diff --git a/.drone.yml b/.drone.yml
index 4310c84..f7b6ec6 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -12,11 +12,11 @@ steps:
   - name: compress
     image: alpine
     commands:
-    - ls -la
     - apk add gzip
     - cd /drone/src/resources/public/
-    - rm /drone/src/resources/public/*.gz
-    - rm /drone/src/resources/public/webfonts/*.gz
+    - rm -f /drone/src/resources/public/*.js
+    - rm -f /drone/src/resources/public/*.gz
+    - rm -f /drone/src/resources/public/webfonts/*.gz
     - gzip *.css *.js *.html *.png -k
     - gzip ./webfonts/*.woff2 -k
     - tar -czvf release.tar.gz *.gz ./webfonts/*.gz 
diff --git a/prod.cljs.edn b/prod.cljs.edn
index 93b4c86..822bca3 100644
--- a/prod.cljs.edn
+++ b/prod.cljs.edn
@@ -1,3 +1,3 @@
 {:output-to "resources/public/main.js"
-:optimizations :advanced
+ :optimizations :advanced
  :main weecfg.core}
diff --git a/resources/public/dev-main.js b/resources/public/dev-main.js
deleted file mode 100644
index a914af8..0000000
--- a/resources/public/dev-main.js
+++ /dev/null
@@ -1,12 +0,0 @@
-var CLOSURE_UNCOMPILED_DEFINES = {"figwheel.repl.connect_url":"ws:\/\/localhost:9500\/figwheel-connect?fwprocess=839c36&fwbuild=dev"};
-var CLOSURE_NO_DEPS = true;
-if(typeof goog == "undefined") document.write('<script src="/cljs-out/dev/goog/base.js"></script>');
-document.write('<script src="/cljs-out/dev/goog/deps.js"></script>');
-document.write('<script src="/cljs-out/dev/cljs_deps.js"></script>');
-document.write('<script>if (typeof goog == "undefined") console.warn("ClojureScript could not load :main, did you forget to specify :asset-path?");</script>');
-document.write('<script>goog.require("figwheel.core");</script>');
-document.write('<script>goog.require("figwheel.main");</script>');
-document.write('<script>goog.require("figwheel.repl.preload");</script>');
-document.write('<script>goog.require("devtools.preload");</script>');
-document.write('<script>goog.require("process.env");</script>');
-document.write('<script>goog.require("weecfg.core");</script>');
diff --git a/src/weecfg/core.cljs b/src/weecfg/core.cljs
index df23e51..b0f51e5 100644
--- a/src/weecfg/core.cljs
+++ b/src/weecfg/core.cljs
@@ -12,12 +12,13 @@
 (defonce form-title (atom "GASP Sensor setup"))
 (defonce form-data (atom {:server "" :device-id "" :wifi-ssid "" :wifi-key ""}))
 (defonce device-id-regex #"[A-Za-z0-9]{4}")
+(defonce alpha-numeric-regex #"[A-Za-z0-9]")
 (defonce ssid-regex #"^[!#;].|[+\[\]\"\t\s].*$")
 
 ; spec validation definitions
 (s/def ::boolean-type boolean?)
 (s/def ::integer-type int?)
-(s/def ::size-test #(<= (count %) 2))
+(s/def ::alpha-numeric-type (s/and string? #(re-matches alpha-numeric-regex %)))
 (s/def ::ssid-size-limit #(<= (count %) 32))
 (s/def ::default-size-limit #(<= (count %) 50))
 (s/def ::wifi-ssid-type (s/and string? #(re-matches ssid-regex %) ::ssid-size-limit))