diff --git a/back/volume/.eslintrc.js b/back/volume/.eslintrc.js
new file mode 100644
index 0000000..68e0778
--- /dev/null
+++ b/back/volume/.eslintrc.js
@@ -0,0 +1,13 @@
+module.exports = {
+  env: {
+    browser: true,
+    es2021: true
+  },
+  extends: 'standard-with-typescript',
+  parserOptions: {
+    ecmaVersion: 'latest',
+    sourceType: 'module',
+    project: ['./tsconfig.json'],
+    tsconfigRootDir: __dirname
+  }
+}
diff --git a/back/volume/.eslintrc.json b/back/volume/.eslintrc.json
deleted file mode 100644
index 039d3de..0000000
--- a/back/volume/.eslintrc.json
+++ /dev/null
@@ -1,16 +0,0 @@
-{
-    "env": {
-        "browser": true,
-        "es2021": true
-    },
-    "extends": "standard-with-typescript",
-    "overrides": [
-    ],
-    "parserOptions": {
-        "ecmaVersion": "latest",
-        "sourceType": "module",
-        "project": ["./tsconfig.json"]
-    },
-    "rules": {
-    }
-}
diff --git a/back/volume/package.json b/back/volume/package.json
index 86e3b79..3cd70da 100644
--- a/back/volume/package.json
+++ b/back/volume/package.json
@@ -8,12 +8,12 @@
   "scripts": {
     "prebuild": "rimraf dist",
     "build": "nest build",
-    "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\"",
+    "format": "prettier --write \".eslintrc.js\" \"src/**/*.ts\"",
     "start": "nest start",
     "dev": "nest start --watch",
     "start:debug": "nest start --debug --watch",
     "start:prod": "node dist/main",
-    "lint": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
+    "lint": "eslint \".eslintrc.js\" \"{src,apps,libs,test}/**/*.ts\" --fix",
     "test": "jest",
     "test:watch": "jest --watch",
     "test:cov": "jest --coverage",
diff --git a/back/volume/src/main.ts b/back/volume/src/main.ts
index eac5e10..5efb7b2 100644
--- a/back/volume/src/main.ts
+++ b/back/volume/src/main.ts
@@ -2,9 +2,9 @@ import { NestFactory } from '@nestjs/core'
 import { WsAdapter } from '@nestjs/platform-ws'
 import { AppModule } from './app.module'
 
-async function bootstrap () {
+async function bootstrap (): Promise<void> {
   const app = await NestFactory.create(AppModule)
   app.useWebSocketAdapter(new WsAdapter(app))
   await app.listen(3001)
 }
-bootstrap()
+void bootstrap()
diff --git a/back/volume/src/pong/dtos/PlayerNamesDto.ts b/back/volume/src/pong/dtos/PlayerNamesDto.ts
index 8b4faa3..d03d682 100644
--- a/back/volume/src/pong/dtos/PlayerNamesDto.ts
+++ b/back/volume/src/pong/dtos/PlayerNamesDto.ts
@@ -4,5 +4,5 @@ export class PlayerNamesDto {
   @IsString({ each: true })
   @ArrayMaxSize(2)
   @ArrayMinSize(2)
-    playerNames: string[]
+    playerNames!: string[]
 }
diff --git a/back/volume/src/pong/dtos/UserDto.ts b/back/volume/src/pong/dtos/UserDto.ts
index 4abc1f4..10880a7 100644
--- a/back/volume/src/pong/dtos/UserDto.ts
+++ b/back/volume/src/pong/dtos/UserDto.ts
@@ -1,12 +1,12 @@
-import { ArrayMaxSize, ArrayMinSize, IsString } from 'class-validator'
+import { IsString } from 'class-validator'
 
 export class UserDto {
   @IsString()
-    username: string
+    username!: string
 
   @IsString()
-    avatar: string
+    avatar!: string
 
   @IsString()
-    status: string
+    status!: string
 }
diff --git a/back/volume/src/pong/game/Ball.ts b/back/volume/src/pong/game/Ball.ts
index 2db6d33..949a019 100644
--- a/back/volume/src/pong/game/Ball.ts
+++ b/back/volume/src/pong/game/Ball.ts
@@ -16,22 +16,23 @@ export class Ball {
     this.rect = new Rect(spawn, size)
     this.speed = speed
     this.spawn = spawn.clone()
+    this.indexPlayerScored = -1
   }
 
   getIndexPlayerScored (): number {
     return this.indexPlayerScored
   }
 
-  update (canvas_rect: Rect, paddles: Paddle[]) {
-    if (!canvas_rect.contains_x(this.rect)) {
+  update (canvasRect: Rect, paddles: Paddle[]): void {
+    if (!canvasRect.contains_x(this.rect)) {
       this.indexPlayerScored = this.score()
     } else {
       this.indexPlayerScored = -1
-      this.move(canvas_rect, paddles)
+      this.move(canvasRect, paddles)
     }
   }
 
-  move (canvas_rect: Rect, paddles: Paddle[]) {
+  move (canvasRect: Rect, paddles: Paddle[]): void {
     for (const paddle of paddles) {
       if (paddle.rect.collides(this.rect)) {
         if (this.speed.x < 0) {
@@ -44,22 +45,22 @@ export class Ball {
         break
       }
     }
-    if (!canvas_rect.contains_y(this.rect)) this.speed.y = this.speed.y * -1
+    if (!canvasRect.contains_y(this.rect)) this.speed.y = this.speed.y * -1
     this.rect.center.add_inplace(this.speed)
   }
 
   // A player scored: return his index and reposition the ball
   score (): number {
-    let index_player_scored: number
+    let indexPlayerScored: number
     if (this.rect.center.x <= this.spawn.x) {
-      index_player_scored = 1
+      indexPlayerScored = 1
     } else {
-      index_player_scored = 0
+      indexPlayerScored = 0
     }
 
     this.rect.center = this.spawn.clone()
     this.speed.x = this.speed.x * -1
 
-    return index_player_scored
+    return indexPlayerScored
   }
 }
diff --git a/back/volume/src/pong/game/Game.ts b/back/volume/src/pong/game/Game.ts
index 1731f48..e2962ac 100644
--- a/back/volume/src/pong/game/Game.ts
+++ b/back/volume/src/pong/game/Game.ts
@@ -13,20 +13,20 @@ import { Spectator } from './Spectator'
 
 const GAME_TICKS = 30
 
-function gameLoop (game: Game) {
-  const canvas_rect = new Rect(
+function gameLoop (game: Game): void {
+  const canvasRect = new Rect(
     new Point(gameInfoConstants.mapSize.x / 2, gameInfoConstants.mapSize.y / 2),
     new Point(gameInfoConstants.mapSize.x, gameInfoConstants.mapSize.y)
   )
   game.ball.update(
-    canvas_rect,
+    canvasRect,
     game.players.map((p) => p.paddle)
   )
-  const index_player_scored: number = game.ball.getIndexPlayerScored()
-  if (index_player_scored != -1) {
-    game.players[index_player_scored].score += 1
-    if (game.players[index_player_scored].score >= gameInfoConstants.winScore) {
-      console.log(`${game.players[index_player_scored].name} won!`)
+  const indexPlayerScored: number = game.ball.getIndexPlayerScored()
+  if (indexPlayerScored !== -1) {
+    game.players[indexPlayerScored].score += 1
+    if (game.players[indexPlayerScored].score >= gameInfoConstants.winScore) {
+      console.log(`${game.players[indexPlayerScored].name} won!`)
       game.stop()
     }
   }
@@ -45,7 +45,7 @@ function gameLoop (game: Game) {
 
 export class Game {
   id: string
-  timer: NodeJS.Timer
+  timer: NodeJS.Timer | null
   ball: Ball
   players: Player[] = []
   spectators: Spectator[] = []
@@ -54,6 +54,7 @@ export class Game {
   constructor (sockets: WebSocket[], uuids: string[], names: string[]) {
     this.id = randomUUID()
     this.timer = null
+    this.playing = false
     this.ball = new Ball(
       new Point(
         gameInfoConstants.mapSize.x / 2,
@@ -66,7 +67,7 @@ export class Game {
   }
 
   getGameInfo (name: string): GameInfo {
-    const yourPaddleIndex = this.players.findIndex((p) => p.name == name)
+    const yourPaddleIndex = this.players.findIndex((p) => p.name === name)
     return {
       ...gameInfoConstants,
       yourPaddleIndex,
@@ -74,17 +75,17 @@ export class Game {
     }
   }
 
-  addSpectator (socket: WebSocket, uuid: string, name: string) {
+  addSpectator (socket: WebSocket, uuid: string, name: string): void {
     this.spectators.push(new Spectator(socket, uuid, name))
     console.log(`Added spectator ${name}`)
   }
 
-  private addPlayer (socket: WebSocket, uuid: string, name: string) {
+  private addPlayer (socket: WebSocket, uuid: string, name: string): void {
     let paddleCoords = new Point(
       gameInfoConstants.playerXOffset,
       gameInfoConstants.mapSize.y / 2
     )
-    if (this.players.length == 1) {
+    if (this.players.length === 1) {
       paddleCoords = new Point(
         gameInfoConstants.mapSize.x - gameInfoConstants.playerXOffset,
         gameInfoConstants.mapSize.y / 2
@@ -95,21 +96,21 @@ export class Game {
     )
   }
 
-  removePlayer (name: string) {
-    const player_index = this.players.findIndex((p) => p.name == name)
-    if (player_index != -1) {
-      this.players.splice(player_index, 1)
+  removePlayer (name: string): void {
+    const playerIndex: number = this.players.findIndex((p) => p.name === name)
+    if (playerIndex !== -1) {
+      this.players.splice(playerIndex, 1)
       if (this.players.length < 2) {
         this.stop()
       }
     }
   }
 
-  ready (name: string) {
-    const player_index = this.players.findIndex((p) => p.name == name)
-    if (player_index != -1) {
-      this.players[player_index].ready = true
-      console.log(`${this.players[player_index].name} is ready!`)
+  ready (name: string): void {
+    const playerIndex: number = this.players.findIndex((p) => p.name === name)
+    if (playerIndex !== -1) {
+      this.players[playerIndex].ready = true
+      console.log(`${this.players[playerIndex].name} is ready!`)
       if (this.players.every((p) => p.ready)) {
         this.start()
       }
@@ -117,7 +118,7 @@ export class Game {
   }
 
   private start (): boolean {
-    if (!this.timer && this.players.length == 2) {
+    if (this.timer === null && this.players.length === 2) {
       this.ball = new Ball(
         new Point(
           gameInfoConstants.mapSize.x / 2,
@@ -137,8 +138,8 @@ export class Game {
     return false
   }
 
-  stop () {
-    if (this.timer) {
+  stop (): void {
+    if (this.timer !== null) {
       clearInterval(this.timer)
       this.timer = null
       this.players = []
@@ -147,15 +148,15 @@ export class Game {
     }
   }
 
-  movePaddle (name: string, position: Point) {
-    const playerIndex = this.players.findIndex((p) => p.name == name)
+  movePaddle (name: string | undefined, position: Point): void {
+    const playerIndex: number = this.players.findIndex((p) => p.name === name)
 
-    if (this.timer && playerIndex != -1) {
+    if (this.timer !== null && playerIndex !== -1) {
       this.players[playerIndex].paddle.move(position.y)
     }
   }
 
-  broadcastGame (data: string) {
+  broadcastGame (data: string): void {
     this.players.forEach((p) => {
       p.socket.send(data)
     })
diff --git a/back/volume/src/pong/game/Paddle.ts b/back/volume/src/pong/game/Paddle.ts
index ad089be..4ce379b 100644
--- a/back/volume/src/pong/game/Paddle.ts
+++ b/back/volume/src/pong/game/Paddle.ts
@@ -15,18 +15,18 @@ export class Paddle {
     this.mapSize = gameSize
   }
 
-  draw (context: CanvasRenderingContext2D) {
+  draw (context: CanvasRenderingContext2D): void {
     this.rect.draw(context, this.color)
   }
 
-  move (new_y: number) {
+  move (newY: number): void {
     const offset: number = this.rect.size.y / 2
-    if (new_y - offset < 0) {
+    if (newY - offset < 0) {
       this.rect.center.y = offset
-    } else if (new_y + offset > this.mapSize.y) {
+    } else if (newY + offset > this.mapSize.y) {
       this.rect.center.y = this.mapSize.y - offset
     } else {
-      this.rect.center.y = new_y
+      this.rect.center.y = newY
     }
   }
 }
diff --git a/back/volume/src/pong/game/Player.ts b/back/volume/src/pong/game/Player.ts
index 3183acf..934838f 100644
--- a/back/volume/src/pong/game/Player.ts
+++ b/back/volume/src/pong/game/Player.ts
@@ -22,13 +22,14 @@ export class Player {
     this.socket = socket
     this.uuid = uuid
     this.name = name
+    this.ready = false
     this.paddle = new Paddle(paddleCoords, mapSize)
     this.paddleCoords = paddleCoords
     this.mapSize = mapSize
     this.score = 0
   }
 
-  newGame () {
+  newGame (): void {
     this.score = 0
     this.paddle = new Paddle(this.paddleCoords, this.mapSize)
   }
diff --git a/back/volume/src/pong/game/utils.ts b/back/volume/src/pong/game/utils.ts
index 90fe6ef..887f837 100644
--- a/back/volume/src/pong/game/utils.ts
+++ b/back/volume/src/pong/game/utils.ts
@@ -8,12 +8,12 @@ export class Point {
   }
 
   // Returns a new point
-  add (other: Point) {
+  add (other: Point): Point {
     return new Point(this.x + other.x, this.y + other.y)
   }
 
   // Modifies `this` point
-  add_inplace (other: Point) {
+  add_inplace (other: Point): void {
     this.x += other.x
     this.y += other.y
   }
@@ -35,7 +35,7 @@ export class Rect {
   draw (
     context: CanvasRenderingContext2D,
     color: string | CanvasGradient | CanvasPattern
-  ) {
+  ): void {
     const offset: Point = new Point(this.size.x / 2, this.size.y / 2)
 
     context.fillStyle = color
@@ -50,11 +50,11 @@ export class Rect {
   // True if `this` rect contains `other` rect in the x-axis
   contains_x (other: Rect): boolean {
     const offset: number = this.size.x / 2
-    const offset_other: number = other.size.x / 2
+    const offsetOther: number = other.size.x / 2
 
     if (
-      this.center.x - offset <= other.center.x - offset_other &&
-      this.center.x + offset >= other.center.x + offset_other
+      this.center.x - offset <= other.center.x - offsetOther &&
+      this.center.x + offset >= other.center.x + offsetOther
     ) {
       return true
     }
@@ -64,11 +64,11 @@ export class Rect {
   // True if `this` rect contains `other` rect in the y-axis
   contains_y (other: Rect): boolean {
     const offset: number = this.size.y / 2
-    const offset_other: number = other.size.y / 2
+    const offsetOther: number = other.size.y / 2
 
     if (
-      this.center.y - offset <= other.center.y - offset_other &&
-      this.center.y + offset >= other.center.y + offset_other
+      this.center.y - offset <= other.center.y - offsetOther &&
+      this.center.y + offset >= other.center.y + offsetOther
     ) {
       return true
     }
@@ -77,13 +77,13 @@ export class Rect {
 
   collides (other: Rect): boolean {
     const offset: Point = new Point(this.size.x / 2, this.size.y / 2)
-    const offset_other: Point = new Point(other.size.x / 2, other.size.y / 2)
+    const offsetOther: Point = new Point(other.size.x / 2, other.size.y / 2)
 
     if (
-      this.center.x - offset.x < other.center.x + offset_other.x &&
-      this.center.x + offset.x > other.center.x - offset_other.x &&
-      this.center.y - offset.y < other.center.y + offset_other.y &&
-      this.center.y + offset.y > other.center.y - offset_other.y
+      this.center.x - offset.x < other.center.x + offsetOther.x &&
+      this.center.x + offset.x > other.center.x - offsetOther.x &&
+      this.center.y - offset.y < other.center.y + offsetOther.y &&
+      this.center.y + offset.y > other.center.y - offsetOther.y
     ) {
       return true
     }
diff --git a/back/volume/src/pong/pong.gateway.ts b/back/volume/src/pong/pong.gateway.ts
index 090052a..28476ff 100644
--- a/back/volume/src/pong/pong.gateway.ts
+++ b/back/volume/src/pong/pong.gateway.ts
@@ -13,6 +13,7 @@ import { formatWebsocketData, Point } from './game/utils'
 import { GAME_EVENTS } from './game/constants'
 import { PlayerNamesDto } from './dtos/PlayerNamesDto'
 import { UsePipes, ValidationPipe } from '@nestjs/common'
+import { type Game } from './game/Game'
 
 interface WebSocketWithId extends WebSocket {
   id: string
@@ -23,20 +24,21 @@ export class PongGateway implements OnGatewayConnection, OnGatewayDisconnect {
   private readonly games: Games = new Games()
   private readonly socketToPlayerName = new Map<WebSocketWithId, string>()
 
-  handleConnection (client: WebSocketWithId) {
+  handleConnection (client: WebSocketWithId): void {
     const uuid = randomUUID()
     client.id = uuid
   }
 
   handleDisconnect (
-  @ConnectedSocket()
-    client: WebSocketWithId
-  ) {
-    const name: string = this.socketToPlayerName.get(client)
-    if (this.games.isInAGame(name)) {
-      console.log(`Disconnected ${this.socketToPlayerName.get(client)}`)
-      if (this.games.playerGame(name).isPlaying()) {
-        this.games.playerGame(name).stop()
+    @ConnectedSocket()
+      client: WebSocketWithId
+  ): void {
+    const name: string | undefined = this.socketToPlayerName.get(client)
+    const game: Game | null = this.games.playerGame(name)
+    if (game !== null) {
+      console.log('Disconnected ', this.socketToPlayerName.get(client))
+      if (game.isPlaying()) {
+        game.stop()
       }
       this.socketToPlayerName.delete(client)
     }
@@ -44,18 +46,18 @@ export class PongGateway implements OnGatewayConnection, OnGatewayDisconnect {
 
   @SubscribeMessage(GAME_EVENTS.REGISTER_PLAYER)
   registerPlayer (
-  @ConnectedSocket()
-    client: WebSocketWithId,
-    @MessageBody('playerName') playerName: string
-  ) {
+    @ConnectedSocket()
+      client: WebSocketWithId,
+      @MessageBody('playerName') playerName: string
+  ): void {
     this.socketToPlayerName.set(client, playerName)
-    console.log(`Connected ${this.socketToPlayerName.get(client)}`)
+    console.log('Connected ', this.socketToPlayerName.get(client))
   }
 
   @SubscribeMessage(GAME_EVENTS.GET_GAME_INFO)
-  getPlayerCount (@ConnectedSocket() client: WebSocketWithId) {
-    const name: string = this.socketToPlayerName.get(client)
-    if (name) {
+  getPlayerCount (@ConnectedSocket() client: WebSocketWithId): void {
+    const name: string | undefined = this.socketToPlayerName.get(client)
+    if (name !== undefined) {
       client.send(
         formatWebsocketData(
           GAME_EVENTS.GET_GAME_INFO,
@@ -67,29 +69,29 @@ export class PongGateway implements OnGatewayConnection, OnGatewayDisconnect {
 
   @SubscribeMessage(GAME_EVENTS.PLAYER_MOVE)
   movePlayer (
-  @ConnectedSocket()
-    client: WebSocketWithId,
-    @MessageBody('position') position: Point
-  ) {
-    const name: string = this.socketToPlayerName.get(client)
+    @ConnectedSocket()
+      client: WebSocketWithId,
+      @MessageBody('position') position: Point
+  ): void {
+    const name: string | undefined = this.socketToPlayerName.get(client)
     this.games.movePlayer(name, position)
   }
 
   @UsePipes(new ValidationPipe({ whitelist: true }))
   @SubscribeMessage(GAME_EVENTS.CREATE_GAME)
   createGame (
-  @ConnectedSocket()
-    client: WebSocketWithId,
-    @MessageBody() playerNamesDto: PlayerNamesDto
-  ) {
+    @ConnectedSocket()
+      client: WebSocketWithId,
+      @MessageBody() playerNamesDto: PlayerNamesDto
+  ): void {
     if (this.socketToPlayerName.size >= 2) {
-      const player1Socket: WebSocketWithId = Array.from(
+      const player1Socket: WebSocketWithId | undefined = Array.from(
         this.socketToPlayerName.keys()
       ).find(
         (key) =>
           this.socketToPlayerName.get(key) === playerNamesDto.playerNames[0]
       )
-      const player2Socket: WebSocketWithId = Array.from(
+      const player2Socket: WebSocketWithId | undefined = Array.from(
         this.socketToPlayerName.keys()
       ).find(
         (key) =>
@@ -97,8 +99,8 @@ export class PongGateway implements OnGatewayConnection, OnGatewayDisconnect {
       )
 
       if (
-        player1Socket &&
-        player2Socket &&
+        player1Socket !== undefined &&
+        player2Socket !== undefined &&
         (client.id === player1Socket.id || client.id === player2Socket.id) &&
         player1Socket.id !== player2Socket.id
       ) {
@@ -113,23 +115,23 @@ export class PongGateway implements OnGatewayConnection, OnGatewayDisconnect {
 
   @SubscribeMessage(GAME_EVENTS.READY)
   ready (
-  @ConnectedSocket()
-    client: WebSocketWithId
-  ) {
-    const name: string = this.socketToPlayerName.get(client)
-    if (name) {
+    @ConnectedSocket()
+      client: WebSocketWithId
+  ): void {
+    const name: string | undefined = this.socketToPlayerName.get(client)
+    if (name !== undefined) {
       this.games.ready(name)
     }
   }
 
   @SubscribeMessage(GAME_EVENTS.SPECTATE)
   spectate (
-  @ConnectedSocket()
-    client: WebSocketWithId,
-    @MessageBody('playerToSpectate') playerToSpectate: string
-  ) {
-    const name: string = this.socketToPlayerName.get(client)
-    if (name) {
+    @ConnectedSocket()
+      client: WebSocketWithId,
+      @MessageBody('playerToSpectate') playerToSpectate: string
+  ): void {
+    const name: string | undefined = this.socketToPlayerName.get(client)
+    if (name !== undefined) {
       this.games.spectateGame(playerToSpectate, client, client.id, name)
     }
   }
diff --git a/back/volume/src/pong/pong.ts b/back/volume/src/pong/pong.ts
index 63e64e4..f199195 100644
--- a/back/volume/src/pong/pong.ts
+++ b/back/volume/src/pong/pong.ts
@@ -2,56 +2,72 @@ import { type WebSocket } from 'ws'
 import { type GameInfo } from './game/constants'
 import { Game } from './game/Game'
 import { type Point } from './game/utils'
+import { gameInfoConstants } from './game/constants'
 
 export class Games {
   private readonly playerNameToGameIndex = new Map<string, number>()
   private readonly games = new Array<Game>()
 
-  newGame (sockets: WebSocket[], uuids: string[], names: string[]) {
+  newGame (sockets: WebSocket[], uuids: string[], names: string[]): void {
     this.games.push(new Game(sockets, uuids, names))
     this.playerNameToGameIndex.set(names[0], this.games.length - 1)
     this.playerNameToGameIndex.set(names[1], this.games.length - 1)
     console.log(`Created game ${names[0]} vs ${names[1]}`)
   }
 
-  removePlayer (name: string) {
-    this.playerGame(name).removePlayer(name)
+  removePlayer (name: string): void {
+    const game: Game | null = this.playerGame(name)
+    if (game !== null) {
+      game.removePlayer(name)
+    }
   }
 
-  ready (name: string) {
-    if (this.isInAGame(name)) {
-      this.playerGame(name).ready(name)
+  ready (name: string): void {
+    const game: Game | null = this.playerGame(name)
+    if (game !== null) {
+      game.ready(name)
     }
   }
 
-  stopGame (uuid: string) {
-    // if (this.isInAGame(uuid)) {
-    //   this.playerGame(uuid).stop()
-    //   delete this.playerNameToGameIndex[uuid]
-    //   delete this.games[this.playerNameToGameIndex[uuid]]
-    // }
-  }
+  // stopGame (uuid: string): void {
+  //   // if (this.isInAGame(uuid)) {
+  //   //   this.playerGame(uuid).stop()
+  //   //   delete this.playerNameToGameIndex[uuid]
+  //   //   delete this.games[this.playerNameToGameIndex[uuid]]
+  //   // }
+  // }
 
   getGameInfo (name: string): GameInfo {
-    if (this.isInAGame(name)) {
-      return this.playerGame(name).getGameInfo(name)
+    const game: Game | null = this.playerGame(name)
+    if (game !== null) {
+      return game.getGameInfo(name)
+    }
+    return {
+      ...gameInfoConstants,
+      yourPaddleIndex: 0,
+      gameId: ''
     }
   }
 
-  movePlayer (name: string, position: Point) {
-    if (this.isInAGame(name)) {
-      this.playerGame(name).movePaddle(name, position)
+  movePlayer (name: string | undefined, position: Point): void {
+    const game: Game | null = this.playerGame(name)
+    if (game !== null) {
+      game.movePaddle(name, position)
     }
   }
 
-  isInAGame (name: string): boolean {
+  isInAGame (name: string | undefined): boolean {
+    if (name === undefined) return false
     return this.playerNameToGameIndex.get(name) !== undefined
   }
 
-  playerGame (name: string): Game {
-    if (this.isInAGame(name)) {
-      return this.games[this.playerNameToGameIndex.get(name)]
+  playerGame (name: string | undefined): Game | null {
+    if (name === undefined) return null
+    const gameIndex: number | undefined = this.playerNameToGameIndex.get(name)
+    if (gameIndex !== undefined) {
+      return this.games[gameIndex]
     }
+    return null
   }
 
   spectateGame (
@@ -59,13 +75,12 @@ export class Games {
     socket: WebSocket,
     uuid: string,
     name: string
-  ) {
-    if (this.isInAGame(nameToSpectate)) {
-      this.playerNameToGameIndex.set(
-        name,
-        this.playerNameToGameIndex.get(nameToSpectate)
-      )
-      this.playerGame(nameToSpectate).addSpectator(socket, uuid, name)
+  ): void {
+    const gameIndex: number | undefined =
+      this.playerNameToGameIndex.get(nameToSpectate)
+    if (gameIndex !== undefined) {
+      this.playerNameToGameIndex.set(name, gameIndex)
+      this.games[gameIndex].addSpectator(socket, uuid, name)
     }
   }
 }
diff --git a/back/volume/test/app.e2e-spec.ts b/back/volume/test/app.e2e-spec.ts
deleted file mode 100644
index e3fc5d0..0000000
--- a/back/volume/test/app.e2e-spec.ts
+++ /dev/null
@@ -1,24 +0,0 @@
-import { Test, type TestingModule } from '@nestjs/testing'
-import { type INestApplication } from '@nestjs/common'
-import * as request from 'supertest'
-import { AppModule } from './../src/app.module'
-
-describe('AppController (e2e)', () => {
-  let app: INestApplication
-
-  beforeEach(async () => {
-    const moduleFixture: TestingModule = await Test.createTestingModule({
-      imports: [AppModule]
-    }).compile()
-
-    app = moduleFixture.createNestApplication()
-    await app.init()
-  })
-
-  it('/ (GET)', async () => {
-    return await request(app.getHttpServer())
-      .get('/')
-      .expect(200)
-      .expect('Hello World!')
-  })
-})
diff --git a/back/volume/test/jest-e2e.json b/back/volume/test/jest-e2e.json
deleted file mode 100644
index e9d912f..0000000
--- a/back/volume/test/jest-e2e.json
+++ /dev/null
@@ -1,9 +0,0 @@
-{
-  "moduleFileExtensions": ["js", "json", "ts"],
-  "rootDir": ".",
-  "testEnvironment": "node",
-  "testRegex": ".e2e-spec.ts$",
-  "transform": {
-    "^.+\\.(t|j)s$": "ts-jest"
-  }
-}
diff --git a/back/volume/tsconfig.json b/back/volume/tsconfig.json
index 12cebf4..8f7ee28 100644
--- a/back/volume/tsconfig.json
+++ b/back/volume/tsconfig.json
@@ -12,10 +12,6 @@
     "baseUrl": "./",
     "incremental": true,
     "skipLibCheck": true,
-    "strictNullChecks": false,
-    "noImplicitAny": false,
-    "strictBindCallApply": false,
-    "forceConsistentCasingInFileNames": false,
-    "noFallthroughCasesInSwitch": false
+    "strict": true
   }
 }
\ No newline at end of file