diff --git a/packages/builder/.gitignore b/packages/builder/.gitignore
index e5c961d509..41411ea16c 100644
--- a/packages/builder/.gitignore
+++ b/packages/builder/.gitignore
@@ -5,4 +5,5 @@ package-lock.json
 release/
 dist/
 routify
-.routify/
\ No newline at end of file
+.routify/
+.rollup.cache
\ No newline at end of file
diff --git a/packages/builder/package.json b/packages/builder/package.json
index fd819b8a9c..c98e817486 100644
--- a/packages/builder/package.json
+++ b/packages/builder/package.json
@@ -4,14 +4,14 @@
   "license": "GPL-3.0",
   "private": true,
   "scripts": {
-    "svelte-check": "svelte-check --no-tsconfig",
-    "build": "yarn svelte-check && routify -b && vite build --emptyOutDir",
+    "build": "routify -b && NODE_OPTIONS=\"--max_old_space_size=4096\" vite build --emptyOutDir",
     "start": "routify -c rollup",
     "dev": "routify -c dev:vite",
     "dev:vite": "vite --host 0.0.0.0",
     "rollup": "rollup -c -w",
     "test": "vitest run",
-    "test:watch": "vitest"
+    "test:watch": "vitest",
+    "check:types": "yarn svelte-check"
   },
   "jest": {
     "globals": {
@@ -89,6 +89,7 @@
     "@babel/plugin-transform-runtime": "^7.13.10",
     "@babel/preset-env": "^7.13.12",
     "@rollup/plugin-replace": "^5.0.3",
+    "@rollup/plugin-typescript": "8.3.0",
     "@roxi/routify": "2.18.12",
     "@sveltejs/vite-plugin-svelte": "1.4.0",
     "@testing-library/jest-dom": "6.4.2",
diff --git a/packages/builder/src/api.js b/packages/builder/src/api.ts
similarity index 87%
rename from packages/builder/src/api.js
rename to packages/builder/src/api.ts
index 6441b4ff48..5d1a0beaeb 100644
--- a/packages/builder/src/api.js
+++ b/packages/builder/src/api.ts
@@ -8,7 +8,7 @@ import { get } from "svelte/store"
 import { auth, navigation } from "./stores/portal"
 
 export const API = createAPIClient({
-  attachHeaders: headers => {
+  attachHeaders: (headers: Record<string, string>) => {
     // Attach app ID header from store
     let appId = get(appStore).appId
     if (appId) {
@@ -16,13 +16,13 @@ export const API = createAPIClient({
     }
 
     // Add csrf token if authenticated
-    const user = get(auth).user
+    const user: any = get(auth).user
     if (user?.csrfToken) {
       headers["x-csrf-token"] = user.csrfToken
     }
   },
 
-  onError: error => {
+  onError: (error: any) => {
     const { url, message, status, method, handled } = error || {}
 
     // Log any errors that we haven't manually handled
@@ -45,14 +45,14 @@ export const API = createAPIClient({
       }
     }
   },
-  onMigrationDetected: appId => {
+  onMigrationDetected: (appId: string) => {
     const updatingUrl = `/builder/app/updating/${appId}`
 
     if (window.location.pathname === updatingUrl) {
       return
     }
 
-    get(navigation).goto(
+    get(navigation)?.goto(
       `${updatingUrl}?returnUrl=${encodeURIComponent(window.location.pathname)}`
     )
   },
diff --git a/packages/builder/src/index.d.ts b/packages/builder/src/index.d.ts
new file mode 100644
index 0000000000..1cbad4f12c
--- /dev/null
+++ b/packages/builder/src/index.d.ts
@@ -0,0 +1,8 @@
+declare module "api" {
+  const API: {
+    getPlugins: () => Promise<any>
+    createPlugin: (plugin: object) => Promise<any>
+    uploadPlugin: (plugin: FormData) => Promise<any>
+    deletePlugin: (id: string) => Promise<void>
+  }
+}
diff --git a/packages/builder/src/stores/portal/navigation.js b/packages/builder/src/stores/portal/navigation.ts
similarity index 69%
rename from packages/builder/src/stores/portal/navigation.js
rename to packages/builder/src/stores/portal/navigation.ts
index 67a06eff53..2b230622f6 100644
--- a/packages/builder/src/stores/portal/navigation.js
+++ b/packages/builder/src/stores/portal/navigation.ts
@@ -1,13 +1,20 @@
 import { writable } from "svelte/store"
 
+type GotoFuncType = (path: string) => void
+
+interface Store {
+  initialisated: boolean
+  goto: GotoFuncType
+}
+
 export function createNavigationStore() {
-  const store = writable({
+  const store = writable<Store>({
     initialisated: false,
-    goto: undefined,
+    goto: undefined as any,
   })
   const { set, subscribe } = store
 
-  const init = gotoFunc => {
+  const init = (gotoFunc: GotoFuncType) => {
     if (typeof gotoFunc !== "function") {
       throw new Error(
         `gotoFunc must be a function, found a "${typeof gotoFunc}" instead`
diff --git a/packages/builder/src/stores/portal/plugins.js b/packages/builder/src/stores/portal/plugins.ts
similarity index 81%
rename from packages/builder/src/stores/portal/plugins.js
rename to packages/builder/src/stores/portal/plugins.ts
index e259f9aa6d..15110a852b 100644
--- a/packages/builder/src/stores/portal/plugins.js
+++ b/packages/builder/src/stores/portal/plugins.ts
@@ -1,16 +1,21 @@
 import { writable } from "svelte/store"
+import { PluginSource } from "constants/index"
+
 import { API } from "api"
-import { PluginSource } from "constants"
+
+interface Plugin {
+  _id: string
+}
 
 export function createPluginsStore() {
-  const { subscribe, set, update } = writable([])
+  const { subscribe, set, update } = writable<Plugin[]>([])
 
   async function load() {
     const plugins = await API.getPlugins()
     set(plugins)
   }
 
-  async function deletePlugin(pluginId) {
+  async function deletePlugin(pluginId: string) {
     await API.deletePlugin(pluginId)
     update(state => {
       state = state.filter(existing => existing._id !== pluginId)
@@ -18,8 +23,8 @@ export function createPluginsStore() {
     })
   }
 
-  async function createPlugin(source, url, auth = null) {
-    let pluginData = {
+  async function createPlugin(source: string, url: string, auth = null) {
+    let pluginData: any = {
       source,
       url,
     }
@@ -46,7 +51,7 @@ export function createPluginsStore() {
     })
   }
 
-  async function uploadPlugin(file) {
+  async function uploadPlugin(file: File) {
     if (!file) {
       return
     }
diff --git a/packages/builder/tsconfig.build.json b/packages/builder/tsconfig.build.json
index 6a5ba315a1..ca1316f83c 100644
--- a/packages/builder/tsconfig.build.json
+++ b/packages/builder/tsconfig.build.json
@@ -9,15 +9,9 @@
     "noImplicitAny": true,
     "esModuleInterop": true,
     "resolveJsonModule": true,
-    "incremental": true
+    "incremental": true,
+    "skipLibCheck": true
   },
-  "include": [
-    "./src/**/*"
-  ],
-  "exclude": [
-    "node_modules",
-    "**/*.json",
-    "**/*.spec.ts",
-    "**/*.spec.js"
-  ]
+  "include": ["./src/**/*"],
+  "exclude": ["node_modules", "**/*.json", "**/*.spec.ts", "**/*.spec.js"]
 }
diff --git a/packages/builder/vite.config.mjs b/packages/builder/vite.config.mjs
index f5ff388952..ccc5729d28 100644
--- a/packages/builder/vite.config.mjs
+++ b/packages/builder/vite.config.mjs
@@ -3,6 +3,7 @@ import replace from "@rollup/plugin-replace"
 import { defineConfig, loadEnv } from "vite"
 import { viteStaticCopy } from "vite-plugin-static-copy"
 import path from "path"
+import typescript from "@rollup/plugin-typescript"
 
 const ignoredWarnings = [
   "unused-export-let",
@@ -35,7 +36,7 @@ export default defineConfig(({ mode }) => {
     // Copy fonts to an additional path so that svelte's automatic
     // prefixing of the base URL path can still resolve assets
     copyFonts("builder/fonts"),
-]
+  ]
 
   return {
     test: {
@@ -61,6 +62,7 @@ export default defineConfig(({ mode }) => {
       sourcemap: !isProduction,
     },
     plugins: [
+      typescript({ outDir: "../server/builder/dist" }),
       svelte({
         hot: !isProduction,
         emitCss: true,