diff --git a/validator.coffee b/validator.coffee
new file mode 100644
index 0000000..8c199d8
--- /dev/null
+++ b/validator.coffee
@@ -0,0 +1,50 @@
+valid_email_local_part = (lpart) ->
+    if lpart is undefined || lpart.length == 0 || lpart.length >64
+        return false
+    # Localpart is one or more atext pieces separated by .s
+    return lpart.match(/^[a-zA-Z0-9!#\$\%&'*+\-/=?^_`{|}~]+(?:\.[a-zA-Z0-9!#\$\%&'*+\-/=?^_`{|}~]+)*$/)
+
+valid_domain_label = (label) ->
+    if label is undefined || label.length > 63 || label.length == 0
+        return false
+    return label.match(/^[a-zA-Z0-9](?:[-a-zA-Z0-9]*[a-zA-Z0-9])?$/)
+
+valid_email_domain = (domain) ->
+    if domain is undefined || domain.length > 255 || domain.length == 0
+        return false
+    # a domain is one or more domain labels separated by .s
+    labels = domain.split(/\./)
+    return ($.grep( labels, (l)->return !valid_domain_label(l) )).length == 0
+
+valid_email = (email) ->
+    parts = email.split('@')
+    return false if !valid_email_local_part(parts[0])
+    return valid_email_domain(parts[1])
+
+display_error_unless = (condition, index) ->
+    select = '.errors li:eq(' + index + ')'
+    if(condition)
+        $(select).hide()
+    else
+        $(select).show()
+
+
+$(() ->
+  $('.errors li').hide()
+  $('input[type="text"]').blur((evt) ->
+      email = evt.target.value
+      display_error_unless( valid_email(email), 0 )
+  )
+  $('input[type="password"]').blur((evt) ->
+     password = evt.target.value
+     display_error_unless( password.length >= 8, 1 )
+     display_error_unless( password.match(/[A-Z]/), 2 )
+     display_error_unless( password.match(/\d/), 3 )
+  )
+  $('form[name="sign_in"]').submit((evt) ->
+    if $('.errors li').is(':visible')
+        evt.preventDefault()
+        return false
+    return true
+  )
+)
diff --git a/validator.js b/validator.js
index 860dab4..3dd17c1 100644
--- a/validator.js
+++ b/validator.js
@@ -1,7 +1,72 @@
+// Generated by CoffeeScript 1.10.0
+(function() {
+  var display_error_unless, valid_domain_label, valid_email, valid_email_domain, valid_email_local_part;
 
-  //insert your code here
- 
-$(function(){
+  valid_email_local_part = function(lpart) {
+    if (lpart === void 0 || lpart.length === 0 || lpart.length > 64) {
+      return false;
+    }
+    return lpart.match(/^[a-zA-Z0-9!#\$\%&'*+\-\/=?^_`{|}~]+(?:\.[a-zA-Z0-9!#\$\%&'*+\-\/=?^_`{|}~]+)*$/);
+  };
 
-  //insert your code here
-});
+  valid_domain_label = function(label) {
+    if (label === void 0 || label.length > 63 || label.length === 0) {
+      return false;
+    }
+    return label.match(/^[a-zA-Z0-9](?:[-a-zA-Z0-9]*[a-zA-Z0-9])?$/);
+  };
+
+  valid_email_domain = function(domain) {
+    var labels;
+    if (domain === void 0 || domain.length > 255 || domain.length === 0) {
+      return false;
+    }
+    labels = domain.split(/\./);
+    return ($.grep(labels, function(l) {
+      return !valid_domain_label(l);
+    })).length === 0;
+  };
+
+  valid_email = function(email) {
+    var parts;
+    parts = email.split('@');
+    if (!valid_email_local_part(parts[0])) {
+      return false;
+    }
+    return valid_email_domain(parts[1]);
+  };
+
+  display_error_unless = function(condition, index) {
+    var select;
+    select = '.errors li:eq(' + index + ')';
+    if (condition) {
+      return $(select).hide();
+    } else {
+      return $(select).show();
+    }
+  };
+
+  $(function() {
+    $('.errors li').hide();
+    $('input[type="text"]').blur(function(evt) {
+      var email;
+      email = evt.target.value;
+      return display_error_unless(valid_email(email), 0);
+    });
+    $('input[type="password"]').blur(function(evt) {
+      var password;
+      password = evt.target.value;
+      display_error_unless(password.length >= 8, 1);
+      display_error_unless(password.match(/[A-Z]/), 2);
+      return display_error_unless(password.match(/\d/), 3);
+    });
+    return $('form[name="sign_in"]').submit(function(evt) {
+      if ($('.errors li').is(':visible')) {
+        evt.preventDefault();
+        return false;
+      }
+      return true;
+    });
+  });
+
+}).call(this);