diff --git a/backend/package.json b/backend/package.json
index 2c73629..9cfb2c1 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -18,11 +18,13 @@
     "directory": "backend"
   },
   "dependencies": {
+    "@hapi/joi": "15",
     "@pgtyped/cli": "^0.7.3",
     "@pgtyped/query": "^0.7.3",
     "@types/cors": "^2.8.6",
     "@types/express": "^4.17.1",
     "@types/express-session": "^1.15.14",
+    "@types/hapi__joi": "15",
     "@types/helmet": "^0.0.44",
     "@types/morgan": "^1.7.37",
     "@types/permit": "^0.2.1",
@@ -37,11 +39,13 @@
     "cors": "^2.8.5",
     "eslint": "^6.4.0",
     "express": "^4.17.0",
+    "express-joi-validation": "^4.0.4-beta.0",
     "express-promise-router": "^3.0.3",
     "express-session": "^1.16.2",
     "express-static-gzip": "^2.0.5",
     "express-validator": "^6.6.0",
     "helmet": "^3.21.1",
+    "joi-extract-type": "^15.0.8",
     "morgan": "^1.9.1",
     "pg": "^7.12.1",
     "redis": "^2.8.0",
diff --git a/backend/src/routes/auth.ts b/backend/src/routes/auth.ts
index f65b081..b66d883 100644
--- a/backend/src/routes/auth.ts
+++ b/backend/src/routes/auth.ts
@@ -1,10 +1,13 @@
 import Router from 'express-promise-router'
 import Container from 'typedi'
 import AuthService from '../services/AuthService'
-import validate from '../middleware/validate'
 import { NewUser } from 'auth'
+import { ContainerTypes, ValidatedRequest, ValidatedRequestSchema, createValidator } from 'express-joi-validation'
+import * as Joi from '@hapi/joi'
+import 'joi-extract-type'
 
 const router = Router()
+const validator = createValidator()
 const authService = Container.get(AuthService)
 
 router.post('/startLogin', async function (req, res) {
@@ -22,12 +25,27 @@ router.get('/startSignup', async function (req, res) {
     return res.json(responseData)
 })
 
+export const useridQuery = Joi.object({
+    userid: Joi.number().integer().required()
+})
+
+const signupSchema = Joi.object({
+    displayName: Joi.string().required(),
+    verifier: Joi.string().hex().required(),
+    srpSalt: Joi.string().hex().required(),
+    mukSalt: Joi.string().hex().required(),
+    publicKey: Joi.object().required(),
+    privateKey: Joi.string().base64().required(),
+    privateKeyIv: Joi.string().base64().required(),
+})
+
+interface SignupRequest extends ValidatedRequestSchema {
+    [ContainerTypes.Body]: Joi.extractType<typeof signupSchema>
+}
+
 router.post('/finishSignup',
-    validate({
-        privateKey: { in: ['body'], isBase64: true, },
-        privateKeyIv: { in: ['body'], isBase64: true, },
-    }),
-    async function (req, res) {
+    validator.body(signupSchema),
+    async function (req: ValidatedRequest<SignupRequest>, res) {
         const newUser : NewUser = {
             username: req.session.signupInfo.username,
             display_name: req.body.displayName,
diff --git a/backend/yarn.lock b/backend/yarn.lock
index ffed066..63cb5d2 100644
--- a/backend/yarn.lock
+++ b/backend/yarn.lock
@@ -23,6 +23,38 @@
     chalk "^2.0.0"
     js-tokens "^4.0.0"
 
+"@hapi/address@2.x.x":
+  version "2.1.4"
+  resolved "https://registry.yarnpkg.com/@hapi/address/-/address-2.1.4.tgz#5d67ed43f3fd41a69d4b9ff7b56e7c0d1d0a81e5"
+  integrity sha512-QD1PhQk+s31P1ixsX0H0Suoupp3VMXzIVMSwobR3F3MSUO2YCV0B7xqLcUw/Bh8yuvd3LhpyqLQWTNcRmp6IdQ==
+
+"@hapi/bourne@1.x.x":
+  version "1.3.2"
+  resolved "https://registry.yarnpkg.com/@hapi/bourne/-/bourne-1.3.2.tgz#0a7095adea067243ce3283e1b56b8a8f453b242a"
+  integrity sha512-1dVNHT76Uu5N3eJNTYcvxee+jzX4Z9lfciqRRHCU27ihbUcYi+iSc2iml5Ke1LXe1SyJCLA0+14Jh4tXJgOppA==
+
+"@hapi/hoek@8.x.x", "@hapi/hoek@^8.3.0":
+  version "8.5.1"
+  resolved "https://registry.yarnpkg.com/@hapi/hoek/-/hoek-8.5.1.tgz#fde96064ca446dec8c55a8c2f130957b070c6e06"
+  integrity sha512-yN7kbciD87WzLGc5539Tn0sApjyiGHAJgKvG9W8C7O+6c7qmoQMfVs0W4bX17eqz6C78QJqqFrtgdK5EWf6Qow==
+
+"@hapi/joi@15", "@hapi/joi@~15":
+  version "15.1.1"
+  resolved "https://registry.yarnpkg.com/@hapi/joi/-/joi-15.1.1.tgz#c675b8a71296f02833f8d6d243b34c57b8ce19d7"
+  integrity sha512-entf8ZMOK8sc+8YfeOlM8pCfg3b5+WZIKBfUaaJT8UsjAAPjartzxIYm3TIbjvA4u+u++KbcXD38k682nVHDAQ==
+  dependencies:
+    "@hapi/address" "2.x.x"
+    "@hapi/bourne" "1.x.x"
+    "@hapi/hoek" "8.x.x"
+    "@hapi/topo" "3.x.x"
+
+"@hapi/topo@3.x.x":
+  version "3.1.6"
+  resolved "https://registry.yarnpkg.com/@hapi/topo/-/topo-3.1.6.tgz#68d935fa3eae7fdd5ab0d7f953f3205d8b2bfc29"
+  integrity sha512-tAag0jEcjwH+P2quUfipd7liWCNX2F8NvYjQp2wtInsZxnMlypdw0FtAOLxtvvkO+GSRRbmNi8m/5y42PQJYCQ==
+  dependencies:
+    "@hapi/hoek" "^8.3.0"
+
 "@pgtyped/cli@^0.7.3":
   version "0.7.3"
   resolved "https://registry.yarnpkg.com/@pgtyped/cli/-/cli-0.7.3.tgz#2920182556a1225fe3f7f838aeb586d04aa72bc6"
@@ -132,6 +164,18 @@
     "@types/qs" "*"
     "@types/serve-static" "*"
 
+"@types/hapi__joi@*":
+  version "17.1.4"
+  resolved "https://registry.yarnpkg.com/@types/hapi__joi/-/hapi__joi-17.1.4.tgz#e46cd1bd81d25cd45247d652dadb3666514d807c"
+  integrity sha512-gqY3TeTyZvnyNhM02HgyCIoGIWsTFMnuzMfnD8evTsr1KIfueGJaz+QC77j+dFvhZ5cJArUNjDRHUjPxNohzGA==
+
+"@types/hapi__joi@15", "@types/hapi__joi@~15":
+  version "15.0.4"
+  resolved "https://registry.yarnpkg.com/@types/hapi__joi/-/hapi__joi-15.0.4.tgz#49e2e1e6da15ade0fdd6db4daf94aecb07bb391b"
+  integrity sha512-VSS6zc7AIOdHVXmqKaGNPYl8eGrMvWi0R5pt3evJL3UdxO8XS28/XAkBXNyLQoymHxhMd4bF3o1U9mZkWDeN8w==
+  dependencies:
+    "@types/hapi__joi" "*"
+
 "@types/helmet@^0.0.44":
   version "0.0.44"
   resolved "https://registry.yarnpkg.com/@types/helmet/-/helmet-0.0.44.tgz#cbded9530a7c4d8a9163fc7e017f0892acd1bb81"
@@ -980,6 +1024,11 @@ expect-ct@0.2.0:
   resolved "https://registry.yarnpkg.com/expect-ct/-/expect-ct-0.2.0.tgz#3a54741b6ed34cc7a93305c605f63cd268a54a62"
   integrity sha512-6SK3MG/Bbhm8MsgyJAylg+ucIOU71/FzyFalcfu5nY19dH8y/z0tBJU0wrNBXD4B27EoQtqPF/9wqH0iYAd04g==
 
+express-joi-validation@^4.0.4-beta.0:
+  version "4.0.4-beta.0"
+  resolved "https://registry.yarnpkg.com/express-joi-validation/-/express-joi-validation-4.0.4-beta.0.tgz#bb184d1daf01de5748d2ba0f397d44998a832fb8"
+  integrity sha512-1ozfZQkMKUHNchRQJIR5qzW2T6ENxJ8wSjDchVILHp+4fbLmJZIJkBfA27ZtZMTgRPEzg8vVU/cYdHM5DCSXEQ==
+
 express-promise-router@^3.0.3:
   version "3.0.3"
   resolved "https://registry.yarnpkg.com/express-promise-router/-/express-promise-router-3.0.3.tgz#5e6d22a5a3f013d71833172fe8d7ab780c3f6b70"
@@ -1482,6 +1531,14 @@ jmespath@0.15.0:
   resolved "https://registry.yarnpkg.com/jmespath/-/jmespath-0.15.0.tgz#a3f222a9aae9f966f5d27c796510e28091764217"
   integrity sha1-o/Iiqarp+Wb10nx5ZRDigJF2Qhc=
 
+joi-extract-type@^15.0.8:
+  version "15.0.8"
+  resolved "https://registry.yarnpkg.com/joi-extract-type/-/joi-extract-type-15.0.8.tgz#29b42d79717b8fec6841b2bef76f97542e58e687"
+  integrity sha512-Or97aW6QN6YJq0B+x/vYs65+nmcPvYDE7xhlwRl7yHzY+7Z8pVaj0zxjdJlXmIA9zRcbbYQKCGvW+I4g0kUHgA==
+  dependencies:
+    "@hapi/joi" "~15"
+    "@types/hapi__joi" "~15"
+
 js-tokens@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-4.0.0.tgz#19203fb59991df98e3a287050d4647cdeaf32499"