
-         (only-in "infer-dummy.ss" unify)
+         (env type-name-env)
+         (only-in (infer infer-dummy) unify)
          mzlib/plt-match
          mzlib/trace)
 
diff --git a/collects/typed-scheme/private/type-annotation.ss b/collects/typed-scheme/private/type-annotation.ss
index 1a72e73b..bbb83034 100644
--- a/collects/typed-scheme/private/type-annotation.ss
+++ b/collects/typed-scheme/private/type-annotation.ss
@@ -1,7 +1,11 @@
 #lang scheme/base
 
-(require "type-rep.ss" "parse-type.ss" "tc-utils.ss" "subtype.ss" "utils.ss"
-         "type-env.ss" "type-effect-convenience.ss" "resolve-type.ss" "union.ss"
+(require (except-in "../utils/utils.ss" extend))
+(require (rep type-rep)
+	 (utils tc-utils)
+	 (env type-env)
+	 "parse-type.ss" "subtype.ss"
+         "type-effect-convenience.ss" "resolve-type.ss" "union.ss"
          scheme/match mzlib/trace)
 (provide type-annotation
          get-type
diff --git a/collects/typed-scheme/private/type-effect-convenience.ss b/collects/typed-scheme/private/type-effect-convenience.ss
index 0eb73bcd..13aa199c 100644
--- a/collects/typed-scheme/private/type-effect-convenience.ss
+++ b/collects/typed-scheme/private/type-effect-convenience.ss
@@ -1,13 +1,14 @@
 #lang scheme/base  
-(require "type-rep.ss" 
-         "effect-rep.ss"
+(require "../utils/utils.ss")
+
+(require (rep type-rep effect-rep)
+         (utils tc-utils)
          scheme/match
          "type-comparison.ss"
          "type-effect-printer.ss"
          "union.ss"
          "subtype.ss"
          "type-utils.ss" 
-         "tc-utils.ss"
          scheme/promise
          (for-syntax macro-debugger/stxclass/stxclass)
          (for-syntax scheme/base))
diff --git a/collects/typed-scheme/private/type-effect-printer.ss b/collects/typed-scheme/private/type-effect-printer.ss
index 72038bb8..812f58a6 100644
--- a/collects/typed-scheme/private/type-effect-printer.ss
+++ b/collects/typed-scheme/private/type-effect-printer.ss
@@ -1,5 +1,9 @@
 #lang scheme/base
-(require "type-rep.ss" "effect-rep.ss" "rep-utils.ss" "tc-utils.ss" "planet-requires.ss" scheme/match)
+
+(require "../utils/utils.ss")
+(require (rep type-rep effect-rep rep-utils)
+	 (utils planet-requires tc-utils)
+	 scheme/match)
 
 ;; do we attempt to find instantiations of polymorphic types to print? 
 ;; FIXME - currently broken
diff --git a/collects/typed-scheme/private/type-utils.ss b/collects/typed-scheme/private/type-utils.ss
index 9c53cfa0..d74c89e0 100644
--- a/collects/typed-scheme/private/type-utils.ss
+++ b/collects/typed-scheme/private/type-utils.ss
@@ -1,10 +1,10 @@
 #lang scheme/base
 
-(require "type-rep.ss"
-         "effect-rep.ss"
-         "tc-utils.ss"
-         "rep-utils.ss"
-         (only-in "free-variance.ss" combine-frees)
+(require "../utils/utils.ss")
+
+(require (rep type-rep effect-rep rep-utils)
+         (utils tc-utils)
+         (only-in (rep free-variance) combine-frees)
          mzlib/plt-match
          scheme/list
          mzlib/trace
diff --git a/collects/typed-scheme/private/union.ss b/collects/typed-scheme/private/union.ss
index 02a1a271..d2235d65 100644
--- a/collects/typed-scheme/private/union.ss
+++ b/collects/typed-scheme/private/union.ss
@@ -1,7 +1,11 @@
 #lang scheme/base
 
-(require "type-rep.ss" "subtype.ss" "tc-utils.ss"
-         "type-effect-printer.ss" "rep-utils.ss"
+(require "../utils/utils.ss")
+
+(require (rep type-rep rep-utils)
+	 (utils tc-utils)
+	 "subtype.ss" 
+         "type-effect-printer.ss" 
          "type-comparison.ss"
          scheme/match mzlib/trace)
 
diff --git a/collects/typed-scheme/private/effect-rep.ss b/collects/typed-scheme/rep/effect-rep.ss
similarity index 100%
rename from collects/typed-scheme/private/effect-rep.ss
rename to collects/typed-scheme/rep/effect-rep.ss
diff --git a/collects/typed-scheme/private/free-variance.ss b/collects/typed-scheme/rep/free-variance.ss
similarity index 98%
rename from collects/typed-scheme/private/free-variance.ss
rename to collects/typed-scheme/rep/free-variance.ss
index 8d476558..7e4014e3 100644
--- a/collects/typed-scheme/private/free-variance.ss
+++ b/collects/typed-scheme/rep/free-variance.ss
@@ -1,7 +1,8 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
 (require (for-syntax scheme/base)
-         "tc-utils.ss"
+         (utils tc-utils)
          mzlib/etc)
 
 ;; this file contains support for calculating the free variables/indexes of types
diff --git a/collects/typed-scheme/private/interning.ss b/collects/typed-scheme/rep/interning.ss
similarity index 100%
rename from collects/typed-scheme/private/interning.ss
rename to collects/typed-scheme/rep/interning.ss
diff --git a/collects/typed-scheme/private/rep-utils.ss b/collects/typed-scheme/rep/rep-utils.ss
similarity index 98%
rename from collects/typed-scheme/private/rep-utils.ss
rename to collects/typed-scheme/rep/rep-utils.ss
index cd1d21b5..2f49dba9 100644
--- a/collects/typed-scheme/private/rep-utils.ss
+++ b/collects/typed-scheme/rep/rep-utils.ss
@@ -1,18 +1,18 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
 (require mzlib/struct 
          mzlib/plt-match
          syntax/boundmap
-         "planet-requires.ss"
+         (utils planet-requires)
          "free-variance.ss"
-         "utils.ss"
          "interning.ss"
          mzlib/etc
          (for-syntax 
           scheme/base
           syntax/struct
           syntax/stx
-          "utils.ss"))
+          (utils utils)))
 
 (provide == dt de print-type* print-effect* Type Type? Effect Effect? defintern hash-id Type-seq Effect-seq)
 
diff --git a/collects/typed-scheme/private/type-rep.ss b/collects/typed-scheme/rep/type-rep.ss
similarity index 99%
rename from collects/typed-scheme/private/type-rep.ss
rename to collects/typed-scheme/rep/type-rep.ss
index 889d0dd5..9ced9791 100644
--- a/collects/typed-scheme/private/type-rep.ss
+++ b/collects/typed-scheme/rep/type-rep.ss
@@ -1,7 +1,8 @@
 #lang scheme/base
+(require "../utils/utils.ss")
 
-(require "planet-requires.ss" "rep-utils.ss" "effect-rep.ss" "tc-utils.ss"
-         "free-variance.ss"
+(require (utils planet-requires tc-utils) 
+	 "rep-utils.ss" "effect-rep.ss" "free-variance.ss"
          mzlib/trace scheme/match
          (for-syntax scheme/base))
 
diff --git a/collects/typed-scheme/private/check-subforms-unit.ss b/collects/typed-scheme/typecheck/check-subforms-unit.ss
similarity index 92%
rename from collects/typed-scheme/private/check-subforms-unit.ss
rename to collects/typed-scheme/typecheck/check-subforms-unit.ss
index 554bbea1..e37c6f37 100644
--- a/collects/typed-scheme/private/check-subforms-unit.ss
+++ b/collects/typed-scheme/typecheck/check-subforms-unit.ss
@@ -1,15 +1,12 @@
 #lang scheme/unit
 
+(require (except-in "../utils/utils.ss" extend))
 (require syntax/kerncase
          scheme/match
          "signatures.ss"
-         "type-utils.ss"
-         "type-rep.ss" ;; doesn't need tests
-         "type-effect-convenience.ss" ;; maybe needs tests
-         "union.ss"
-         "subtype.ss" ;; has tests
-         "tc-utils.ss" ;; doesn't need tests
-         )
+         (private type-utils type-effect-convenience union subtype)
+	 (utils tc-utils)
+	 (rep type-rep))
 
 (import tc-if^ tc-lambda^ tc-app^ tc-let^ tc-expr^)
 (export check-subforms^)
diff --git a/collects/typed-scheme/private/def-binding.ss b/collects/typed-scheme/typecheck/def-binding.ss
similarity index 100%
rename from collects/typed-scheme/private/def-binding.ss
rename to collects/typed-scheme/typecheck/def-binding.ss
diff --git a/collects/typed-scheme/private/internal-forms.ss b/collects/typed-scheme/typecheck/internal-forms.ss
similarity index 100%
rename from collects/typed-scheme/private/internal-forms.ss
rename to collects/typed-scheme/typecheck/internal-forms.ss
diff --git a/collects/typed-scheme/private/provide-handling.ss b/collects/typed-scheme/typecheck/provide-handling.ss
similarity index 96%
rename from collects/typed-scheme/private/provide-handling.ss
rename to collects/typed-scheme/typecheck/provide-handling.ss
index 1d4f67bf..4ca36a34 100644
--- a/collects/typed-scheme/private/provide-handling.ss
+++ b/collects/typed-scheme/typecheck/provide-handling.ss
@@ -1,11 +1,12 @@
 #lang scheme/base
 
+(require (except-in "../utils/utils.ss" extend))
 (require (only-in srfi/1/list s:member)
          syntax/kerncase 
          mzlib/trace
-         "type-contract.ss"
-         "type-rep.ss"
-         "tc-utils.ss"
+         (private type-contract)
+         (rep type-rep)
+	 (utils tc-utils)
          "def-binding.ss")
 
 (require (for-template scheme/base
diff --git a/collects/typed-scheme/private/signatures.ss b/collects/typed-scheme/typecheck/signatures.ss
similarity index 51%
rename from collects/typed-scheme/private/signatures.ss
rename to collects/typed-scheme/typecheck/signatures.ss
index 9f8b0dba..b5ab6ebc 100644
--- a/collects/typed-scheme/private/signatures.ss
+++ b/collects/typed-scheme/typecheck/signatures.ss
@@ -2,41 +2,11 @@
 (require scheme/unit)
 (provide (all-defined-out))
 
-(define-signature dmap^
-  (dmap-meet))
-
-(define-signature promote-demote^
-  (var-promote var-demote))
-
-(define-signature constraints^
-  (exn:infer?
-   fail-sym
-   ;; inference failure - masked before it gets to the user program
-   (define-syntaxes (fail!)
-     (syntax-rules ()
-       [(_ s t) (raise fail-sym)]))
-   cset-meet cset-meet*
-   no-constraint
-   empty-cset
-   insert
-   cset-combine
-   c-meet))
-
-(define-signature restrict^
-  (restrict))
-
-(define-signature infer^
-  (infer infer/vararg infer/dots))
-
-
-
-;; cycle 2
-
 (define-signature typechecker^
   (type-check tc-toplevel-form))
 
 (define-signature tc-expr^
-  (tc-expr tc-expr/check tc-expr/check/t check-below tc-literal tc-exprs tc-exprs/check tc-expr/t #;check-expr))
+  (tc-expr tc-expr/check tc-expr/check/t check-below tc-exprs tc-exprs/check tc-expr/t))
 
 (define-signature check-subforms^
   (check-subforms/ignore check-subforms/with-handlers check-subforms/with-handlers/check))
diff --git a/collects/typed-scheme/private/tc-app-unit.ss b/collects/typed-scheme/typecheck/tc-app-unit.ss
similarity index 98%
rename from collects/typed-scheme/private/tc-app-unit.ss
rename to collects/typed-scheme/typecheck/tc-app-unit.ss
index 5d8afe8a..3c04db14 100644
--- a/collects/typed-scheme/private/tc-app-unit.ss
+++ b/collects/typed-scheme/typecheck/tc-app-unit.ss
@@ -1,19 +1,13 @@
 #lang scheme/unit
 
+(require (only-in "../utils/utils.ss" debug in-syntax printf/log in-pairs rep utils private env [infer r:infer]))
 (require "signatures.ss"
-         "type-rep.ss"
-         "effect-rep.ss"
-         "tc-utils.ss"
-         "subtype.ss"
-         "infer.ss"
-         (only-in "utils.ss" debug in-syntax printf/log in-pairs)
-         "union.ss"
-         "type-utils.ss"
-         "type-effect-convenience.ss"
-         "type-effect-printer.ss"
-         "type-annotation.ss"
-         "resolve-type.ss"
-         "type-environments.ss"
+         (rep type-rep effect-rep)
+	 (utils tc-utils)
+	 (private subtype type-utils union type-effect-convenience type-effect-printer resolve-type
+		  type-annotation)
+         (r:infer infer)
+	 (env type-environments)
          (only-in srfi/1 alist-delete)
          (only-in scheme/private/class-internal make-object do-make-object)
          mzlib/trace mzlib/pretty syntax/kerncase scheme/match
@@ -21,7 +15,7 @@
          (for-template 
           "internal-forms.ss" scheme/base 
           (only-in scheme/private/class-internal make-object do-make-object)))
-(require "constraint-structs.ss")
+(require (r:infer constraint-structs))
 
 (import tc-expr^ tc-lambda^ tc-dots^)
 (export tc-app^)
diff --git a/collects/typed-scheme/private/tc-expr-unit.ss b/collects/typed-scheme/typecheck/tc-expr-unit.ss
similarity index 96%
rename from collects/typed-scheme/private/tc-expr-unit.ss
rename to collects/typed-scheme/typecheck/tc-expr-unit.ss
index 163fa343..7e32c0c7 100644
--- a/collects/typed-scheme/private/tc-expr-unit.ss
+++ b/collects/typed-scheme/typecheck/tc-expr-unit.ss
@@ -1,21 +1,15 @@
 #lang scheme/unit
 
 
+(require (rename-in "../utils/utils.ss" [private r:private]))
 (require syntax/kerncase
          scheme/match
          "signatures.ss"
-         "type-utils.ss"
-         "utils.ss" ;; doesn't need tests
-         "type-rep.ss" ;; doesn't need tests
-         "type-effect-convenience.ss" ;; maybe needs tests
-         "union.ss"
-         "subtype.ss" ;; has tests
-         "parse-type.ss" ;; has tests
-         "tc-utils.ss" ;; doesn't need tests
-         "lexical-env.ss" ;; maybe needs tests
-         "type-annotation.ss" ;; has tests
-         "effect-rep.ss"
-         (only-in "type-environments.ss" lookup current-tvars extend-env)
+         (r:private type-utils type-effect-convenience union subtype parse-type type-annotation)
+         (rep type-rep effect-rep)
+         (utils tc-utils)
+         (env lexical-env)
+         (only-in (env type-environments) lookup current-tvars extend-env)
          scheme/private/class-internal
          (only-in srfi/1 split-at))
 
diff --git a/collects/typed-scheme/private/tc-lambda-unit.ss b/collects/typed-scheme/typecheck/tc-lambda-unit.ss
similarity index 96%
rename from collects/typed-scheme/private/tc-lambda-unit.ss
rename to collects/typed-scheme/typecheck/tc-lambda-unit.ss
index 455d6acd..962c480e 100644
--- a/collects/typed-scheme/private/tc-lambda-unit.ss
+++ b/collects/typed-scheme/typecheck/tc-lambda-unit.ss
@@ -1,20 +1,15 @@
 #lang scheme/unit
 
+(require (rename-in "../utils/utils.ss" [infer r:infer] [extend r:extend]))
 (require "signatures.ss"
          mzlib/trace
          scheme/list
-         (except-in "type-rep.ss" make-arr) ;; doesn't need tests
-         "type-effect-convenience.ss" ;; maybe needs tests
-         "type-environments.ss" ;; doesn't need tests
-         "lexical-env.ss" ;; maybe needs tests
-         "type-annotation.ss" ;; has tests
-         (except-in "utils.ss" extend)
-         "type-utils.ss"
-         "effect-rep.ss"
-         "tc-utils.ss"
-         "union.ss"
+         (except-in (rep type-rep effect-rep) make-arr) ;; doesn't need tests
+         (private type-effect-convenience type-annotation union type-utils)
+	 (env type-environments lexical-env)
+	 (utils tc-utils)
          mzlib/plt-match
-         (only-in "type-effect-convenience.ss" [make-arr* make-arr]))
+         (only-in (private type-effect-convenience) [make-arr* make-arr]))
 (require (for-template scheme/base "internal-forms.ss"))
 
 (import tc-expr^)
diff --git a/collects/typed-scheme/private/tc-let-unit.ss b/collects/typed-scheme/typecheck/tc-let-unit.ss
similarity index 96%
rename from collects/typed-scheme/private/tc-let-unit.ss
rename to collects/typed-scheme/typecheck/tc-let-unit.ss
index eb292852..9bf2bf3f 100644
--- a/collects/typed-scheme/private/tc-let-unit.ss
+++ b/collects/typed-scheme/typecheck/tc-let-unit.ss
@@ -1,14 +1,9 @@
 #lang scheme/unit
 
+(require (rename-in "../utils/utils.ss" [infer r:infer]))
 (require "signatures.ss"
-         "type-effect-convenience.ss"
-         "lexical-env.ss"
-         "type-annotation.ss"
-         "type-alias-env.ss"
-         "type-env.ss"
-         "parse-type.ss"
-         "utils.ss"
-         "type-utils.ss"
+         (private type-effect-convenience type-annotation parse-type type-utils)
+	 (env lexical-env type-alias-env type-env)
          syntax/free-vars
          mzlib/trace
          scheme/match
diff --git a/collects/typed-scheme/private/tc-structs.ss b/collects/typed-scheme/typecheck/tc-structs.ss
similarity index 95%
rename from collects/typed-scheme/private/tc-structs.ss
rename to collects/typed-scheme/typecheck/tc-structs.ss
index 23c8a430..86233c0d 100644
--- a/collects/typed-scheme/private/tc-structs.ss
+++ b/collects/typed-scheme/typecheck/tc-structs.ss
@@ -1,15 +1,12 @@
 #lang scheme/base
 
-(require "type-rep.ss" ;; doesn't need tests
-         "type-effect-convenience.ss" ;; maybe needs tests
-         "type-env.ss" ;; maybe needs tests
-         "type-utils.ss"
-         "parse-type.ss" ;; has tests
-         "type-environments.ss" ;; doesn't need tests
-         "type-name-env.ss" ;; maybe needs tests
-         "union.ss"
-         "tc-utils.ss"
-         "resolve-type.ss"
+(require (except-in "../utils/utils.ss" extend))
+(require (rep type-rep)
+	 (private type-effect-convenience
+		  type-utils parse-type
+		  union resolve-type)
+	 (env type-env type-environments type-name-env)
+	 (utils tc-utils)
          "def-binding.ss"
          syntax/kerncase
          syntax/struct
diff --git a/collects/typed-scheme/private/tc-toplevel.ss b/collects/typed-scheme/typecheck/tc-toplevel.ss
similarity index 94%
rename from collects/typed-scheme/private/tc-toplevel.ss
rename to collects/typed-scheme/typecheck/tc-toplevel.ss
index 23b3614c..5f2d36f2 100644
--- a/collects/typed-scheme/private/tc-toplevel.ss
+++ b/collects/typed-scheme/typecheck/tc-toplevel.ss
@@ -1,26 +1,17 @@
 #lang scheme/unit
 
 
+(require (rename-in "../utils/utils.ss" [infer r:infer]))
 (require syntax/kerncase
          mzlib/etc
          scheme/match
          "signatures.ss"
          "tc-structs.ss"
-         "type-utils.ss"
-         "utils.ss" ;; doesn't need tests
-         "type-effect-convenience.ss" ;; maybe needs tests
-         "internal-forms.ss" ;; doesn't need tests
-         "type-env.ss" ;; maybe needs tests
-         "parse-type.ss" ;; has tests
-         "tc-utils.ss" ;; doesn't need tests
-         "type-annotation.ss" ;; has tests
-         "type-name-env.ss" ;; maybe needs tests
-         "init-envs.ss"
-         "mutated-vars.ss"
+         (private type-utils type-effect-convenience parse-type type-annotation mutated-vars type-contract)
+	 (env type-env init-envs type-name-env type-alias-env)
+	 (utils tc-utils)
+	 "provide-handling.ss"
          "def-binding.ss"
-         "provide-handling.ss"
-         "type-alias-env.ss"
-         "type-contract.ss"
          (for-template
           "internal-forms.ss"
           mzlib/contract
diff --git a/collects/typed-scheme/private/typechecker.ss b/collects/typed-scheme/typecheck/typechecker.ss
similarity index 89%
rename from collects/typed-scheme/private/typechecker.ss
rename to collects/typed-scheme/typecheck/typechecker.ss
index 3ec16bcf..ed935ff9 100644
--- a/collects/typed-scheme/private/typechecker.ss
+++ b/collects/typed-scheme/typecheck/typechecker.ss
@@ -1,6 +1,7 @@
 #lang scheme/base
 
-(require "unit-utils.ss"
+(require "../utils/utils.ss")
+(require (utils unit-utils)
          mzlib/trace
          (only-in scheme/unit provide-signature-elements)
          "signatures.ss" "tc-toplevel.ss"         
diff --git a/collects/typed-scheme/typed-scheme.ss b/collects/typed-scheme/typed-scheme.ss
index 2eb33e21..0bcfc701 100644
--- a/collects/typed-scheme/typed-scheme.ss
+++ b/collects/typed-scheme/typed-scheme.ss
@@ -1,22 +1,18 @@
 #lang scheme/base
 
-(require "private/base-env.ss"
-         "private/base-types.ss"
+(require (rename-in "utils/utils.ss" [infer r:infer]))
+
+(require (private base-env base-types)
          (for-syntax 
           scheme/base
-          "private/type-utils.ss"
-          "private/typechecker.ss"
-          "private/type-rep.ss"
-          "private/provide-handling.ss"
-          "private/type-environments.ss" 
-          "private/tc-utils.ss"
-          "private/type-name-env.ss"
-          "private/type-alias-env.ss"
-          (except-in "private/utils.ss" extend)
-          (only-in "private/infer-dummy.ss" infer-param)
-          "private/infer.ss"
-          "private/type-effect-convenience.ss"
-          "private/type-contract.ss"
+	  (private type-utils type-contract type-effect-convenience)
+	  (typecheck typechecker provide-handling)
+	  (env type-environments type-name-env type-alias-env)
+	  (r:infer infer)
+	  (utils tc-utils)
+	  (rep type-rep)
+	  (except-in (utils utils) infer extend)
+          (only-in (r:infer infer-dummy) infer-param)
           scheme/nest
           syntax/kerncase
           scheme/match))
diff --git a/collects/typed-scheme/private/tc-utils.ss b/collects/typed-scheme/utils/tc-utils.ss
similarity index 100%
rename from collects/typed-scheme/private/tc-utils.ss
rename to collects/typed-scheme/utils/tc-utils.ss
diff --git a/collects/typed-scheme/private/utils.ss b/collects/typed-scheme/utils/utils.ss
similarity index 86%
rename from collects/typed-scheme/private/utils.ss
rename to collects/typed-scheme/utils/utils.ss
index 80c3f802..ad04ad79 100644
--- a/collects/typed-scheme/private/utils.ss
+++ b/collects/typed-scheme/utils/utils.ss
@@ -2,6 +2,7 @@
 
 (require (for-syntax scheme/base)
          mzlib/plt-match
+	 scheme/require-syntax
          mzlib/struct)
 
 (provide with-syntax* syntax-map start-timing do-time reverse-begin printf/log
@@ -16,7 +17,38 @@
          in-list-forever
          extend
          debug
-         in-syntax)
+         in-syntax
+	 ;; require macros
+	 rep utils typecheck infer env private)
+
+(define-syntax (define-requirer stx)
+  (syntax-case stx ()
+    [(_ nm)
+     #`(...
+	(define-require-syntax nm
+	  (lambda (stx)
+	    (syntax-case stx ()
+	      [(_ id ...)
+	       (andmap identifier? (syntax->list #'(id ...)))
+	       (with-syntax ([(id* ...) (map (lambda (id) (datum->syntax 
+							   id 
+							   (string->symbol
+							    (string-append 
+							     "typed-scheme/"
+							     #,(symbol->string (syntax-e #'nm))
+							     "/" 
+							     (symbol->string (syntax-e id))))
+							   id id))
+					     (syntax->list #'(id ...)))])
+			    (syntax/loc stx (combine-in id* ...)))]))))]))
+
+
+(define-requirer rep)
+(define-requirer infer)
+(define-requirer typecheck)
+(define-requirer utils)
+(define-requirer env)
+(define-requirer private)
 
 (define-sequence-syntax in-syntax 
   (lambda () #'syntax->list)