diff --git a/xenomorph/xenomorph/array.rkt b/xenomorph/xenomorph/array.rkt
index 2d8ec25b..72f64fac 100644
--- a/xenomorph/xenomorph/array.rkt
+++ b/xenomorph/xenomorph/array.rkt
@@ -23,7 +23,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Array.coffee
     (unless (boolean? @count-bytes?)
       (raise-argument-error 'x:array "boolean" @count-bytes?))
 
-    (define/augride (x:decode port parent)
+    (define/augride (:decode port parent)
       (define new-parent (if (x:int? @len)
                              (mhasheq x:parent-key parent
                                       x:start-offset-key (pos port)
@@ -43,12 +43,12 @@ https://github.com/mbutterick/restructure/blob/master/src/Array.coffee
                            [else +inf.0]))
          (for/list ([i (in-naturals)]
                     #:break (or (eof-object? (peek-byte port)) (= (pos port) end-pos)))
-           (send @type x:decode port new-parent))]
+           (send @type :decode port new-parent))]
         ;; we have len, which is treated as count of items
         [else (for/list ([i (in-range len)])
-                (send @type x:decode port new-parent))]))
+                (send @type :decode port new-parent))]))
 
-    (define/augride (x:encode array port [parent #f])
+    (define/augride (:encode array port [parent #f])
       (unless (sequence? array)
         (raise-argument-error 'xarray-encode "sequence" array))
       (define (encode-items parent)
@@ -58,32 +58,32 @@ https://github.com/mbutterick/restructure/blob/master/src/Array.coffee
                #;[item-count (length items)]
                #;[max-items (if (number? (xarray-len xa)) (xarray-len xa) item-count)])
           (for ([item array])
-            (send @type x:encode item port parent))))
+            (send @type :encode item port parent))))
       (cond
         [(x:int? @len)
          (define new-parent (mhasheq x:pointers-key null
                                      x:start-offset-key (pos port)
                                      x:parent-key parent))
-         (hash-set! new-parent x:pointer-offset-key (+ (pos port) (x:size array new-parent)))
-         (send @len x:encode (length array) port) ; encode length at front
+         (hash-set! new-parent x:pointer-offset-key (+ (pos port) (:size array new-parent)))
+         (send @len :encode (length array) port) ; encode length at front
          (encode-items new-parent)
          (for ([ptr (in-list (hash-ref new-parent x:pointers-key))]) ; encode pointer data at end
-           (send (x:ptr-type ptr) x:encode (x:ptr-val ptr) port))]
+           (send (x:ptr-type ptr) :encode (x:ptr-val ptr) port))]
         [else (encode-items parent)]))
 
-    (define/augride (x:size [val #f] [parent #f])
+    (define/augride (:size [val #f] [parent #f])
       (when val (unless (sequence? val)
                   (raise-argument-error 'xarray-size "sequence" val)))
       (cond
         [val (define-values (new-parent len-size)
                (if (x:int? @len)
-                   (values (mhasheq x:parent-key parent) (send @len x:size))
+                   (values (mhasheq x:parent-key parent) (send @len :size))
                    (values parent 0)))
              (define items-size (for/sum ([item val])
-                                  (send @type x:size item new-parent)))
+                                  (send @type :size item new-parent)))
              (+ items-size len-size)]
         [else (define count (resolve-length @len #f parent))
-              (define size (send @type x:size #f parent))
+              (define size (send @type :size #f parent))
               (* size count)]))))
 
 (define (x:array [type-arg #f] [len-arg #f] [length-type-arg 'count]
diff --git a/xenomorph/xenomorph/base.rkt b/xenomorph/xenomorph/base.rkt
index 2637089d..632d57bd 100644
--- a/xenomorph/xenomorph/base.rkt
+++ b/xenomorph/xenomorph/base.rkt
@@ -39,11 +39,11 @@
 (define (encode xo val [port-arg (current-output-port)]
                 #:parent [parent #f])
   (define port (if (output-port? port-arg) port-arg (open-output-bytes)))
-  (send xo x:encode val port parent)
+  (send xo :encode val port parent)
   (unless port-arg (get-output-bytes port)))
                                       
 (define (size xo [val #f] #:parent [parent #f])
-  (send xo x:size val parent))
+  (send xo :size val parent))
 
 (define (xenomorphic-type? x) (is-a? x xenobase%))
 (define xenomorphic? xenomorphic-type?)
@@ -69,18 +69,18 @@
   (class object%
     (super-new)
     
-    (define/pubment (x:decode input-port [parent #f])
-      (post-decode (inner (error 'x:decode-not-augmented) x:decode input-port parent)))
+    (define/pubment (:decode input-port [parent #f])
+      (post-decode (inner (error ':decode-not-augmented) :decode input-port parent)))
 
     (define/public (decode input-port [parent #f])
-      (x:decode input-port parent))
+      (:decode input-port parent))
     
-    (define/pubment (x:encode val output-port [parent #f])
-      (define encode-result (inner (error 'x:encode-not-augmented) x:encode (pre-encode val) output-port parent))
+    (define/pubment (:encode val output-port [parent #f])
+      (define encode-result (inner (error ':encode-not-augmented) :encode (pre-encode val) output-port parent))
       (when (bytes? encode-result) (write-bytes encode-result output-port)))
     
-    (define/pubment (x:size [val #f] [parent #f] . args)
-      (define size (inner 0 x:size val parent . args))
+    (define/pubment (:size [val #f] [parent #f] . args)
+      (define size (inner 0 :size val parent . args))
       (unless (and (integer? size) (not (negative? size)))
         (raise-argument-error 'size "nonnegative integer" size))
       size)
diff --git a/xenomorph/xenomorph/bitfield.rkt b/xenomorph/xenomorph/bitfield.rkt
index 5cdaf169..d71d5287 100644
--- a/xenomorph/xenomorph/bitfield.rkt
+++ b/xenomorph/xenomorph/bitfield.rkt
@@ -14,22 +14,22 @@ https://github.com/mbutterick/restructure/blob/master/src/Bitfield.coffee
     (unless (andmap (λ (f) (or (symbol? f) (not f))) @flags)
       (raise-argument-error '+xbitfield "list of symbols" @flags))
 
-    (define/augment (x:decode port parent)
-      (define val (send @type x:decode port))
+    (define/augment (:decode port parent)
+      (define val (send @type :decode port))
       (define flag-hash (mhasheq))
       (for ([(flag idx) (in-indexed @flags)]
             #:when flag)
         (hash-set! flag-hash flag (bitwise-bit-set? val idx)))
       flag-hash)
 
-    (define/augment (x:encode flag-hash port [parent #f])
+    (define/augment (:encode flag-hash port [parent #f])
       (define bit-int (for/sum ([(flag idx) (in-indexed @flags)]
                                 #:when (and flag (hash-ref flag-hash flag #f)))
                         (arithmetic-shift 1 idx)))
-      (send @type x:encode bit-int port))
+      (send @type :encode bit-int port))
     
-    (define/augment (x:size [val #f] [parent #f])
-      (send @type x:size))))
+    (define/augment (:size [val #f] [parent #f])
+      (send @type :size))))
   
 (define (x:bitfield [type-arg #f] [flag-arg #f]
                     #:type [type-kwarg #f]
diff --git a/xenomorph/xenomorph/buffer.rkt b/xenomorph/xenomorph/buffer.rkt
index 20885024..ea3651ea 100644
--- a/xenomorph/xenomorph/buffer.rkt
+++ b/xenomorph/xenomorph/buffer.rkt
@@ -14,17 +14,17 @@ https://github.com/mbutterick/restructure/blob/master/src/Buffer.coffee
     (unless (length-resolvable? @len)
       (raise-argument-error 'x:buffer "resolvable length" @len))
 
-    (define/augment (x:decode port parent)
+    (define/augment (:decode port parent)
       (read-bytes (resolve-length @len port parent)))
 
-    (define/augment (x:encode buf port [parent #f])
+    (define/augment (:encode buf port [parent #f])
       (unless (bytes? buf)
         (raise-argument-error 'x:buffer-encode "bytes" buf))
       (when (x:int? @len)
-        (send @len x:encode (bytes-length buf) port))
+        (send @len :encode (bytes-length buf) port))
       (write-bytes buf port))
     
-    (define/augment (x:size [val #f] [parent #f])
+    (define/augment (:size [val #f] [parent #f])
       (match val
         [(? bytes?) (bytes-length val)]
         [(== #false) (resolve-length @len val parent)]
diff --git a/xenomorph/xenomorph/enum.rkt b/xenomorph/xenomorph/enum.rkt
index beeb79e5..ba497fe4 100644
--- a/xenomorph/xenomorph/enum.rkt
+++ b/xenomorph/xenomorph/enum.rkt
@@ -17,17 +17,17 @@ https://github.com/mbutterick/restructure/blob/master/src/Enum.coffee
     (unless (list? @values)
       (raise-argument-error 'x:enum "list of values" @values))
 
-    (define/augment (x:decode port parent)
-      (define index (send @type x:decode port parent))
+    (define/augment (:decode port parent)
+      (define index (send @type :decode port parent))
       (or (list-ref @values index) index))
 
-    (define/augment (x:encode val port [parent #f])
+    (define/augment (:encode val port [parent #f])
       (match (index-of @values val)
-        [(? values idx) (send @type x:encode idx port parent)]
+        [(? values idx) (send @type :encode idx port parent)]
         [_ (raise-argument-error 'x:enum-encode "valid option" val)]))
     
-    (define/augment (x:size [val #f] [parent #f])
-      (send @type x:size val parent))))
+    (define/augment (:size [val #f] [parent #f])
+      (send @type :size val parent))))
 
 (define (x:enum [type-arg #f] [values-arg #f]
                 #:type [type-kwarg #f]
diff --git a/xenomorph/xenomorph/lazy-array.rkt b/xenomorph/xenomorph/lazy-array.rkt
index 63c49371..d412ea85 100644
--- a/xenomorph/xenomorph/lazy-array.rkt
+++ b/xenomorph/xenomorph/lazy-array.rkt
@@ -13,7 +13,7 @@ https://github.com/mbutterick/restructure/blob/master/src/LazyArray.coffee
     (super-new)
     (inherit-field [@type type] [@len len])
 
-    (define/override (x:decode port parent)
+    (define/override (:decode port parent)
       (define starting-pos (pos port)) ; ! placement matters. `resolve-length` will change `pos`
       (define len (resolve-length @len port parent))
       (define new-parent (if (x:int? @len)
@@ -26,17 +26,17 @@ https://github.com/mbutterick/restructure/blob/master/src/LazyArray.coffee
       (begin0
         (for/stream ([index (in-range len)])
           (define orig-pos (pos port))
-          (pos port (+ stream-starting-pos (* (send @type x:size #f new-parent) index)))
+          (pos port (+ stream-starting-pos (* (send @type :size #f new-parent) index)))
           (begin0
             (send @type decode port new-parent)
             (pos port orig-pos)))
-        (pos port (+ (pos port) (* len (send @type x:size #f new-parent))))))
+        (pos port (+ (pos port) (* len (send @type :size #f new-parent))))))
 
-    (define/override (x:encode val port [parent #f])
-      (super x:encode (if (stream? val) (stream->list val) val) port parent))
+    (define/override (:encode val port [parent #f])
+      (super :encode (if (stream? val) (stream->list val) val) port parent))
     
-    (define/override (x:size [val #f] [parent #f])
-      (super x:size (if (stream? val) (stream->list val) val) parent))))
+    (define/override (:size [val #f] [parent #f])
+      (super :size (if (stream? val) (stream->list val) val) parent))))
 
 (define (x:lazy-array [type-arg #f] [len-arg #f]
                       #:type [type-kwarg #f]
diff --git a/xenomorph/xenomorph/number.rkt b/xenomorph/xenomorph/number.rkt
index 33a676ab..ddf2a79c 100644
--- a/xenomorph/xenomorph/number.rkt
+++ b/xenomorph/xenomorph/number.rkt
@@ -35,7 +35,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Number.coffee
     
     (field [@bits (* @size 8)])
     
-    (define/augment (x:size . _) @size)))
+    (define/augment (:size . _) @size)))
 
 (define (x:int? x) (is-a? x x:int%))
 
@@ -53,14 +53,14 @@ https://github.com/mbutterick/restructure/blob/master/src/Number.coffee
     (field [bound-min (- signed-min delta)]
            [bound-max (- signed-max delta)])
                 
-    (define/augment (x:decode port . _)
+    (define/augment (:decode port . _)
       (define bs ((if (eq? @endian system-endian) values reverse-bytes) (read-bytes @size port)))
       (define uint (for/sum ([b (in-bytes bs)]
                              [i (in-naturals)])
                      (arithmetic-shift b (* 8 i))))
       (if signed (unsigned->signed uint @bits) uint))
                 
-    (define/augment (x:encode val . _)
+    (define/augment (:encode val . _)
       (unless (<= bound-min val bound-max)
         (raise-argument-error 'encode
                               (format "value that fits within ~a ~a-byte int (~a to ~a)" (if signed "signed" "unsigned") @size bound-min bound-max) val))
@@ -150,10 +150,10 @@ https://github.com/mbutterick/restructure/blob/master/src/Number.coffee
     (super-new)
     (inherit-field (@size size) (@endian endian))
                 
-    (define/augment (x:decode port . _)
+    (define/augment (:decode port . _)
       (floating-point-bytes->real (read-bytes @size port) (eq? @endian 'be)))
                 
-    (define/augment (x:encode val . _)
+    (define/augment (:encode val . _)
       (real->floating-point-bytes val @size (eq? @endian 'be)))))
 
 (define (x:float [size 4] #:endian [endian system-endian]
diff --git a/xenomorph/xenomorph/optional.rkt b/xenomorph/xenomorph/optional.rkt
index de9a35d4..9168cb5e 100644
--- a/xenomorph/xenomorph/optional.rkt
+++ b/xenomorph/xenomorph/optional.rkt
@@ -20,16 +20,16 @@ https://github.com/mbutterick/restructure/blob/master/src/Optional.coffee
         [(? procedure? proc) (proc parent)]
         [val val]))
 
-    (define/augment (x:decode port parent)
+    (define/augment (:decode port parent)
       (when (resolve-condition parent)
-        (send @type x:decode port parent)))
+        (send @type :decode port parent)))
 
-    (define/augment (x:encode val port [parent #f])
+    (define/augment (:encode val port [parent #f])
       (when (resolve-condition parent)
-        (send @type x:encode val port parent)))
+        (send @type :encode val port parent)))
     
-    (define/augment (x:size [val #f] [parent #f])
-      (if (resolve-condition parent) (send @type x:size val parent) 0))))
+    (define/augment (:size [val #f] [parent #f])
+      (if (resolve-condition parent) (send @type :size val parent) 0))))
 
 (define no-val (gensym))
 (define (x:optional [type-arg #f] [cond-arg no-val]
diff --git a/xenomorph/xenomorph/pointer.rkt b/xenomorph/xenomorph/pointer.rkt
index 9c27f8cb..f6335085 100644
--- a/xenomorph/xenomorph/pointer.rkt
+++ b/xenomorph/xenomorph/pointer.rkt
@@ -33,14 +33,14 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
                 [(@null-value null-value)]
                 [(@pointer-lazy? pointer-lazy?)])
 
-    (define/augment (x:decode port parent)
-      (define offset (send @offset-type x:decode port parent))
+    (define/augment (:decode port parent)
+      (define offset (send @offset-type :decode port parent))
       (cond
         [(and @allow-null? (= offset @null-value)) #false] ; handle null pointers
         [else
          (define relative (+ (case @pointer-relative-to
                                [(local) (hash-ref parent x:start-offset-key)]
-                               [(immediate) (- (pos port) (send @offset-type x:size))]
+                               [(immediate) (- (pos port) (send @offset-type :size))]
                                [(parent) (hash-ref (hash-ref parent x:parent-key) x:start-offset-key)]
                                [(global) (or (hash-ref (find-top-parent parent) x:start-offset-key) 0)]
                                [else (error 'unknown-pointer-style)])))
@@ -50,12 +50,12 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
                     (define orig-pos (pos port))
                     (pos port ptr)
                     (begin0
-                      (send @type x:decode port parent)
+                      (send @type :decode port parent)
                       (pos port orig-pos)))
                   (if @pointer-lazy? (delay (decode-value)) (decode-value))]
            [else ptr])]))
 
-    (define/augment (x:encode val-in port [parent #f])
+    (define/augment (:encode val-in port [parent #f])
       (unless parent ; todo: furnish default pointer context? adapt from Struct?
         (raise-argument-error 'xpointer-encode "valid pointer context" parent))
       (cond
@@ -67,17 +67,17 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
                               [else (error 'unknown-pointer-style)]))
          (define relative (+ (case @pointer-relative-to
                                [(local parent) (hash-ref new-parent x:start-offset-key)]
-                               [(immediate) (+ (pos port) (send @offset-type x:size val-in parent))]
+                               [(immediate) (+ (pos port) (send @offset-type :size val-in parent))]
                                [(global) 0])))
-         (send @offset-type x:encode (- (hash-ref new-parent x:pointer-offset-key) relative) port)
+         (send @offset-type :encode (- (hash-ref new-parent x:pointer-offset-key) relative) port)
          (define-values (type val) (resolve-pointer @type val-in))
          (hash-update! new-parent x:pointers-key
                        (λ (ptrs) (append ptrs (list (x:ptr type val parent)))))
          (hash-set! new-parent x:pointer-offset-key
-                    (+ (hash-ref new-parent x:pointer-offset-key) (send type x:size val parent)))]
-        [else (send @offset-type x:encode @null-value port)]))
+                    (+ (hash-ref new-parent x:pointer-offset-key) (send type :size val parent)))]
+        [else (send @offset-type :encode @null-value port)]))
 
-    (define/augment (x:size [val-in #f] [parent #f])
+    (define/augment (:size [val-in #f] [parent #f])
       (define new-parent (case @pointer-relative-to
                            [(local immediate) parent]
                            [(parent) (hash-ref parent x:parent-key)]
@@ -87,8 +87,8 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
       (when (and val new-parent)
         (hash-set! new-parent x:pointer-size-key
                    (and (hash-ref new-parent x:pointer-size-key #f)
-                        (+ (hash-ref new-parent x:pointer-size-key) (send type x:size val new-parent)))))
-      (send @offset-type x:size))))
+                        (+ (hash-ref new-parent x:pointer-size-key) (send type :size val new-parent)))))
+      (send @offset-type :size))))
 
 (define (x:pointer [offset-arg #f] [type-arg #f]
                    #:offset-type [offset-kwarg #f]
diff --git a/xenomorph/xenomorph/reserved.rkt b/xenomorph/xenomorph/reserved.rkt
index 3dbf44c8..650e91f2 100644
--- a/xenomorph/xenomorph/reserved.rkt
+++ b/xenomorph/xenomorph/reserved.rkt
@@ -15,15 +15,15 @@ https://github.com/mbutterick/restructure/blob/master/src/Reserved.coffee
     (unless (xenomorphic-type? @type)
       (raise-argument-error '+xoptional "xenomorphic type" @type))
 
-    (define/augment (x:decode port parent)
-      (pos port (+ (pos port) (x:size #f parent)))
+    (define/augment (:decode port parent)
+      (pos port (+ (pos port) (:size #f parent)))
       (void))
 
-    (define/augment (x:encode val port [parent #f])
-      (make-bytes (x:size val parent) 0))
+    (define/augment (:encode val port [parent #f])
+      (make-bytes (:size val parent) 0))
     
-    (define/augment (x:size [val #f] [parent #f])
-      (* (send @type x:size) (resolve-length @count #f parent)))))
+    (define/augment (:size [val #f] [parent #f])
+      (* (send @type :size) (resolve-length @count #f parent)))))
 
 (define (x:reserved [type-arg #f] [count-arg #f]
                     #:type [type-kwarg #f]
diff --git a/xenomorph/xenomorph/string.rkt b/xenomorph/xenomorph/string.rkt
index 3a5f5983..9f618d9f 100644
--- a/xenomorph/xenomorph/string.rkt
+++ b/xenomorph/xenomorph/string.rkt
@@ -38,7 +38,7 @@ https://github.com/mbutterick/restructure/blob/master/src/String.coffee
     (unless (or (procedure? @encoding) (memq @encoding supported-encodings))
       (raise-argument-error 'xstring (format "procedure or member of ~v" supported-encodings) @encoding))
 
-    (define/augment (x:decode port parent)
+    (define/augment (:decode port parent)
       (define len (or (resolve-length @len port parent) (count-nonzero-chars port)))
       (define encoding (match @encoding
                          [(? procedure? proc) (or (proc parent) 'ascii)]
@@ -48,7 +48,7 @@ https://github.com/mbutterick/restructure/blob/master/src/String.coffee
         (decode-string len port encoding)
         (pos port (+ (pos port) adjustment))))
 
-    (define/augment (x:encode val-arg port [parent #f])
+    (define/augment (:encode val-arg port [parent #f])
       (define val (if (string? val-arg) val-arg (format "~a" val-arg)))
       (define encoding (match @encoding
                          [(? procedure?) (@encoding (and parent (hash-ref parent val)) 'ascii)]
@@ -58,11 +58,11 @@ https://github.com/mbutterick/restructure/blob/master/src/String.coffee
       (when (and (exact-nonnegative-integer? @len) (> encoded-length @len))
         (raise-argument-error 'xstring-encode (format "string no longer than ~a" @len) val)) 
       (when (x:int? @len)
-        (send @len x:encode encoded-length port parent))
+        (send @len :encode encoded-length port parent))
       (define string-terminator (if @len (bytes) (bytes 0))) ; null terminated when no len
       (bytes-append encoded-str string-terminator)) 
     
-    (define/augment (x:size [val-arg #f] [parent #f])
+    (define/augment (:size [val-arg #f] [parent #f])
       (define val (cond
                     [(string? val-arg) val-arg]
                     [(not val-arg) #false]
@@ -74,7 +74,7 @@ https://github.com/mbutterick/restructure/blob/master/src/String.coffee
              (define string-size (bytes-length (encode-string val encoding)))
              (define strlen-size (cond
                                    [(not @len) 1]
-                                   [(x:int? @len) (send @len x:size)]
+                                   [(x:int? @len) (send @len :size)]
                                    [else 0]))
              (+ string-size strlen-size)]
         [else (resolve-length @len #f parent)]))))
diff --git a/xenomorph/xenomorph/struct.rkt b/xenomorph/xenomorph/struct.rkt
index 18a97aca..798c1567 100644
--- a/xenomorph/xenomorph/struct.rkt
+++ b/xenomorph/xenomorph/struct.rkt
@@ -30,7 +30,7 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
   (for ([(key type) (in-dict fields)])
     (define val (match type
                   [(? procedure? proc) (proc mheq)]
-                  [_ (send type x:decode port mheq)]))
+                  [_ (send type :decode port mheq)]))
     (unless (void? val)
       (hash-set! mheq key val))
     (hash-set! mheq x:current-offset-key (- (pos port) (hash-ref mheq x:start-offset-key))))
@@ -51,14 +51,14 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
     (when @fields (unless (dict? @fields)
                     (raise-argument-error '+xstruct "dict" @fields)))
 
-    (define/augride (x:decode port parent [len 0])
+    (define/augride (:decode port parent [len 0])
       (define res (setup-private-fields port parent len))
       (parse-fields port res @fields))
 
     (define/override (decode port parent)
-      (dict->mutable-hash (x:decode port parent)))
+      (dict->mutable-hash (:decode port parent)))
 
-    (define/augride (x:encode field-data port [parent-arg #f])
+    (define/augride (:encode field-data port [parent-arg #f])
       (unless (dict? field-data)
         (raise-result-error 'x:struct-encode "dict" field-data))
       ;; check keys, because `size` also relies on keys being valid
@@ -71,20 +71,20 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
                               x:parent-key parent-arg
                               x:val-key field-data
                               x:pointer-size-key 0)) 
-      (hash-set! parent x:pointer-offset-key (+ (pos port) (x:size field-data parent #f))) 
+      (hash-set! parent x:pointer-offset-key (+ (pos port) (:size field-data parent #f))) 
       (for ([(key type) (in-dict @fields)])
-        (send type x:encode (dict-ref field-data key) port parent))
+        (send type :encode (dict-ref field-data key) port parent))
       (for ([ptr (in-list (hash-ref parent x:pointers-key))])
         (match ptr
-          [(x:ptr type val parent) (send type x:encode val port parent)])))
+          [(x:ptr type val parent) (send type :encode val port parent)])))
     
-    (define/augride (x:size [val #f] [parent-arg #f] [include-pointers #t])
+    (define/augride (:size [val #f] [parent-arg #f] [include-pointers #t])
       (define parent (mhasheq x:parent-key parent-arg
                               x:val-key val
                               x:pointer-size-key 0))
       (define fields-size (for/sum ([(key type) (in-dict @fields)]
                                     #:when (xenomorphic-type? type))
-                            (send type x:size (and val (dict-ref val key)) parent)))
+                            (send type :size (and val (dict-ref val key)) parent)))
       (define pointers-size (if include-pointers (dict-ref parent x:pointer-size-key) 0))
       (+ fields-size pointers-size))))
 
diff --git a/xenomorph/xenomorph/versioned-struct.rkt b/xenomorph/xenomorph/versioned-struct.rkt
index fba35229..c7329675 100644
--- a/xenomorph/xenomorph/versioned-struct.rkt
+++ b/xenomorph/xenomorph/versioned-struct.rkt
@@ -31,7 +31,7 @@ https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
             (raise-argument-error 'x:versioned-struct-encode (format "valid field version: ~v" (dict-keys @versions)) version-key)))
       (if (x:struct? field-object) (get-field fields field-object) field-object))
 
-    (define/override (x:decode port parent [length 0])
+    (define/override (:decode port parent [length 0])
       (define res (setup-private-fields port parent length))
       (define which-version (match @type
                               [(? integer? int) int]
@@ -39,7 +39,7 @@ https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
                               [(? procedure? proc) #:when parent (proc parent)]
                               [(or (? symbol?) (? procedure?))
                                (raise-argument-error 'x:versioned-struct-decode "valid parent" parent)]
-                              [_ (send @type x:decode port parent)]))
+                              [_ (send @type :decode port parent)]))
       (dict-set! res x:version-key which-version)
 
       (cond
@@ -53,10 +53,10 @@ https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
            (raise-argument-error 'x:versioned-struct-decode (format "valid field version: ~v" (dict-keys @versions)) which-version)]))
       
       (match field-object
-        [(? x:versioned-struct?) (send field-object x:decode port parent)]
+        [(? x:versioned-struct?) (send field-object :decode port parent)]
         [_ (parse-fields port res field-object)]))
 
-    (define/override (x:encode field-data port [parent-arg #f])
+    (define/override (:encode field-data port [parent-arg #f])
       (unless (dict? field-data)
         (raise-argument-error 'x:versioned-struct-encode "dict" field-data))
       (define parent (mhasheq x:pointers-key null
@@ -64,22 +64,22 @@ https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
                               x:parent-key parent-arg
                               x:val-key field-data
                               x:pointer-size-key 0))
-      (hash-set! parent x:pointer-offset-key (+ (pos port) (x:size field-data parent #f)))
+      (hash-set! parent x:pointer-offset-key (+ (pos port) (:size field-data parent #f)))
       (unless (or (symbol? @type) (procedure? @type))
-        (send @type x:encode (dict-ref field-data x:version-key #f) port parent))
+        (send @type :encode (dict-ref field-data x:version-key #f) port parent))
       (for ([(key type) (in-dict (dict-ref @versions 'header null))])
-        (send type x:encode (dict-ref field-data key) port parent))
+        (send type :encode (dict-ref field-data key) port parent))
 
       (define fields (select-field-set field-data))
       (unless (andmap (λ (key) (member key (hash-keys field-data))) (dict-keys fields))
         (raise-argument-error 'x:versioned-struct-encode (format "hash that contains superset of xversioned-struct keys: ~a" (dict-keys fields)) (hash-keys field-data)))
       (for ([(key type) (in-dict fields)])
-        (send type x:encode (hash-ref field-data key) port parent))
+        (send type :encode (hash-ref field-data key) port parent))
       (for ([ptr (in-list (hash-ref parent x:pointers-key))])
         (match ptr
-          [(x:ptr type val parent) (send type x:encode val port parent)])))
+          [(x:ptr type val parent) (send type :encode val port parent)])))
     
-    (define/override (x:size [val #f] [parent-arg #f] [include-pointers #t])
+    (define/override (:size [val #f] [parent-arg #f] [include-pointers #t])
       (unless val
         (raise-argument-error 'x:versioned-struct-size "value" val))
       (define parent (mhasheq x:parent-key parent-arg
@@ -88,14 +88,14 @@ https://github.com/mbutterick/restructure/blob/master/src/VersionedStruct.coffee
       (define version-size
         (match @type
           [(or (? symbol?) (? procedure?)) 0]
-          [_ (send @type x:size (dict-ref val x:version-key) parent)]))
+          [_ (send @type :size (dict-ref val x:version-key) parent)]))
       
       (define header-size
         (for/sum ([(key type) (in-dict (dict-ref @versions 'header null))])
-          (send type x:size (and val (dict-ref val key)) parent)))
+          (send type :size (and val (dict-ref val key)) parent)))
       (define fields-size
         (for/sum ([(key type) (in-dict (select-field-set val))])
-          (send type x:size (and val (dict-ref val key)) parent)))
+          (send type :size (and val (dict-ref val key)) parent)))
       (define pointer-size (if include-pointers (dict-ref parent x:pointer-size-key) 0))
       (+ version-size header-size fields-size pointer-size))))