diff --git a/project.clj b/project.clj
index d7c0230..48c4131 100644
--- a/project.clj
+++ b/project.clj
@@ -1,24 +1,118 @@
 (defproject dog-and-duck/quack "0.1.0-SNAPSHOT"
+  :aliases {"test-cljs" ["with-profile" "test" "doo" "rhino" "test" "once"]
+            "test-all"  ["do" ["test"] ["test-cljs"]]}
+  :cljsbuild {:builds
+              [{:id "dev"
+                :source-paths ["src"]
+
+                ;; The presence of a :figwheel configuration here
+                ;; will cause figwheel to inject the figwheel client
+                ;; into your build
+                :figwheel {:on-jsload "froboz.core/on-js-reload"
+                           ;; :open-urls will pop open your application
+                           ;; in the default browser once Figwheel has
+                           ;; started and compiled your application.
+                           ;; Comment this out once it no longer serves you.
+                           :open-urls ["http://localhost:3449/index.html"]}
+
+                :compiler {:main froboz.core
+                           :asset-path "js/compiled/out"
+                           :output-to "resources/public/js/compiled/froboz.js"
+                           :output-dir "resources/public/js/compiled/out"
+                           :source-map-timestamp true
+                           ;; To console.log CLJS data-structures make sure you enable devtools in Chrome
+                           ;; https://github.com/binaryage/cljs-devtools
+                           :preloads [devtools.preload]}}
+               ;; This next build is a compressed minified build for
+               ;; production. You can build this with:
+               ;; lein cljsbuild once min
+               {:id "min"
+                :source-paths ["src"]
+                :compiler {:output-to "resources/public/js/compiled/froboz.js"
+                           :main froboz.core
+                           :optimizations :advanced
+                           :pretty-print false}}]}
+
   :cloverage {:output "docs/cloverage"
               :codecov? true
               :emma-xml? true}
-:codox {:metadata {:doc "**TODO**: write docs"
-                   :doc/format :markdown}
-        :output-path "docs/codox"
-        :source-uri "https://github.com/simon-brooke/quack/blob/master/{filepath}#L{line}"}
+  :codox {:metadata {:doc "**TODO**: write docs"
+                     :doc/format :markdown}
+          :output-path "docs/codox"
+          :source-uri "https://github.com/simon-brooke/quack/blob/master/{filepath}#L{line}"}
   :dependencies [[com.taoensso/timbre "6.0.4"]
                  [hiccup "1.0.5"]
                  [mvxcvi/clj-pgp "1.1.0"]
                  [org.clojars.simon_brooke/internationalisation "1.0.5"]
                  [org.clojure/clojure "1.10.3"]
+                 [org.clojure/clojurescript "1.10.773"]
+                 [org.clojure/core.async  "0.4.500"]
                  [org.clojure/data.json "2.4.0"]
                  [org.clojure/tools.cli "1.0.214"]
                  [trptr/java-wrapper "0.2.3"]]
   :description "A validator for ActivityStreams."
+  :doo {:paths {:rhino "lein run -m org.mozilla.javascript.tools.shell.Main"}}
+
+  :figwheel {;; :http-server-root "public" ;; default and assumes "resources"
+             ;; :server-port 3449 ;; default
+             ;; :server-ip "127.0.0.1"
+
+             :css-dirs ["resources/public/css"] ;; watch and update CSS
+
+             ;; Start an nREPL server into the running figwheel process
+             ;; :nrepl-port 7888
+
+             ;; Server Ring Handler (optional)
+             ;; if you want to embed a ring handler into the figwheel http-kit
+             ;; server, this is for simple ring servers, if this
+
+             ;; doesn't work for you just run your own server :) (see lein-ring)
+
+             ;; :ring-handler hello_world.server/handler
+
+             ;; To be able to open files in your editor from the heads up display
+             ;; you will need to put a script on your path.
+             ;; that script will have to take a file path and a line number
+             ;; ie. in  ~/bin/myfile-opener
+             ;; #! /bin/sh
+             ;; emacsclient -n +$2 $1
+             ;;
+             ;; :open-file-command "myfile-opener"
+
+             ;; if you are using emacsclient you can just use
+             ;; :open-file-command "emacsclient"
+
+             ;; if you want to disable the REPL
+             ;; :repl false
+
+             ;; to configure a different figwheel logfile path
+             ;; :server-logfile "tmp/logs/figwheel-logfile.log"
+
+             ;; to pipe all the output to the repl
+             ;; :server-logfile false
+             }
   :license {:name "GPL-2.0-or-later"
             :url "https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html"}
   :main ^:skip-aot dog-and-duck.quack.core
-  :profiles {:uberjar {:aot :all
+  :plugins [[lein-cljsbuild "1.1.3"]
+            [lein-doo "0.1.6"]]
+  :profiles {:dev {:dependencies [[binaryage/devtools "1.0.0"]
+                                  [figwheel-sidecar "0.5.20"]]
+                   ;; need to add dev source path here to get user.clj loaded
+                   :source-paths ["src/cljs" "src/cljc" "dev"]
+                   ;; need to add the compiled assets to the :clean-targets
+                   :clean-targets ^{:protect false} ["resources/public/js/compiled"
+                                                     :target-path]}
+             :test {:dependencies [[org.mozilla/rhino "1.7.7"]]
+                    :cljsbuild
+                    {:builds
+                     {:test
+                      {:source-paths ["src" "test"]
+                       :compiler {:output-to "target/main.js"
+                                  :output-dir "target"
+                                  ;; :main {{top-namespace}}.test-runner
+                                  :optimizations :simple}}}}}
+             :uberjar {:aot :all
                        :jvm-opts ["-Dclojure.compiler.direct-linking=true"]}}
   :repl-options {:init-ns dog-and-duck.quack.core}
   :target-path "target/%s"
diff --git a/src/dog_and_duck/quack/constants.clj b/src/clj/dog_and_duck/quack/constants.clj
similarity index 100%
rename from src/dog_and_duck/quack/constants.clj
rename to src/clj/dog_and_duck/quack/constants.clj
diff --git a/src/dog_and_duck/quack/control_variables.clj b/src/clj/dog_and_duck/quack/control_variables.clj
similarity index 100%
rename from src/dog_and_duck/quack/control_variables.clj
rename to src/clj/dog_and_duck/quack/control_variables.clj
diff --git a/src/dog_and_duck/quack/core.clj b/src/clj/dog_and_duck/quack/core.clj
similarity index 100%
rename from src/dog_and_duck/quack/core.clj
rename to src/clj/dog_and_duck/quack/core.clj
diff --git a/src/dog_and_duck/quack/objects.clj b/src/clj/dog_and_duck/quack/objects.clj
similarity index 95%
rename from src/dog_and_duck/quack/objects.clj
rename to src/clj/dog_and_duck/quack/objects.clj
index 5a4fa54..85b4a41 100644
--- a/src/dog_and_duck/quack/objects.clj
+++ b/src/clj/dog_and_duck/quack/objects.clj
@@ -1,6 +1,8 @@
 (ns dog-and-duck.quack.objects
   (:require [clojure.data.json :as json]
+            [clojure.pprint :refer [pprint]]
             [clojure.set :refer [union]]
+            [clojure.string :refer [join]]
             [clojure.walk :refer [keywordize-keys]]
             [dog-and-duck.quack.constants :refer [actor-types
                                                   noun-types
@@ -20,7 +22,7 @@
                                               object-or-uri?
                                               truthy?
                                               xsd-non-negative-integer?]]
-            [taoensso.timbre :refer [warn]])
+            [taoensso.timbre :refer [info warn error]])
   (:import [java.io FileNotFoundException]
            [java.net URI URISyntaxException]))
 
@@ -138,6 +140,35 @@
              :severity severity
              :token token}))))
 
+(defn- percentage-value?
+  "Return `true` if `x` is a number between 0 and 100 inclusive, else
+   `false`."
+  [x]
+  (try (and (xsd-float? x)
+            (>= x 0)
+            (<= x 100))
+       (catch Exception any
+         (error (join " "
+                      ["Unexpected value ("
+                       x
+                       ") passed to `percentage-value?`:"
+                       (-> any .getClass .getName)
+                       ":" (.getMessage any)]))
+         false)))
+
+(defn positive?
+  "Return `true` if `x` is a number which is greater than 0, else `false`"
+  [x]
+  (try
+    (pos? x)
+    (catch Exception any
+      (error (join " "
+                   ["Unexpected value ("
+                    x
+                    ") passed to `positive?`:"
+                    (-> any .getClass .getName)
+                    ":" (.getMessage any)]))
+      false)))
 
 (def object-expected-properties
   "Requirements of properties of object, cribbed from
@@ -162,9 +193,7 @@
       which will be applied to the value or values of the identified property."
   {:accuracy {:functional false
               :if-invalid [:must :invalid-number]
-              :validator (fn [pv] (and (xsd-float? pv)
-                                       (>= pv 0)
-                                       (<= pv 100)))}
+              :validator percentage-value?}
    :actor {:functional false
            :if-invalid [:must :invalid-actor]
            :if-missing [:must :no-actor]
@@ -435,7 +464,7 @@
                                                              :invalid-replies))}
    :radius {:functional true
             :if-invalid [:must :invalid-positive-number]
-            :validator (fn [pv] (and (xsd-float? pv) (> pv 0)))}
+            :validator positive?}
    :rel {:functional false
          :if-invalid [:must :invalid-link-relation]
          ;; TODO: this is not really good enough.
@@ -526,6 +555,11 @@
    return `nil` if no faults are found, else a list of faults."
   [obj prop clause]
   ;; (info "obj" obj "prop" prop "clause" clause)
+  (info (join " " ["Checking validity of property" 
+                   prop "of object\n" (with-out-str 
+                                        (pprint obj))
+                   "\nusing clause\n"
+                   (with-out-str (pprint clause))]))
   (let [val (obj prop)
         validator (:validator clause)
         [severity token] (:if-invalid clause)]
diff --git a/src/dog_and_duck/quack/scratch.clj b/src/clj/dog_and_duck/quack/scratch.clj
similarity index 81%
rename from src/dog_and_duck/quack/scratch.clj
rename to src/clj/dog_and_duck/quack/scratch.clj
index f40107b..20fc094 100644
--- a/src/dog_and_duck/quack/scratch.clj
+++ b/src/clj/dog_and_duck/quack/scratch.clj
@@ -1,6 +1,9 @@
 (ns dog-and-duck.quack.scratch
   "Development scratchpad"
-  (:require [dog-and-duck.quack.objects :refer [object-expected-properties]]
+  (:require [clojure.data.json :refer [read-str]]
+            [clojure.pprint :refer [pprint]]
+            [clojure.walk :refer [keywordize-keys]]
+            [dog-and-duck.quack.objects :refer [object-expected-properties]]
             [dog-and-duck.quack.utils :refer [concat-non-empty]]))
 
 (defn missing-messages
@@ -20,4 +23,9 @@
 ;;                               {:@context "https://simon-brooke.github.io/dog-and-duck/codox/Validation_Faults.html", 
 ;;                                :id "https://illuminator.local/fault/25785:1673378166063", :type "Fault", :severity :minor, :fault :no-id-transient, :narrative "The ActivityPub specification allows objects without `id` fields only if they are intentionally transient; even so it is preferred that the object should have an explicit null id."} 
 ;;                               ({:@context "https://simon-brooke.github.io/dog-and-duck/codox/Validation_Faults.html", 
-;;                                 :id "https://illuminator.local/fault/25785:1673378166069", :type "Fault", :severity :must, :fault :invalid-type, :narrative "invalid-type"})), :severity :info}})
\ No newline at end of file
+;;                                 :id "https://illuminator.local/fault/25785:1673378166069", :type "Fault", :severity :must, :fault :invalid-type, :narrative "invalid-type"})), :severity :info}})
+
+(def obj (keywordize-keys 
+          (read-str 
+           (slurp "../dog-and-duck/resources/activitystreams-test-documents//vocabulary-ex190-jsonld.json")
+           )))
diff --git a/src/dog_and_duck/quack/time.clj b/src/clj/dog_and_duck/quack/time.clj
similarity index 100%
rename from src/dog_and_duck/quack/time.clj
rename to src/clj/dog_and_duck/quack/time.clj
diff --git a/src/dog_and_duck/quack/utils.clj b/src/clj/dog_and_duck/quack/utils.clj
similarity index 100%
rename from src/dog_and_duck/quack/utils.clj
rename to src/clj/dog_and_duck/quack/utils.clj