diff --git a/sentry.rb b/sentry.rb
index 04ec982..d0c288d 100644
--- a/sentry.rb
+++ b/sentry.rb
@@ -3,6 +3,7 @@ require 'xmpp4r'
 require 'net/smtp'
 require 'json'
 require 'uri'
+require 'openssl'
 
 norxondor_gorgonax = URI::MailTo::EMAIL_REGEXP
 
@@ -17,11 +18,18 @@ SMTP_TLS = CONFIG["tls"]
 SMTP_STARTTLS = CONFIG["starttls"]
 SMTP_AUTH = CONFIG["auth"].to_sym
 JABBER_SERVER = CONFIG["jabber-server"]
+JABBER_HOST = CONFIG['jabber-host']
+JABBER_PORT = CONFIG['jabber-port']
 HTTP_SERVER_ROOT = CONFIG['http-server-root']
+RATELIMIT = CONFIG['ratelimit']
+HTTP_PORT = CONFIG['http-port']
 
 Pending = {}
 Pending_by_username = {}
 
+Recent = {}
+
+# Get root path to redirect to
 def myroot(req)
   if req.ssl? then
     return "https://#{HTTP_SERVER_ROOT}"
@@ -30,9 +38,7 @@ def myroot(req)
   end
 end
 
-def register(username,password)
-  cl = Jabber::Client.new(Jabber::JID.new(
-
+# Send email with given SMTP config
 def sendmail(code,email) 
   smtp = Net::SMTP.new(SMTP_SERVER, SMTP_PORT)
   msg_headers = ''
@@ -47,7 +53,9 @@ def sendmail(code,email)
   puts(smtp.send_message msg, SMTP_USER, [email])
 end 
 
-server = Hyde::Server.new Port: 8001 do
+# Main API server
+server = Hyde::Server.new Port: HTTP_PORT do
+  # Serve static shit
   path "register" do
     preprocess do |ctx|
       puts "#{ctx.request.remote_ip} is registering"
@@ -57,51 +65,78 @@ server = Hyde::Server.new Port: 8001 do
     index ['index.html']
     serve "*.html"
   end
+  # API itself
   path "api" do
+    # First step
     post 'register' do |ctx|
+      # Where to redirect to
       server_uri = myroot ctx.request
-      # Add pending user
+      # Pending user info and validation key
       key = (1..32).map { |x| "0123456789ABCDEF"[(rand()*15).round] }.join
       user = ctx.request.query['user']
       password = ctx.request.query['password']
       email = ctx.request.query['email']
+      # Expiration is 2 hours from now 
       expires_on = Time.now+60*60*2
+      # Match query parameters against given rules
       unless user.match /^[\w_-]+$/ and
              email.match norxondor_gorgonax and
              password.match /^.{8,}$/ then
         redirect server_uri+"/register/error.html"
       end
+      # Bounce if user is already pending registration
       if Pending_by_username[user] then
         redirect server_uri+"/register/error.html"
       end
+      # Bounce if email is recent 
+      email_digest = OpenSSL::Digest.digest("sha256",email) 
+      if Recent[email_digest] then 
+        if Time.now < (Recent[email_digest]+RATELIMIT) then
+          redirect server_uri+"/register/ratelimit.html"
+        end
+      end
+      # Lock registration for pending user
       Pending_by_username[user] = Pending[key] = {
         "user" => user,
         "password" => password,
         "expires_on" => expires_on
       }
+      # Record recent emails that tried registering
+      Recent[email_digest] = Time.now
       begin
+        # Send email to validate
         sendmail(key,email)
         redirect server_uri+"/register/validate.html"
       rescue Exception => e
+        # Couldn't send email - delete pending account info
+        Pending_by_username.delete (Pending.delete key)["user"]
         redirect server_uri+"/register/error.html"
       end
     end
+    # Second step
     post 'validate' do |ctx|
+      # Where to redirect to
       server_uri = myroot ctx.request
+      # Validation key
       key = ctx.request.query['key']
+      # If validation key matches a user
       if Pending.has_key? key then
-        if Pending[key].expires_on < Time.now then
-          puts "#{Pending.delete key} expired"
+        # ... and if it's not expired
+        if Pending[key]["expires_on"] < Time.now then
+          # key has expired
+          puts "#{ctx.request.remote_ip} expired"
           redirect server_uri+"/register/error.html"
         end
+        # register the user
         cl = Jabber::Client.new(Jabber::JID.new(Pending[key]["user"]+"@"+JABBER_SERVER))
-        cl.connect
+        cl.connect JABBER_HOST, JABBER_PORT
         cl.register(Pending[key]["password"])
         cl.close
-        puts "#{Pending[key]} successfully verified"
+        puts "#{ctx.request.remote_ip} successfully verified"
         redirect server_uri+"/register/success.html"
       else
-        puts "#{Pending[key]} failed to verify"
+        # key is invalid
+        puts "#{ctx.request.remote_ip} failed to verify"
         redirect server_uri+"/register/error.html"
       end
     end
diff --git a/static/ratelimit.html b/static/ratelimit.html
new file mode 100644
index 0000000..8a5849f
--- /dev/null
+++ b/static/ratelimit.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <title> Registration form </title>
+    </head>
+    <body>
+        <h1> Oops! </h1>
+        <hr />
+        <p> You have been ratelimited! </p>
+    </body>
+</html>
+