diff --git a/lib/letter-avatars.js b/lib/letter-avatars.ts
similarity index 75%
rename from lib/letter-avatars.js
rename to lib/letter-avatars.ts
index 6fb1888ab..f5c27a9d5 100644
--- a/lib/letter-avatars.js
+++ b/lib/letter-avatars.ts
@@ -1,12 +1,11 @@
 'use strict'
-// external modules
-const crypto = require('crypto')
-const randomcolor = require('randomcolor')
-const config = require('./config')
+import { createHash } from 'crypto'
+import randomColor from 'randomcolor'
+import config from './config'
 
 // core
-exports.generateAvatar = function (name) {
-  const color = randomcolor({
+export function generateAvatar (name: string): string {
+  const color = randomColor({
     seed: name,
     luminosity: 'dark'
   })
@@ -25,16 +24,16 @@ exports.generateAvatar = function (name) {
   return svg
 }
 
-exports.generateAvatarURL = function (name, email = '', big = true) {
+export function generateAvatarURL (name: string, email = '', big = true): string {
   let photo
-  if (typeof email !== 'string') {
+  if (email.length === 0) {
     email = '' + name + '@example.com'
   }
   name = encodeURIComponent(name)
 
-  let hash = crypto.createHash('md5')
+  const hash = createHash('md5')
   hash.update(email.toLowerCase())
-  let hexDigest = hash.digest('hex')
+  const hexDigest = hash.digest('hex')
 
   if (email !== '' && config.allowGravatar) {
     photo = 'https://cdn.libravatar.org/avatar/' + hexDigest
diff --git a/package.json b/package.json
index 98ca7287b..79bcbfcff 100644
--- a/package.json
+++ b/package.json
@@ -17,6 +17,7 @@
   },
   "dependencies": {
     "@passport-next/passport-openid": "^1.0.0",
+    "@types/randomcolor": "^0.5.4",
     "Idle.Js": "git+https://github.com/shawnmclean/Idle.js",
     "archiver": "^2.1.1",
     "async": "^2.1.4",
diff --git a/yarn.lock b/yarn.lock
index e0c3cfff7..6f0c3f5c3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -202,6 +202,11 @@
   resolved "https://registry.yarnpkg.com/@types/qs/-/qs-6.9.1.tgz#937fab3194766256ee09fcd40b781740758617e7"
   integrity sha512-lhbQXx9HKZAPgBkISrBcmAcMpZsmpe/Cd/hY7LGZS5OfkySUBItnPZHgQPssWYUET8elF+yCFBbP1Q0RZPTdaw==
 
+"@types/randomcolor@^0.5.4":
+  version "0.5.4"
+  resolved "https://registry.yarnpkg.com/@types/randomcolor/-/randomcolor-0.5.4.tgz#75230e780326bf372c13015c361dddca1087eb0f"
+  integrity sha512-7pIw2aYtWXEiqfP01L1+b+Xk3mGGKA14yW492CfaR0lliSM4W6PGB/uhjQX08kFMEK8sAOrT3ufiKUnLlG0ulw==
+
 "@types/range-parser@*":
   version "1.2.3"
   resolved "https://registry.yarnpkg.com/@types/range-parser/-/range-parser-1.2.3.tgz#7ee330ba7caafb98090bece86a5ee44115904c2c"