diff --git a/src/as2.lisp b/src/as2.lisp
index 07cef7a..79f2d40 100644
--- a/src/as2.lisp
+++ b/src/as2.lisp
@@ -131,34 +131,35 @@
 
 ;;; From Object to JSON
 
-(defun kebab-camel (kebab-string)
-  "Convert KEBAB-STRING as kebab-case to camelCase."
-  (with-output-to-string (out)
-    (loop :with capitalize = nil
-          :for char :across kebab-string
-          :do (cond ((char= char #\-)
-                     (setf capitalize t))
-                    (capitalize
-                     (write-char (char-upcase char) out)
-                     (setf capitalize nil))
-                    (t (write-char (char-downcase char) out))))))
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (defun kebab-camel (kebab-string)
+    "Convert KEBAB-STRING as kebab-case to camelCase."
+    (with-output-to-string (out)
+      (loop :with capitalize = nil
+            :for char :across kebab-string
+            :do (cond ((char= char #\-)
+                       (setf capitalize t))
+                      (capitalize
+                       (write-char (char-upcase char) out)
+                       (setf capitalize nil))
+                      (t (write-char (char-downcase char) out))))))
 
-(defun remove-postfix (postfix string)
-  "Remove the given postfix from the string if it exists."
-  (let* ((postfix-length (length postfix))
-         (string-length (length string))
-         (index (- string-length postfix-length)))
-    (if (and (>= string-length postfix-length)
-             (string= postfix (subseq string index)))
-        (subseq string 0 index)
-        string)))
+  (defun remove-postfix (postfix string)
+    "Remove the given postfix from the string if it exists."
+    (let* ((postfix-length (length postfix))
+           (string-length (length string))
+           (index (- string-length postfix-length)))
+      (if (and (>= string-length postfix-length)
+               (string= postfix (subseq string index)))
+          (subseq string 0 index)
+          string)))
 
-(defun remove-as2-postfix (string)
-  "Remove the '-as2' prefix from the given string."
-  (remove-postfix "-as2" (string-downcase string)))
+  (defun remove-as2-postfix (string)
+    "Remove the '-as2' prefix from the given string."
+    (remove-postfix "-as2" (string-downcase string)))
 
-(defun prepare-property-key (name)
-  (kebab-camel (remove-as2-postfix (string (symbol-name name)))))
+  (defun prepare-property-key (name)
+    (kebab-camel (remove-as2-postfix (string (symbol-name name))))))
 
 ;;; CLOS related stuff
 
@@ -314,3 +315,30 @@
 
 (define-extend-class ignore-as2
   block-as2)
+
+;;; Actor Types
+
+(define-extend-classes object
+  application
+  group
+  organization
+  person
+  service)
+
+;;; Object and Link Types
+
+(define-extend-classes object
+  relationship
+  article
+  document
+  event
+  place
+  profile
+  tombstone)
+
+(define-extend-classes document
+  audio
+  image
+  video
+  note
+  page)