diff --git a/racket/typed/examples/require-struct/omit-accs/lib.rkt b/racket/typed/examples/require-struct/omit-accs/lib.rkt
new file mode 100644
index 0000000..5900a63
--- /dev/null
+++ b/racket/typed/examples/require-struct/omit-accs/lib.rkt
@@ -0,0 +1,12 @@
+#lang racket
+
+(struct egg (size day) #:transparent)
+
+(provide (except-out (struct-out egg)
+                     egg-size
+                     egg-day))
+
+
+(struct chicken (eggs) #:transparent)
+
+(provide chicken)
diff --git a/racket/typed/examples/require-struct/omit-accs/require-omit-accs.rkt b/racket/typed/examples/require-struct/omit-accs/require-omit-accs.rkt
new file mode 100644
index 0000000..399901c
--- /dev/null
+++ b/racket/typed/examples/require-struct/omit-accs/require-omit-accs.rkt
@@ -0,0 +1,18 @@
+#lang typed/syndicate/roles
+
+(require-struct egg #:as Egg #:from "lib.rkt" #:omit-accs)
+
+(define e (egg 5 "Sun"))
+
+(match e
+  [(egg $sz $d)
+   (displayln sz)
+   (displayln d)])
+
+(require-struct chicken #:as Chicken #:from "lib.rkt" #:omit-accs)
+
+(define c (chicken (list e e e)))
+
+(match c
+  [(chicken $eggs)
+   (displayln eggs)])
diff --git a/racket/typed/examples/require:typed/opaque/client-arity.rkt b/racket/typed/examples/require:typed/opaque/client-arity.rkt
new file mode 100644
index 0000000..abb0c26
--- /dev/null
+++ b/racket/typed/examples/require:typed/opaque/client-arity.rkt
@@ -0,0 +1,8 @@
+#lang typed/syndicate
+
+(require/typed "lib.rkt"
+  [#:opaque Vec #:arity = 3]
+  [ones : (Vec Int Int Int)]
+  [vec+ : (→fn (Vec Int Int Int) (Vec Int Int Int) (Vec Int Int Int))])
+
+(vec+ ones ones)
diff --git a/racket/typed/examples/require:typed/opaque/client.rkt b/racket/typed/examples/require:typed/opaque/client.rkt
new file mode 100644
index 0000000..2093882
--- /dev/null
+++ b/racket/typed/examples/require:typed/opaque/client.rkt
@@ -0,0 +1,8 @@
+#lang typed/syndicate
+
+(require/typed "lib.rkt"
+  [#:opaque Vec]
+  [ones : Vec]
+  [vec+ : (→fn Vec Vec Vec)])
+
+(vec+ ones ones)
diff --git a/racket/typed/examples/require:typed/opaque/lib.rkt b/racket/typed/examples/require:typed/opaque/lib.rkt
new file mode 100644
index 0000000..218f0ce
--- /dev/null
+++ b/racket/typed/examples/require:typed/opaque/lib.rkt
@@ -0,0 +1,13 @@
+#lang racket
+
+(provide ones
+         vec+)
+
+(struct vec (x y z) #:transparent)
+
+(define ones (vec 1 1 1))
+
+(define (vec+ v1 v2)
+  (vec (+ (vec-x v1) (vec-x v2))
+       (+ (vec-y v1) (vec-y v2))
+       (+ (vec-z v1) (vec-z v2))))
diff --git a/racket/typed/syndicate/core-types.rkt b/racket/typed/syndicate/core-types.rkt
index 0d97e7b..d492b51 100644
--- a/racket/typed/syndicate/core-types.rkt
+++ b/racket/typed/syndicate/core-types.rkt
@@ -730,7 +730,7 @@
 ;; TODO: this implementation shares a lot with that of define-constructor
 (define-syntax (require-struct stx)
   (syntax-parse stx
-    [(_ ucons:id #:as ty-cons:id #:from lib)
+    [(_ ucons:id #:as ty-cons:id #:from lib (~optional (~and omit-accs #:omit-accs)))
      (with-syntax* ([TypeCons #'ty-cons]
                     [MakeTypeCons (format-id #'TypeCons "make-~a" #'TypeCons)]
                     [GetTypeParams (format-id #'TypeCons "get-~a-type-params" #'TypeCons)]
@@ -751,7 +751,6 @@
                (raise-syntax-error #f "number of slots must be exact" #'#,stx #'ucons))
              (unless (boolean? sup)
                (raise-syntax-error #f "structs with super-type not supported" #'#,stx #'ucons))
-             (define accs (cleanup-accs #'ucons accs/rev))
              (define arity (length accs/rev))
              )
            (define-for-syntax (TypeConsExtraInfo stx)
@@ -767,10 +766,14 @@
            (define-syntax GetTypeParams (mk-type-params-fetcher #'TypeCons))
            (define-syntax Cons- (mk-constructor-type-rule arity #'orig-struct-info #'TypeCons))
            (define-syntax ucons
-             (user-ctor #'Cons- #'orig-struct-info 'type-tag #'TypeCons (cleanup-accs #'ucons accs/rev) #;accs))
-           (define-syntax mk-struct-accs
-             (define-struct-accs accs/rev #'TypeCons #'lib))
-           (mk-struct-accs ucons))))]))
+             (user-ctor #'Cons- #'orig-struct-info 'type-tag #'TypeCons (cleanup-accs #'ucons accs/rev)))
+           #,(unless (attribute omit-accs)
+               (quasisyntax/loc stx
+                 (begin-
+                   (define-syntax mk-struct-accs
+                     (define-struct-accs accs/rev #'TypeCons #'lib))
+                   (mk-struct-accs ucons))))
+           )))]))
 
 (begin-for-syntax
   (define-syntax ~constructor-extra-info
@@ -838,21 +841,32 @@
 ;; Require & Provide
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(begin-for-syntax
+  (define-syntax-class opaque-require-clause
+    #:datum-literals (= > >=)
+    #:attributes (type-definition)
+    (pattern [#:opaque ty-name:id]
+             #:attr type-definition #'(define-base-type ty-name))
+    (pattern [#:opaque ty-name:id #:arity (~and op (~or* = > >=)) arity:nat]
+             #:attr type-definition #'(define-product-type ty-name #:arity op arity))))
+
 ;; Import and ascribe a type from an untyped module
 ;; TODO: this is where contracts would need to go
 (define-syntax (require/typed stx)
   (syntax-parse stx
     #:datum-literals (:)
-    [(_ lib [name:id : ty:type] ...)
+    [(_ lib
+        (~alt [name:id : ty]
+              opaque-clause:opaque-require-clause)
+        ...)
      #:with (name- ...) (format-ids "~a-" #'(name ...))
-     #:with (serialized-ty ...) (for/list ([t (in-syntax #'(ty.norm ...))])
-                                  (serialize-syntax t))
      (syntax/loc stx
        (begin-
+         opaque-clause.type-definition ...
          (require (only-in lib [name name-] ...))
          (define-syntax name
            (make-variable-like-transformer
-            (add-orig (assign-type #'name- (deserialize-syntax #'serialized-ty)
+            (add-orig (assign-type #'name- (deserialize-syntax (serialize-syntax (type-eval #'ty)))
                                    #:wrap? #f) #'name)))
          ...))]))