diff --git a/forum.nim b/forum.nim
index df5b5eb..3f951bc 100644
--- a/forum.nim
+++ b/forum.nim
@@ -14,7 +14,9 @@ import cgi except setCookie
 import options
 
 import redesign/threadlist except User
-import redesign/[category, postlist, error, header, post, profile, user]
+import redesign/[
+  category, postlist, error, header, post, profile, user, karaxutils
+]
 
 when not defined(windows):
   import bcrypt # TODO
@@ -297,63 +299,6 @@ proc setError(c: TForumData, field, msg: string): bool {.inline.} =
   c.errorMsg = "Error: " & msg
   return false
 
-proc register(c: TForumData, name, pass, antibot, userIp,
-              email: string): Future[bool] {.async.} =
-  # Username validation:
-  if name.len == 0 or not allCharsInSet(name, UsernameIdent):
-    return setError(c, "name", "Invalid username!")
-  if getValue(db, sql"select name from person where name = ?", name).len > 0:
-    return setError(c, "name", "Username already exists!")
-
-  # Password validation:
-  if pass.len < 4:
-    return setError(c, "new_password", "Invalid password!")
-
-  # captcha validation:
-  if useCaptcha:
-    var captchaValid: bool = false
-    try:
-      captchaValid = await captcha.verify(antibot, userIp)
-    except:
-      echo("[ERROR] Error checking captcha: " & getCurrentExceptionMsg())
-      captchaValid = false
-
-    if not captchaValid:
-      return setError(c, "g-recaptcha-response", "Answer to captcha incorrect!")
-
-  # email validation
-  if not ('@' in email and '.' in email):
-    return setError(c, "email", "Invalid email address")
-
-  # perform registration:
-  var salt = makeSalt()
-  let password = makePassword(pass, salt)
-
-  # Send activation email.
-  let epoch = $int(epochTime())
-  let activateUrl = c.req.makeUri("/activateEmail?nick=$1&epoch=$2&ident=$3" %
-      [encodeUrl(name), encodeUrl(epoch),
-       encodeUrl(makeIdentHash(name, password, epoch, salt))])
-
-  let emailSentFut = sendEmailActivation(c.config, email, name, activateUrl)
-  # Block until we send the email.
-  # TODO: This is a workaround for 'var T' not being usable in async procs.
-  while not emailSentFut.finished:
-    poll()
-  when not defined(dev):
-    if emailSentFut.failed:
-      echo("[WARNING] Couldn't send activation email: ", emailSentFut.error.msg)
-      return setError(c, "email", "Couldn't send activation email")
-
-  # add account to person table
-  exec(db,
-    sql("INSERT INTO person(name, password, email, salt, status, lastOnline) " &
-        "VALUES (?, ?, ?, ?, ?, DATETIME('now'))"), name,
-              password, email, salt,
-              when defined(dev): $Moderated else: $EmailUnconfirmed)
-
-  return true
-
 proc resetPassword(c: TForumData, nick, antibot, userIp: string): Future[bool] {.async.} =
   # captcha validation:
   if useCaptcha:
@@ -678,34 +623,6 @@ proc newThread(c: TForumData): bool =
           threadUrl=c.makeThreadURL())
     result = true
 
-proc login(c: TForumData, name, pass: string): bool =
-  # get form data:
-  const query =
-    sql"select id, name, password, email, salt, status, ban from person where name = ?"
-  if name.len == 0:
-    return c.setError("name", "Username cannot be nil.")
-  var success = false
-  for row in fastRows(db, query, name):
-    if row[2] == makePassword(pass, row[4], row[2]):
-      c.rank = parseEnum[Rank](row[5])
-      let ban = getBanErrorMsg(row[6], c.rank)
-      if ban.len > 0:
-        return c.setError("name", ban)
-      c.userid = row[0]
-      c.username = row[1]
-      c.userpass = row[2]
-      c.email = row[3]
-      success = true
-      break
-  if success:
-    # create session:
-    exec(db,
-      sql"insert into session (ip, password, userid) values (?, ?, ?)",
-      c.req.ip, c.userpass, c.userid)
-    return true
-  else:
-    return c.setError("password", "Login failed!")
-
 proc verifyIdentHash(c: TForumData, name, epoch, ident: string): bool =
   const query =
     sql"select password, salt, strftime('%s', lastOnline) from person where name = ?"
@@ -1154,6 +1071,81 @@ proc executeNewThread(c: TForumData, subject, msg: string): (int64, int64) =
   discard tryExec(db, sql"insert into post_fts(post_fts) values('optimize')")
   discard tryExec(db, sql"insert into post_fts(thread_fts) values('optimize')")
 
+proc executeLogin(c: TForumData, username, password: string): string =
+  ## Performs a login with the specified details.
+  ##
+  ## Optionally, `username` may contain the email of the user instead.
+  const query =
+    sql"""
+      select id, name, password, email, salt
+      from person where name = ? or email = ?
+    """
+  if username.len == 0:
+    raise newForumError("Username cannot be empty", @["username"])
+
+  for row in fastRows(db, query, username, username):
+    if row[2] == makePassword(password, row[4], row[2]):
+      exec(
+        db,
+        sql"insert into session (ip, password, userid) values (?, ?, ?)",
+        c.req.ip, row[2], row[0]
+      )
+      return row[2]
+
+  raise newForumError("Invalid username or password")
+
+proc executeRegister(c: TForumData, name, pass, antibot, userIp,
+                     email: string): Future[string] {.async.} =
+  ## Registers a new user and returns a new session key for that user's
+  ## session if registration was successful. Exceptions are raised otherwise.
+
+  # Username validation:
+  if name.len == 0 or not allCharsInSet(name, UsernameIdent):
+    raise newForumError("Invalid username", @["username"])
+  if getValue(db, sql"select name from person where name = ?", name).len > 0:
+    raise newForumError("Username already exists", @["username"])
+
+  # Password validation:
+  if pass.len < 4:
+    raise newForumError("Please choose a longer password", @["password"])
+
+  # captcha validation:
+  if useCaptcha:
+    var verifyFut = captcha.verify(antibot, userIp)
+    yield verifyFut
+    if verifyFut.failed:
+      raise newForumError(
+        "Invalid recaptcha answer", @[]
+      )
+
+  # email validation
+  if not ('@' in email and '.' in email):
+    raise newForumError("Invalid email", @["email"])
+
+  # perform registration:
+  var salt = makeSalt()
+  let password = makePassword(pass, salt)
+
+  # Send activation email.
+  let epoch = $int(epochTime())
+  let activateUrl = c.req.makeUri("/activateEmail?nick=$1&epoch=$2&ident=$3" %
+      [encodeUrl(name), encodeUrl(epoch),
+       encodeUrl(makeIdentHash(name, password, epoch, salt))])
+
+  let emailSentFut = sendEmailActivation(c.config, email, name, activateUrl)
+  yield emailSentFut
+  if emailSentFut.failed:
+    echo("[WARNING] Couldn't send activation email: ", emailSentFut.error.msg)
+    raise newForumError("Couldn't send activation email", @["email"])
+
+  # Add account to person table
+  exec(db,
+    sql("INSERT INTO person(name, password, email, salt, status, lastOnline) " &
+        "VALUES (?, ?, ?, ?, ?, DATETIME('now'))"), name,
+              password, email, salt, $Moderated)
+
+  return password
+
 initialise()
 
 routes:
@@ -1351,15 +1343,39 @@ routes:
   post "/karax/login":
     createTFD()
     let formData = request.formData
-    if login(c, formData["username"].body, formData["password"].body):
-      setCookie("sid", c.userpass)
-      resp Http200, "{}", "application/json"
-    else:
-      let err = PostError(
-        errorFields: @["username", "password"],
-        message: "Invalid username or password"
+    cond "username" in formData
+    cond "password" in formData
+    try:
+      let session = executeLogin(
+        c,
+        formData["username"].body,
+        formData["password"].body
       )
-      resp Http403, $(%err), "application/json"
+      setCookie("sid", session)
+      resp Http200, "{}", "application/json"
+    except ForumError as exc:
+      resp Http400, $(%exc.data), "application/json"
+
+  post "/karax/signup":
+    createTFD()
+    let formData = request.formData
+    let username = formData["username"].body
+    let password = formData["password"].body
+    try:
+      discard await executeRegister(
+        c,
+        username,
+        password,
+        formData["g-recaptcha-response"].body,
+        request.host,
+        formData["email"].body
+      )
+      let session = executeLogin(c, username, password)
+      setCookie("sid", session)
+      resp Http200, "{}", "application/json"
+    except ForumError:
+      let exc = (ref ForumError)(getCurrentException())
+      resp Http400, $(%exc.data), "application/json"
 
   get "/karax/status.json":
     createTFD()
@@ -1377,7 +1393,14 @@ routes:
       else:
         none[User]()
 
-    let status = UserStatus(user: user)
+    let status = UserStatus(
+      user: user,
+      recaptchaSiteKey:
+        if useCaptcha:
+          some(config.recaptchaSiteKey)
+        else:
+          none[string]()
+    )
     resp $(%status), "application/json"
 
   post "/karax/preview":
@@ -1566,27 +1589,6 @@ routes:
     resp genMain(c, body(), "Nim Forum - " &
                             (if c.isPreview: "Preview" else: "Error"))
 
-  post "/dologin":
-    createTFD()
-    if login(c, @"name", @"password"):
-      finishLogin()
-    else:
-      c.isThreadsList = true
-      var count = 0
-      let threadList = genThreadsList(c, count)
-      let data = genMain(c, threadList,
-          additionalHeaders = genRSSHeaders(c), showRssLinks = true)
-      resp data
-
-  post "/doregister":
-    createTFD()
-    if await c.register(@"name", @"new_password", @"g-recaptcha-response", request.host, @"email"):
-      resp genMain(c, "You are now registered. You must now confirm your" &
-          " email address by clicking the link sent to " & @"email",
-          "Registration successful - Nim Forum")
-    else:
-      resp c.genMain(genFormRegister(c))
-
   post "/donewthread":
     createTFD()
     if newThread(c):
diff --git a/redesign/error.nim b/redesign/error.nim
index af04e73..e921a1a 100644
--- a/redesign/error.nim
+++ b/redesign/error.nim
@@ -38,7 +38,8 @@ when defined(js):
 
         if not error.isNone:
           let e = error.get()
-          if (e.errorFields.len == 1 and e.errorFields[0] == name) or isLast:
+          if (e.errorFields.len == 1 and e.errorFields[0] == name) or
+             (isLast and e.errorFields.len == 0):
             p(class="form-input-hint"):
               text e.message
 
diff --git a/redesign/header.nim b/redesign/header.nim
index d594431..d4d764f 100644
--- a/redesign/header.nim
+++ b/redesign/header.nim
@@ -4,6 +4,7 @@ import threadlist, user
 type
   UserStatus* = object
     user*: Option[User]
+    recaptchaSiteKey*: Option[string]
 
 when defined(js):
   include karax/prelude
@@ -104,4 +105,5 @@ when defined(js):
       # Modals
       render(state.loginModal)
 
-      render(state.signupModal)
\ No newline at end of file
+      if state.data.isSome():
+        render(state.signupModal, state.data.get().recaptchaSiteKey)
\ No newline at end of file
diff --git a/redesign/karax.html b/redesign/karax.html
index aa4d440..8c35343 100644
--- a/redesign/karax.html
+++ b/redesign/karax.html
@@ -14,7 +14,6 @@
 </head>
 
 <body>
-
   <div id="ROOT" />
 
   <script type="text/javascript" src="/karax/nimcache/forum.js"></script>
diff --git a/redesign/karaxutils.nim b/redesign/karaxutils.nim
index eeb0e92..e34b7a2 100644
--- a/redesign/karaxutils.nim
+++ b/redesign/karaxutils.nim
@@ -1,5 +1,4 @@
 import strutils, options, strformat, parseutils
-import dom except window
 
 proc parseInt*(s: string, value: var int, validRange: Slice[int]) {.
   noSideEffect.} =
@@ -23,6 +22,8 @@ when defined(js):
   include karax/prelude
   import karax / [kdom]
 
+  import dom except window
+
   const appName = "/karax/"
 
   proc class*(classes: varargs[tuple[name: string, present: bool]],
diff --git a/redesign/nimforum.scss b/redesign/nimforum.scss
index 169e2b9..cc823b5 100644
--- a/redesign/nimforum.scss
+++ b/redesign/nimforum.scss
@@ -553,4 +553,12 @@ hr {
   &:hover, &:focus {
     text-shadow: $body-font-color 0px 0px 0px;
   }
+}
+
+// - Sign up modal
+
+#signup-modal {
+  .modal-container .modal-body {
+    max-height: 60vh;
+  }
 }
\ No newline at end of file
diff --git a/redesign/signup.nim b/redesign/signup.nim
index 1b0db46..93ac84f 100644
--- a/redesign/signup.nim
+++ b/redesign/signup.nim
@@ -11,29 +11,17 @@ when defined(js):
   type
     SignupModal* = ref object
       shown: bool
+      loading: bool
       onSignUp, onLogIn: proc ()
       error: Option[PostError]
 
   proc onSignUpPost(httpStatus: int, response: kstring, state: SignupModal) =
-    let status = httpStatus.HttpCode
-    if status == Http200:
+    postFinished:
       state.shown = false
       state.onSignUp()
-    else:
-      # TODO: Karax should pass the content-type...
-      try:
-        let parsed = parseJson($response)
-        let error = to(parsed, PostError)
-
-        state.error = some(error)
-      except:
-        kout(getCurrentExceptionMsg().cstring)
-        state.error = some(PostError(
-          errorFields: @[],
-          message: "Unknown error occurred."
-        ))
 
   proc onSignUpClick(ev: Event, n: VNode, state: SignupModal) =
+    state.loading = true
     state.error = none[PostError]()
 
     let uri = makeUri("signup")
@@ -57,9 +45,11 @@ when defined(js):
   proc show*(state: SignupModal) =
     state.shown = true
 
-  proc render*(state: SignupModal): VNode =
+  proc render*(state: SignupModal, recaptchaSiteKey: Option[string]): VNode =
+    setForeignNodeId("recaptcha")
+
     result = buildHtml():
-      tdiv(class=class({"active": state.shown}, "modal modal-sm"),
+      tdiv(class=class({"active": state.shown}, "modal"),
            id="signup-modal"):
         a(href="", class="modal-overlay", "aria-label"="close",
           onClick=(ev: Event, n: VNode) => onClose(ev, n, state))
@@ -82,8 +72,13 @@ when defined(js):
                   "password",
                   true
                 )
+                if recaptchaSiteKey.isSome:
+                  tdiv(id="recaptcha"):
+                    tdiv(class="g-recaptcha",
+                         "data-sitekey"=recaptchaSiteKey.get())
+                    script(src="https://www.google.com/recaptcha/api.js")
           tdiv(class="modal-footer"):
-            button(class="btn btn-primary",
+            button(class=class({"loading": state.loading}, "btn btn-primary"),
                   onClick=(ev: Event, n: VNode) => onSignUpClick(ev, n, state)):
               text "Create account"
             button(class="btn",