diff --git a/pages/admin/users/auth/simple/index.vue b/pages/admin/users/auth/simple/index.vue
index 8d6a8ac..e58189f 100644
--- a/pages/admin/users/auth/simple/index.vue
+++ b/pages/admin/users/auth/simple/index.vue
@@ -360,6 +360,9 @@
                     :loading="loading"
                     type="submit"
                     class="w-full sm:w-fit"
+                    :disabled="
+                      !(validUsername && validEmail && username && email)
+                    "
                   >
                     {{ $t("users.admin.simple.inviteButton") }}
                   </LoadingButton>
diff --git a/server/api/v1/admin/auth/invitation/index.post.ts b/server/api/v1/admin/auth/invitation/index.post.ts
index 90ad5e7..d1e97ff 100644
--- a/server/api/v1/admin/auth/invitation/index.post.ts
+++ b/server/api/v1/admin/auth/invitation/index.post.ts
@@ -1,18 +1,14 @@
-import { type } from "arktype";
 import { readDropValidatedBody, throwingArktype } from "~/server/arktype";
 import aclManager from "~/server/internal/acls";
 import prisma from "~/server/internal/db/database";
+import { CreateUserValidator } from "../../../auth/signup/simple.post";
 
-const CreateInvite = type({
-  isAdmin: "boolean?",
-  username: "string?",
-  email: "string.email?",
-  expires: "string.date.iso.parse",
+const CreateInvite = CreateUserValidator.and({
+  expires: "Date",
+  isAdmin: "boolean = false",
 }).configure(throwingArktype);
 
-export default defineEventHandler<{
-  body: typeof CreateInvite.infer;
-}>(async (h3) => {
+export default defineEventHandler(async (h3) => {
   const allowed = await aclManager.allowSystemACL(h3, [
     "auth:simple:invitation:new",
   ]);
@@ -20,6 +16,8 @@ export default defineEventHandler<{
 
   const body = await readDropValidatedBody(h3, CreateInvite);
 
+  console.log(body);
+
   const invitation = await prisma.invitation.create({
     data: body,
   });
diff --git a/server/api/v1/auth/signup/simple.post.ts b/server/api/v1/auth/signup/simple.post.ts
index 5541ec3..4ff2a16 100644
--- a/server/api/v1/auth/signup/simple.post.ts
+++ b/server/api/v1/auth/signup/simple.post.ts
@@ -5,21 +5,22 @@ import * as jdenticon from "jdenticon";
 import objectHandler from "~/server/internal/objects";
 import { type } from "arktype";
 import { randomUUID } from "node:crypto";
+import { throwingArktype } from "~/server/arktype";
 
-const userValidator = type({
-  invitation: "string",
+export const CreateUserValidator = type({
+  invitation: "string?", // Optional because we re-use this validator
   username: "string >= 5",
   email: "string.email",
   password: "string >= 14",
   "displayName?": "string | undefined",
-});
+}).configure(throwingArktype);
 
 export default defineEventHandler<{
-  body: typeof userValidator.infer;
+  body: typeof CreateUserValidator.infer;
 }>(async (h3) => {
-  const body = await readBody(h3);
+  const user = await readValidatedBody(h3, CreateUserValidator);
 
-  const invitationId = body.invitation;
+  const invitationId = user.invitation;
   if (!invitationId)
     throw createError({
       statusCode: 401,
@@ -35,17 +36,6 @@ export default defineEventHandler<{
       statusMessage: "Invalid or expired invitation.",
     });
 
-  const user = userValidator(body);
-  if (user instanceof type.errors) {
-    // hover out.summary to see validation errors
-    console.error(user.summary);
-
-    throw createError({
-      statusCode: 400,
-      statusMessage: user.summary,
-    });
-  }
-
   // reuse items from invite
   if (invitation.username !== null) user.username = invitation.username;
   if (invitation.email !== null) user.email = invitation.email;