diff --git a/keyserver/src/responders/link-responders.js b/keyserver/src/responders/link-responders.js
index 0673ad463..c43f6feaf 100644
--- a/keyserver/src/responders/link-responders.js
+++ b/keyserver/src/responders/link-responders.js
@@ -1,119 +1,119 @@
 // @flow
 
 import t, { type TUnion, type TInterface } from 'tcomb';
 
 import {
   type InviteLinkVerificationRequest,
   type InviteLinkVerificationResponse,
   type FetchInviteLinksResponse,
   type InviteLink,
   inviteLinkValidator,
   type CreateOrUpdatePublicLinkRequest,
 } from 'lib/types/link-types.js';
 import { tShape, tID } from 'lib/utils/validation-utils.js';
 
 import { createOrUpdatePublicLink } from '../creators/invite-link-creator.js';
 import { deleteInviteLink } from '../deleters/link-deleters.js';
 import {
   fetchPrimaryInviteLinks,
   verifyInviteLink,
 } from '../fetchers/link-fetchers.js';
 import { Viewer } from '../session/viewer.js';
 import { validateInput, validateOutput } from '../utils/validation-utils.js';
 
 const inviteLinkVerificationRequestInputValidator: TInterface<InviteLinkVerificationRequest> =
   tShape({
     secret: t.String,
   });
 
 export const inviteLinkVerificationResponseValidator: TUnion<InviteLinkVerificationResponse> =
   t.union([
     tShape({
       status: t.enums.of(['valid', 'already_joined']),
       community: tShape({
         name: t.String,
         id: tID,
       }),
     }),
     tShape({
       status: t.enums.of(['invalid', 'expired']),
     }),
   ]);
 
 async function inviteLinkVerificationResponder(
   viewer: Viewer,
-  input: any,
+  input: mixed,
 ): Promise<InviteLinkVerificationResponse> {
   const request = await validateInput(
     viewer,
     inviteLinkVerificationRequestInputValidator,
     input,
   );
   const response = await verifyInviteLink(viewer, request);
   return validateOutput(
     viewer.platformDetails,
     inviteLinkVerificationResponseValidator,
     response,
   );
 }
 
 export const fetchInviteLinksResponseValidator: TInterface<FetchInviteLinksResponse> =
   tShape<FetchInviteLinksResponse>({
     links: t.list(inviteLinkValidator),
   });
 
 async function fetchPrimaryInviteLinksResponder(
   viewer: Viewer,
 ): Promise<FetchInviteLinksResponse> {
   const primaryLinks = await fetchPrimaryInviteLinks(viewer);
   return validateOutput(
     viewer.platformDetails,
     fetchInviteLinksResponseValidator,
     {
       links: primaryLinks,
     },
   );
 }
 
 const createOrUpdatePublicLinkInputValidator: TInterface<CreateOrUpdatePublicLinkRequest> =
   tShape({
     name: t.String,
     communityID: tID,
   });
 
 async function createOrUpdatePublicLinkResponder(
   viewer: Viewer,
   input: mixed,
 ): Promise<InviteLink> {
   const request = await validateInput(
     viewer,
     createOrUpdatePublicLinkInputValidator,
     input,
   );
   const response = await createOrUpdatePublicLink(viewer, request);
   return validateOutput(viewer.platformDetails, inviteLinkValidator, response);
 }
 
 const disableInviteLinkInputValidator = tShape({
   name: t.String,
   communityID: tID,
 });
 
 async function disableInviteLinkResponder(
   viewer: Viewer,
   input: mixed,
 ): Promise<void> {
   const request = await validateInput(
     viewer,
     disableInviteLinkInputValidator,
     input,
   );
   await deleteInviteLink(viewer, request);
 }
 
 export {
   inviteLinkVerificationResponder,
   fetchPrimaryInviteLinksResponder,
   createOrUpdatePublicLinkResponder,
   disableInviteLinkResponder,
 };