diff --git a/package.json b/package.json
index 4c2350f..1e21545 100644
--- a/package.json
+++ b/package.json
@@ -43,6 +43,7 @@
     "ramda": "^0.25.0"
   },
   "devDependencies": {
+    "@types/express": "^4.16.0",
     "@types/jest": "^23.1.3",
     "@types/node": "^10.5.1",
     "conventional-changelog-cli": "^2.0.0",
diff --git a/src/alice.ts b/src/alice.ts
index cc4e437..15ee3e3 100644
--- a/src/alice.ts
+++ b/src/alice.ts
@@ -15,10 +15,10 @@ import {
 import {
   applyMiddlewares,
   MiddlewareType,
-
-  createAliceStateMiddleware,
 } from './middlewares'
 
+import aliceStateMiddleware from './middlewares/aliceStateMiddleware'
+
 const DEFAULT_SESSIONS_LIMIT: number = 1000
 
 export default class Alice {
@@ -36,7 +36,7 @@ export default class Alice {
     this.anyCallback = null
     this.welcomeCallback = null
     this.commands = new Commands(config.fuseOptions || null)
-    this.middlewares = [createAliceStateMiddleware()]
+    this.middlewares = [aliceStateMiddleware()]
     this.scenes = []
     this.currentScene = null
     this.sessions = new Sessions()
diff --git a/src/button.ts b/src/button.ts
index 43ea543..6365c5c 100644
--- a/src/button.ts
+++ b/src/button.ts
@@ -1,4 +1,12 @@
-const button = (params) => {
+export interface ButtonParams {
+  title: string,
+  text: string,
+  tts?: string,
+  url?: string,
+  hide?: boolean,
+  payload?: {}
+}
+const button = (params: ButtonParams) => {
   // Button has been created from string
   if (typeof params === 'string') {
     return {
diff --git a/src/commands.ts b/src/commands.ts
index fa23e2e..85a32fb 100644
--- a/src/commands.ts
+++ b/src/commands.ts
@@ -8,7 +8,7 @@ const TYPE_FIGURE = 'figure'
 const TYPE_REGEXP = 'regexp'
 const TYPE_ARRAY = 'array'
 
-class Commands {
+export default class Commands {
   public commands: Command[]
   public fuseOptions: {}
   constructor(config = null) {
@@ -93,5 +93,4 @@ class Commands {
 module.exports = Commands
 module.exports.Command = Command
 
-export default Commands
 export { Command }
diff --git a/src/middlewares.ts b/src/middlewares.ts
index 9348024..f02739f 100644
--- a/src/middlewares.ts
+++ b/src/middlewares.ts
@@ -21,21 +21,3 @@ export async function applyMiddlewares(middlewares, ctx: Ctx): Promise<Ctx> {
   }
   return newContext
 }
-
-export function createAliceStateMiddleware() {
-  const store = new Map()
-
-  return async (ctx) => {
-    const key = ctx.session.sessionId
-    let { state } = store.get(key) || { state: {} }
-    Object.defineProperty(ctx, 'state', {
-      get() { return state },
-      set(value) { state = Object.assign({}, value) },
-    })
-    store.set(key, {
-      state,
-    })
-
-    return ctx
-  }
-}
diff --git a/src/middlewares/aliceStateMiddleware.ts b/src/middlewares/aliceStateMiddleware.ts
new file mode 100644
index 0000000..05a99a0
--- /dev/null
+++ b/src/middlewares/aliceStateMiddleware.ts
@@ -0,0 +1,17 @@
+export default function aliceStateMiddleware() {
+  const store = new Map()
+
+  return async (ctx) => {
+    const key = ctx.session.sessionId
+    let { state } = store.get(key) || { state: {} }
+    Object.defineProperty(ctx, 'state', {
+      get() { return state },
+      set(value) { state = Object.assign({}, value) },
+    })
+    store.set(key, {
+      state,
+    })
+
+    return ctx
+  }
+}
diff --git a/src/reply.ts b/src/reply.ts
index f5ff1e7..278b840 100644
--- a/src/reply.ts
+++ b/src/reply.ts
@@ -2,17 +2,37 @@
 
 const {
   DEFAULT_END_SESSION,
-  ALICE_PROTOCOL_VERSION
+  ALICE_PROTOCOL_VERSION,
 } = require('./constants')
+import { ButtonParams } from './button'
 
-const reply = (params) => {
-  const data = {
+interface ReplyType {
+  response: {
+    text: string,
+    buttons?: ButtonParams[],
+    end_session: boolean,
+  },
+  session?: {},
+  version: string,
+}
+
+interface ParamsType {
+  text: string,
+  tts?: string,
+  shouldEndSession?: boolean,
+  endSession?: boolean,
+  end_session?: boolean,
+  session: {},
+  buttons: any[]
+}
+const reply = (params: ParamsType) => {
+  const data: ReplyType = {
     response: {
       buttons: [],
-      end_session: DEFAULT_END_SESSION
+      end_session: DEFAULT_END_SESSION,
     },
     session: null,
-    version: ALICE_PROTOCOL_VERSION
+    version: ALICE_PROTOCOL_VERSION,
   }
 
   if (typeof params === 'string') {
@@ -26,16 +46,16 @@ const reply = (params) => {
       endSession,
       end_session,
       session,
-      buttons
+      buttons,
     } = params
 
-    if (text) data.response.text = text
-    if (tts) data.response.tts = tts
-    if (buttons) data.response.buttons = buttons
+    if (text) { data.response.text = text }
+    if (tts) { data.response.tts = tts }
+    if (buttons) { data.response.buttons = buttons }
     if (shouldEndSession || end_session || endSession) {
       data.response.end_session = shouldEndSession || end_session || endSession
     }
-    if (session) data.session = session
+    if (session) { data.session = session }
 
     return data
   } else {
diff --git a/src/scene.ts b/src/scene.ts
index 91673e7..9d59f5f 100644
--- a/src/scene.ts
+++ b/src/scene.ts
@@ -1,11 +1,18 @@
 import Alice from './alice'
-const Commands = require('./commands')
-const Command = require('./commands').Command
-const Ctx = require('./ctx')
+import Commands from './commands'
+import Command from './Command'
+import Ctx from './ctx'
 
 const selectCommand = (req) => req.request.command
 
 export default class Scene extends Alice {
+  public name: string
+  public enterCommand: Command
+  public leaveCommand: Command
+  public anyCallback: (ctx: Ctx) => void
+  public commands: Commands
+  public config: {}
+
   constructor(name, config = {}) {
     super()
     this.name = name
@@ -16,6 +23,7 @@ export default class Scene extends Alice {
     this.enterCommand = null
     this.leaveCommand = null
   }
+
   get title() {
     return this.name
   }
diff --git a/tsconfig.json b/tsconfig.json
index 3c1b58e..04a7bbd 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -14,7 +14,7 @@
                 "src/types/*"
             ]
         },
-        "types": ["node", "jest"],
+        "types": ["node", "jest", "express"],
         // typeRoots option has been previously configured
         "typeRoots": [
             // add path to @types