diff --git a/example/typescript/src/mastodon/proxy_streaming.ts b/example/typescript/src/mastodon/proxy_streaming.ts
index 824098694..d0f8eba1f 100644
--- a/example/typescript/src/mastodon/proxy_streaming.ts
+++ b/example/typescript/src/mastodon/proxy_streaming.ts
@@ -1,4 +1,4 @@
-import generator, { Entity, StreamListener, ProxyConfig } from 'megalodon'
+import generator, { Entity, StreamListenerInterface, ProxyConfig } from 'megalodon'
 
 declare var process: {
   env: {
@@ -21,7 +21,7 @@ const proxy: ProxyConfig = {
 
 const client = generator('mastodon', BASE_URL, access_token, null, proxy)
 
-const stream: StreamListener = client.userStream()
+const stream: StreamListenerInterface = client.userStream()
 stream.on('connect', _ => {
   console.log('connect')
 })
diff --git a/example/typescript/src/mastodon/streaming.ts b/example/typescript/src/mastodon/streaming.ts
index 98de217cd..b4c16719b 100644
--- a/example/typescript/src/mastodon/streaming.ts
+++ b/example/typescript/src/mastodon/streaming.ts
@@ -1,4 +1,4 @@
-import generator, { Entity, StreamListener } from 'megalodon'
+import generator, { Entity, StreamListenerInterface } from 'megalodon'
 
 declare var process: {
   env: {
@@ -12,7 +12,7 @@ const access_token: string = process.env.MASTODON_ACCESS_TOKEN
 
 const client = generator('mastodon', BASE_URL, access_token)
 
-const stream: StreamListener = client.publicStream()
+const stream: StreamListenerInterface = client.publicStream()
 stream.on('connect', _ => {
   console.log('connect')
 })
diff --git a/example/typescript/src/pleroma/proxy_web_socket.ts b/example/typescript/src/pleroma/proxy_web_socket.ts
index 759f20df7..9aabb0d6c 100644
--- a/example/typescript/src/pleroma/proxy_web_socket.ts
+++ b/example/typescript/src/pleroma/proxy_web_socket.ts
@@ -1,4 +1,4 @@
-import generator, { Entity, WebSocket, ProxyConfig } from 'megalodon'
+import generator, { Entity, WebSocketInterface, ProxyConfig } from 'megalodon'
 import log4js from 'log4js'
 
 declare var process: {
@@ -22,7 +22,7 @@ const proxy: ProxyConfig = {
 
 const client = generator('pleroma', BASE_URL, access_token, null, proxy)
 
-const stream: WebSocket = client.userSocket()
+const stream: WebSocketInterface = client.userSocket()
 
 const logger = log4js.getLogger()
 logger.level = 'debug'
diff --git a/example/typescript/src/pleroma/web_socket.ts b/example/typescript/src/pleroma/web_socket.ts
index 9cd25e262..4a54756a9 100644
--- a/example/typescript/src/pleroma/web_socket.ts
+++ b/example/typescript/src/pleroma/web_socket.ts
@@ -1,4 +1,4 @@
-import generator, { Entity, WebSocket } from 'megalodon'
+import generator, { Entity, WebSocketInterface } from 'megalodon'
 import log4js from 'log4js'
 
 declare var process: {
@@ -13,7 +13,7 @@ const access_token: string = process.env.PLEROMA_ACCESS_TOKEN
 
 const client = generator('pleroma', BASE_URL, access_token)
 
-const stream: WebSocket = client.userSocket()
+const stream: WebSocketInterface = client.userSocket()
 
 const logger = log4js.getLogger()
 logger.level = 'debug'
diff --git a/src/index.ts b/src/index.ts
index 30c8b9e77..e4e37114f 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,12 +1,10 @@
 import MastodonAPI from './mastodon/api_client'
-import StreamListener from './stream_listener'
-import WebSocket from './web_socket'
 import Response from './response'
 import OAuth from './oauth'
 import { isCancel, RequestCanceledError } from './cancel'
 import { ProxyConfig } from './proxy_config'
 //
-import generator, { MegalodonInterface } from './megalodon'
+import generator, { MegalodonInterface, WebSocketInterface, StreamListenerInterface } from './megalodon'
 import Mastodon from './mastodon'
 import Pleroma from './pleroma'
 import Misskey from './misskey'
@@ -14,8 +12,6 @@ import Entity from './entity'
 
 export {
   MastodonAPI,
-  StreamListener,
-  WebSocket,
   Response,
   OAuth,
   RequestCanceledError,
@@ -23,6 +19,8 @@ export {
   ProxyConfig,
   //
   MegalodonInterface,
+  WebSocketInterface,
+  StreamListenerInterface,
   Mastodon,
   Pleroma,
   Misskey,
diff --git a/src/mastodon.ts b/src/mastodon.ts
index 71df21a93..95d41080c 100644
--- a/src/mastodon.ts
+++ b/src/mastodon.ts
@@ -3,9 +3,8 @@ import MastodonAPI from './mastodon/api_client'
 import { ProxyConfig } from './proxy_config'
 import OAuth from './oauth'
 import Response from './response'
-import StreamListener from './stream_listener'
-import WebSocket from './web_socket'
-import { MegalodonInterface, NoImplementedError } from './megalodon'
+import WebSocket from './mastodon/web_socket'
+import { MegalodonInterface, StreamListenerInterface, NoImplementedError } from './megalodon'
 import Entity from './entity'
 import { NO_REDIRECT, DEFAULT_SCOPE, DEFAULT_UA } from './default'
 
@@ -1913,27 +1912,27 @@ export default class Mastodon implements MegalodonInterface {
   // ======================================
   // HTTP Streaming
   // ======================================
-  public userStream(): StreamListener {
+  public userStream(): StreamListenerInterface {
     return this.client.stream('/api/v1/streaming/user')
   }
 
-  public publicStream(): StreamListener {
+  public publicStream(): StreamListenerInterface {
     return this.client.stream('/api/v1/streaming/public')
   }
 
-  public localStream(): StreamListener {
+  public localStream(): StreamListenerInterface {
     return this.client.stream('/api/v1/streaming/public/local')
   }
 
-  public tagStream(tag: string): StreamListener {
+  public tagStream(tag: string): StreamListenerInterface {
     return this.client.stream(`/api/v1/streaming/hashtag?tag=${tag}`)
   }
 
-  public listStream(list_id: string): StreamListener {
+  public listStream(list_id: string): StreamListenerInterface {
     return this.client.stream(`/api/v1/streaming/list?list=${list_id}`)
   }
 
-  public directStream(): StreamListener {
+  public directStream(): StreamListenerInterface {
     return this.client.stream('/api/v1/streaming/direct')
   }
 
diff --git a/src/mastodon/api_client.ts b/src/mastodon/api_client.ts
index 31db72714..da1ea4d23 100644
--- a/src/mastodon/api_client.ts
+++ b/src/mastodon/api_client.ts
@@ -1,6 +1,6 @@
 import axios, { AxiosResponse, CancelTokenSource, AxiosRequestConfig } from 'axios'
-import StreamListener from '../stream_listener'
-import WebSocket from '../web_socket'
+import StreamListener from './stream_listener'
+import WebSocket from './web_socket'
 import Response from '../response'
 import { RequestCanceledError } from '../cancel'
 import proxyAgent, { ProxyConfig } from '../proxy_config'
diff --git a/src/stream_listener.ts b/src/mastodon/stream_listener.ts
similarity index 90%
rename from src/stream_listener.ts
rename to src/mastodon/stream_listener.ts
index 71d8579ce..731ff8583 100644
--- a/src/stream_listener.ts
+++ b/src/mastodon/stream_listener.ts
@@ -1,9 +1,11 @@
 import { EventEmitter } from 'events'
 import axios, { CancelTokenSource, AxiosRequestConfig } from 'axios'
 import httpAdapter from 'axios/lib/adapters/http'
-import { Parser } from './parser'
-import proxyAgent, { ProxyConfig } from './proxy_config'
+import { Parser } from '../parser'
+import proxyAgent, { ProxyConfig } from '../proxy_config'
 import Entity from './entity'
+import { StreamListenerInterface } from '../megalodon'
+import MastodonAPI from './api_client'
 
 const STATUS_CODES_TO_ABORT_ON: Array<number> = [400, 401, 403, 404, 406, 410, 422]
 
@@ -22,7 +24,7 @@ export class StreamListenerError extends Error {
  * EventStream
  * Listener of text/event-stream. It receives data, and parse when streaming.
  */
-export default class StreamListener extends EventEmitter {
+export default class StreamListener extends EventEmitter implements StreamListenerInterface {
   public url: string
   public headers: object
   public parser: Parser
@@ -161,13 +163,13 @@ export default class StreamListener extends EventEmitter {
    **/
   private _setupParser() {
     this.parser.on('update', (status: Entity.Status) => {
-      this.emit('update', status)
+      this.emit('update', MastodonAPI.Converter.status(status))
     })
     this.parser.on('notification', (notification: Entity.Notification) => {
-      this.emit('notification', notification)
+      this.emit('notification', MastodonAPI.Converter.notification(notification))
     })
     this.parser.on('conversation', (conversation: Entity.Conversation) => {
-      this.emit('conversation', conversation)
+      this.emit('conversation', MastodonAPI.Converter.conversation(conversation))
     })
     this.parser.on('delete', (id: string) => {
       this.emit('delete', id)
diff --git a/src/web_socket.ts b/src/mastodon/web_socket.ts
similarity index 94%
rename from src/web_socket.ts
rename to src/mastodon/web_socket.ts
index 10ceacad7..07c6f52c8 100644
--- a/src/web_socket.ts
+++ b/src/mastodon/web_socket.ts
@@ -1,15 +1,17 @@
 import WS from 'ws'
 import moment, { Moment } from 'moment'
 import { EventEmitter } from 'events'
-import proxyAgent, { ProxyConfig } from './proxy_config'
-import Entity from './entity'
+import proxyAgent, { ProxyConfig } from '../proxy_config'
+import Entity from '../entity'
+import { WebSocketInterface } from '../megalodon'
+import MastodonAPI from './api_client'
 
 /**
  * WebSocket
  * Pleroma is not support streaming. It is support websocket instead of streaming.
  * So this class connect to Phoenix websocket for Pleroma.
  */
-export default class WebSocket extends EventEmitter {
+export default class WebSocket extends EventEmitter implements WebSocketInterface {
   public url: string
   public stream: string
   public params: string | null
@@ -232,16 +234,16 @@ export default class WebSocket extends EventEmitter {
    */
   private _setupParser() {
     this.parser.on('update', (status: Entity.Status) => {
-      this.emit('update', status)
+      this.emit('update', MastodonAPI.Converter.status(status))
     })
     this.parser.on('notification', (notification: Entity.Notification) => {
-      this.emit('notification', notification)
+      this.emit('notification', MastodonAPI.Converter.notification(notification))
     })
     this.parser.on('delete', (id: string) => {
       this.emit('delete', id)
     })
     this.parser.on('conversation', (conversation: Entity.Conversation) => {
-      this.emit('conversation', conversation)
+      this.emit('conversation', MastodonAPI.Converter.conversation(conversation))
     })
     this.parser.on('error', (err: Error) => {
       this.emit('parser-error', err)
diff --git a/src/megalodon.ts b/src/megalodon.ts
index 52b24daf7..891f5c6f4 100644
--- a/src/megalodon.ts
+++ b/src/megalodon.ts
@@ -1,5 +1,3 @@
-import StreamListener from './stream_listener'
-import WebSocket from './web_socket'
 import Response from './response'
 import OAuth from './oauth'
 import Pleroma from './pleroma'
@@ -8,6 +6,26 @@ import Mastodon from './mastodon'
 import Entity from './entity'
 import axios, { AxiosRequestConfig, AxiosResponse } from 'axios'
 
+export interface WebSocketInterface {
+  start(): void
+  stop(): void
+  // EventEmitter
+  on(event: string | symbol, listener: (...args: any[]) => void): this
+  once(event: string | symbol, listener: (...args: any[]) => void): this
+  removeListener(event: string | symbol, listener: (...args: any[]) => void): this
+  removeAllListeners(event?: string | symbol): this
+}
+
+export interface StreamListenerInterface {
+  start(): void
+  stop(): void
+  // EventEmitter
+  on(event: string | symbol, listener: (...args: any[]) => void): this
+  once(event: string | symbol, listener: (...args: any[]) => void): this
+  removeListener(event: string | symbol, listener: (...args: any[]) => void): this
+  removeAllListeners(event?: string | symbol): this
+}
+
 export interface MegalodonInterface {
   /**
    * Cancel all requests in this instance.
@@ -1132,22 +1150,22 @@ export interface MegalodonInterface {
   // ======================================
   // HTTP Streaming
   // ======================================
-  userStream(): StreamListener
-  publicStream(): StreamListener
-  localStream(): StreamListener
-  tagStream(tag: string): StreamListener
-  listStream(list_id: string): StreamListener
-  directStream(): StreamListener
+  userStream(): StreamListenerInterface
+  publicStream(): StreamListenerInterface
+  localStream(): StreamListenerInterface
+  tagStream(tag: string): StreamListenerInterface
+  listStream(list_id: string): StreamListenerInterface
+  directStream(): StreamListenerInterface
 
   // ======================================
   // WebSocket
   // ======================================
-  userSocket(): WebSocket
-  publicSocket(): WebSocket
-  localSocket(): WebSocket
-  tagSocket(tag: string): WebSocket
-  listSocket(list_id: string): WebSocket
-  directSocket(): WebSocket
+  userSocket(): WebSocketInterface
+  publicSocket(): WebSocketInterface
+  localSocket(): WebSocketInterface
+  tagSocket(tag: string): WebSocketInterface
+  listSocket(list_id: string): WebSocketInterface
+  directSocket(): WebSocketInterface
 }
 
 export class NoImplementedError extends Error {
diff --git a/src/misskey.ts b/src/misskey.ts
index 3ee0ce0d8..835c5e325 100644
--- a/src/misskey.ts
+++ b/src/misskey.ts
@@ -3,9 +3,14 @@ import { DEFAULT_UA } from './default'
 import { ProxyConfig } from './proxy_config'
 import OAuth from './oauth'
 import Response from './response'
-import { MegalodonInterface, NoImplementedError, ArgumentError, UnexpectedError } from './megalodon'
-import StreamListener from './stream_listener'
-import WebSocket from './web_socket'
+import {
+  MegalodonInterface,
+  StreamListenerInterface,
+  WebSocketInterface,
+  NoImplementedError,
+  ArgumentError,
+  UnexpectedError
+} from './megalodon'
 
 export default class Misskey implements MegalodonInterface {
   public client: MisskeyAPI.Client
@@ -1830,51 +1835,51 @@ export default class Misskey implements MegalodonInterface {
   // ======================================
   // HTTP Streaming
   // ======================================
-  public userStream(): StreamListener {
+  public userStream(): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public publicStream(): StreamListener {
+  public publicStream(): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public localStream(): StreamListener {
+  public localStream(): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public tagStream(_tag: string): StreamListener {
+  public tagStream(_tag: string): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public listStream(_list_id: string): StreamListener {
+  public listStream(_list_id: string): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public directStream(): StreamListener {
+  public directStream(): StreamListenerInterface {
     throw new NoImplementedError('misskey does not support')
   }
 
-  public userSocket(): WebSocket {
+  public userSocket(): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 
-  public publicSocket(): WebSocket {
+  public publicSocket(): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 
-  public localSocket(): WebSocket {
+  public localSocket(): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 
-  public tagSocket(_tag: string): WebSocket {
+  public tagSocket(_tag: string): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 
-  public listSocket(_list_id: string): WebSocket {
+  public listSocket(_list_id: string): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 
-  public directSocket(): WebSocket {
+  public directSocket(): WebSocketInterface {
     throw new NoImplementedError('TODO: implement')
   }
 }
diff --git a/src/pleroma.ts b/src/pleroma.ts
index 8d2833a9f..d412c0c00 100644
--- a/src/pleroma.ts
+++ b/src/pleroma.ts
@@ -1,6 +1,5 @@
-import { MegalodonInterface, NoImplementedError } from './megalodon'
+import { MegalodonInterface, StreamListenerInterface, NoImplementedError } from './megalodon'
 import Mastodon from './mastodon'
-import StreamListener from './stream_listener'
 import Response from './response'
 import Entity from './entity'
 import PleromaAPI from './pleroma/api_client'
@@ -57,27 +56,27 @@ export default class Pleroma extends Mastodon implements MegalodonInterface {
   // ======================================
   // HTTP Streaming
   // ======================================
-  public userStream(): StreamListener {
+  public userStream(): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 
-  public publicStream(): StreamListener {
+  public publicStream(): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 
-  public localStream(): StreamListener {
+  public localStream(): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 
-  public tagStream(_tag: string): StreamListener {
+  public tagStream(_tag: string): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 
-  public listStream(_list_id: string): StreamListener {
+  public listStream(_list_id: string): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 
-  public directStream(): StreamListener {
+  public directStream(): StreamListenerInterface {
     throw new NoImplementedError('pleroma does not support')
   }
 }
diff --git a/test/unit/webo_socket.spec.ts b/test/unit/webo_socket.spec.ts
index 5000c584e..faa5b1f16 100644
--- a/test/unit/webo_socket.spec.ts
+++ b/test/unit/webo_socket.spec.ts
@@ -1,4 +1,4 @@
-import { Parser } from '@/web_socket'
+import { Parser } from '@/mastodon/web_socket'
 import Entity from '@/entity'
 
 const account: Entity.Account = {