AudiusProject · raymondjacobson · Jun 23, 2026
diff --git a/packages/common/src/api/tan-query/queryKeys.ts b/packages/common/src/api/tan-query/queryKeys.ts
@@ -45,7 +45,6 @@ export const QUERY_KEYS = {
   sales: 'sales',
   salesCount: 'salesCount',
   mutualFollowers: 'mutualFollowers',
-  emailInUse: 'emailInUse',
   handleInUse: 'handleInUse',
   handleReservedStatus: 'handleReservedStatus',
   search: 'search',

diff --git a/packages/common/src/api/tan-query/users/useEmailInUse.ts b/packages/common/src/api/tan-query/users/useEmailInUse.ts
diff --git a/packages/common/src/hooks/purchaseContent/usePurchaseContentFormConfiguration.ts b/packages/common/src/hooks/purchaseContent/usePurchaseContentFormConfiguration.ts
@@ -1,12 +1,10 @@
 import { useCallback, useEffect, useMemo } from 'react'
 
 import { USDC, UsdcWei } from '@audius/fixed-decimal'
-import { useQueryClient } from '@tanstack/react-query'
 import { useDispatch, useSelector } from 'react-redux'
 import { z } from 'zod'
 
 import { useCurrentAccount, useCurrentAccountUser, useUSDCBalance } from '~/api'
-import { useQueryContext } from '~/api/tan-query/utils/QueryContext'
 import { UserCollectionMetadata } from '~/models'
 import { PurchaseMethod, PurchaseVendor } from '~/models/PurchaseContent'
 import { UserTrackMetadata } from '~/models/Track'
@@ -53,9 +51,6 @@ export const usePurchaseContentFormConfiguration = ({
   presetValues: PayExtraAmountPresetValues
   purchaseVendor?: PurchaseVendor
 }) => {
-  const queryClient = useQueryClient()
-  const queryContext = useQueryContext()
-
   const dispatch = useDispatch()
   const isAlbum = isContentCollection(metadata)
   const isTrack = isContentTrack(metadata)
@@ -99,14 +94,8 @@ export const usePurchaseContentFormConfiguration = ({
       : undefined
 
   const validationSchema = useMemo(
-    () =>
-      createPurchaseContentSchema(
-        queryContext,
-        queryClient,
-        page,
-        guestEmail ?? undefined
-      ),
-    [queryContext, queryClient, guestEmail, page]
+    () => createPurchaseContentSchema(page),
+    [page]
   )
   type PurchaseContentValues = z.input<typeof validationSchema>
 

diff --git a/packages/common/src/hooks/purchaseContent/validation.ts b/packages/common/src/hooks/purchaseContent/validation.ts
@@ -1,9 +1,5 @@
-import { QueryClient } from '@tanstack/react-query'
 import { z } from 'zod'
 
-import { QUERY_KEYS } from '~/api'
-import { fetchEmailInUse } from '~/api/tan-query/users/useEmailInUse'
-import { QueryContextType } from '~/api/tan-query/utils/QueryContext'
 import { PurchaseMethod, PurchaseVendor } from '~/models/PurchaseContent'
 import { PurchaseContentPage } from '~/store'
 
@@ -21,20 +17,10 @@ import {
 import { PayExtraPreset } from './types'
 
 export const messages = {
-  amountInvalid: 'Please specify an amount between $1 and $100',
-  emailRequired: 'Please enter an email.',
-  invalidEmail: 'Please enter a valid email.',
-  emailInUse: 'Email already taken.',
-  somethingWentWrong: 'Something went wrong. Try again later.',
-  guestAccountExists: 'Guest account exists.'
+  amountInvalid: 'Please specify an amount between $1 and $100'
 }
 
-export const createPurchaseContentSchema = (
-  queryContext: QueryContextType,
-  queryClient: QueryClient,
-  page: PurchaseContentPage,
-  emailFromLocalStorage?: string
-) => {
+export const createPurchaseContentSchema = (page: PurchaseContentPage) => {
   return z
     .object({
       [CUSTOM_AMOUNT]: z
@@ -77,39 +63,4 @@ export const createPurchaseContentSchema = (
         path: [GUEST_EMAIL] // Specify the path to the error
       }
     )
-    .superRefine(async ({ guestEmail }, ctx) => {
-      if (
-        page !== PurchaseContentPage.GUEST_CHECKOUT ||
-        !guestEmail ||
-        guestEmail === emailFromLocalStorage
-      ) {
-        // only validate email if on guest checkout page and email is different
-        return
-      }
-
-      const { exists: isEmailInUse, isGuest } = await queryClient.fetchQuery({
-        queryKey: [QUERY_KEYS.emailInUse, guestEmail],
-        queryFn: async () => await fetchEmailInUse(guestEmail, queryContext)
-      })
-
-      if (isEmailInUse === undefined) {
-        ctx.addIssue({
-          code: z.ZodIssueCode.custom,
-          message: messages.somethingWentWrong,
-          path: [GUEST_EMAIL]
-        })
-      } else if (isGuest) {
-        ctx.addIssue({
-          code: z.ZodIssueCode.custom,
-          message: messages.guestAccountExists,
-          path: [GUEST_EMAIL]
-        })
-      } else if (isEmailInUse) {
-        ctx.addIssue({
-          code: z.ZodIssueCode.custom,
-          message: messages.emailInUse,
-          path: [GUEST_EMAIL]
-        })
-      }
-    })
 }
diff --git a/packages/common/src/hooks/useChangeEmailFormConfiguration.ts b/packages/common/src/hooks/useChangeEmailFormConfiguration.ts
@@ -1,6 +1,5 @@
 import { useState, useCallback, useMemo } from 'react'
 
-import { useQueryClient } from '@tanstack/react-query'
 import { FormikHelpers } from 'formik'
 import { z } from 'zod'
 import { toFormikValidationSchema } from 'zod-formik-adapter'
@@ -55,7 +54,6 @@ export const useChangeEmailFormConfiguration = (onComplete: () => void) => {
   const [page, setPage] = useState(ChangeEmailPage.ConfirmPassword)
   const queryContext = useQueryContext()
   const { authService } = queryContext
-  const queryClient = useQueryClient()
 
   // Move schema initializations inside the hook to prevent initialization timing issues
   const confirmPasswordFormikSchema = toFormikValidationSchema(
@@ -67,10 +65,7 @@ export const useChangeEmailFormConfiguration = (onComplete: () => void) => {
   )
   const verifyEmailFormikSchema = toFormikValidationSchema(confirmEmailSchema)
 
-  const EmailSchema = useMemo(
-    () => toFormikValidationSchema(emailSchema(queryContext, queryClient)),
-    [queryContext, queryClient]
-  )
+  const EmailSchema = useMemo(() => toFormikValidationSchema(emailSchema()), [])
 
   const validationSchema =
     page === ChangeEmailPage.ConfirmPassword

diff --git a/packages/common/src/schemas/sign-on/emailSchema.ts b/packages/common/src/schemas/sign-on/emailSchema.ts
@@ -1,49 +1,15 @@
-import { QueryClient } from '@tanstack/react-query'
 import { z } from 'zod'
 
-import { QUERY_KEYS, QueryContextType } from '~/api'
-import { fetchEmailInUse } from '~/api/tan-query/users/useEmailInUse'
 import { EMAIL_REGEX } from '~/utils/email'
 
 export const emailSchemaMessages = {
   emailRequired: 'Please enter an email.',
-  invalidEmail: 'Please enter a valid email.',
-  emailInUse: 'Email already taken.',
-  somethingWentWrong: 'Something went wrong. Try again later.',
-  guestAccountExists: 'Guest account exists.'
+  invalidEmail: 'Please enter a valid email.'
 }
 
-export const emailSchema = (
-  queryContext: QueryContextType,
-  queryClient: QueryClient
-) =>
+export const emailSchema = () =>
   z.object({
     email: z
       .string({ required_error: emailSchemaMessages.emailRequired })
       .regex(EMAIL_REGEX, { message: emailSchemaMessages.invalidEmail })
-      .superRefine(async (email, ctx) => {
-        const { exists: isEmailInUse, isGuest } = await queryClient.fetchQuery({
-          queryKey: [QUERY_KEYS.emailInUse, email],
-          queryFn: async () => await fetchEmailInUse(email, queryContext)
-        })
-        if (isEmailInUse === undefined) {
-          ctx.addIssue({
-            code: z.ZodIssueCode.custom,
-            message: emailSchemaMessages.somethingWentWrong
-          })
-        } else if (isGuest) {
-          // complete guest accounts only
-          ctx.addIssue({
-            code: z.ZodIssueCode.custom,
-            message: emailSchemaMessages.guestAccountExists
-          })
-          return true
-        } else if (isEmailInUse) {
-          ctx.addIssue({
-            code: z.ZodIssueCode.custom,
-            message: emailSchemaMessages.emailInUse
-          })
-        }
-        return z.NEVER // The return value is not used, but we need to return something to satisfy the typing
-      })
   })
diff --git a/packages/common/src/schemas/sign-on/signInSchema.ts b/packages/common/src/schemas/sign-on/signInSchema.ts
@@ -1,42 +1,17 @@
-import { QueryClient } from '@tanstack/react-query'
 import { z } from 'zod'
 
-import { QUERY_KEYS } from '~/api'
-import { fetchEmailInUse } from '~/api/tan-query/users/useEmailInUse'
-import { QueryContextType } from '~/api/tan-query/utils'
-
 export const messages = {
   emailRequired: 'Please enter an email.',
   email: 'Please enter a valid email.',
   passwordRequired: 'Please enter a password.',
-  invalidCredentials: 'Invalid credentials.',
-  guestAccountExists: 'Guest account exists.'
+  invalidCredentials: 'Invalid credentials.'
 }
 
-export const signInSchema = (
-  queryContext: QueryContextType,
-  queryClient: QueryClient
-) =>
+export const signInSchema = () =>
   z.object({
     email: z
-      .string({
-        required_error: messages.emailRequired
-      })
-      .email(messages.email)
-      .superRefine(async (email, ctx) => {
-        const { isGuest } = await queryClient.fetchQuery({
-          queryKey: [QUERY_KEYS.emailInUse, email],
-          queryFn: async () => await fetchEmailInUse(email, queryContext)
-        })
-        if (isGuest) {
-          ctx.addIssue({
-            code: z.ZodIssueCode.custom,
-            message: messages.guestAccountExists
-          })
-          return true
-        }
-        return z.NEVER // The return value is not used, but we need to return something to satisfy the typing
-      }),
+      .string({ required_error: messages.emailRequired })
+      .email(messages.email),
     password: z.string({
       required_error: messages.passwordRequired
     })

diff --git a/packages/common/src/services/auth/identity.ts b/packages/common/src/services/auth/identity.ts
@@ -201,19 +201,6 @@ export class IdentityService {
     })
   }
 
-  /**
-   * Check if an email address has been previously registered.
-   */
-  async checkIfEmailRegistered(email: string) {
-    return await this._makeRequest<{ exists: boolean; isGuest: boolean }>({
-      url: '/users/check',
-      method: 'get',
-      params: {
-        email
-      }
-    })
-  }
-
   /**
    * Get the user's email used for notifications and display.
    */

diff --git a/packages/identity-service/src/routes/user.js b/packages/identity-service/src/routes/user.js
@@ -123,33 +123,6 @@ module.exports = function (app) {
     })
   )
 
-  /**
-   * Check if a email address is taken. email is passed in via query param
-   */
-  app.get(
-    '/users/check',
-    handleResponse(async (req, res, next) => {
-      let email = req.query.email
-      if (email) {
-        email = email.toLowerCase()
-        const existingUser = await models.User.findOne({
-          where: {
-            email
-          }
-        })
-        if (existingUser) {
-          return successResponse({
-            exists: true,
-            isGuest: existingUser.isGuest
-          })
-        } else {
-          return successResponse({ exists: false })
-        }
-      } else
-        return errorResponseBadRequest('Please pass in a valid email address')
-    })
-  )
-
   /**
    * Update User Timezone / IP
    */

diff --git a/packages/identity-service/test/expressAppTest.js b/packages/identity-service/test/expressAppTest.js
@@ -49,4 +49,8 @@ describe('test /health_check and /balance_check', function () {
     await request(app).post('/wormhole_relay').send({}).expect(404)
     await request(app).get('/sol_balance_check').expect(404)
   })
+
+  it('does not expose email registration checks', async function () {
+    await request(app).get('/users/check?email=test@example.com').expect(404)
+  })
 })
diff --git a/packages/libs/src/api/Account.ts b/packages/libs/src/api/Account.ts
@@ -31,7 +31,6 @@ export class Account extends Base {
     this.confirmCredentials = this.confirmCredentials.bind(this)
     this.changeCredentials = this.changeCredentials.bind(this)
     this.resetPassword = this.resetPassword.bind(this)
-    this.checkIfEmailRegistered = this.checkIfEmailRegistered.bind(this)
     this.associateTwitterUser = this.associateTwitterUser.bind(this)
     this.associateInstagramUser = this.associateInstagramUser.bind(this)
     this.associateTikTokUser = this.associateTikTokUser.bind(this)
@@ -281,14 +280,6 @@ export class Account extends Base {
     return await this.hedgehog.confirmCredentials(args)
   }
 
-  /**
-   * Check if an email address has been previously registered.
-   */
-  async checkIfEmailRegistered(email: string) {
-    this.REQUIRES(Services.IDENTITY_SERVICE)
-    return await this.identityService.checkIfEmailRegistered(email)
-  }
-
   /**
    * Associates a user with a twitter uuid.
    * @param uuid from the Twitter API

diff --git a/packages/libs/src/services/identity/IdentityService.ts b/packages/libs/src/services/identity/IdentityService.ts
@@ -170,19 +170,6 @@ export class IdentityService {
     })
   }
 
-  /**
-   * Check if an email address has been previously registered.
-   */
-  async checkIfEmailRegistered(email: string) {
-    return await this._makeRequest<{ exists: boolean }>({
-      url: '/users/check',
-      method: 'get',
-      params: {
-        email
-      }
-    })
-  }
-
   /**
    * Check if the lookupKey exists.
    * WARNING: might not be the auth credentials for the current user!