diff --git a/eslint.config.js b/eslint.config.js
index d0ebfde9a..05c378288 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -48,10 +48,20 @@ export default [
   {
     rules: {
       // Enable rules
-      "@typescript-eslint/consistent-type-assertions": [
-        "warn", // TODO: Raise this to error, https://github.com/openfrontio/OpenFrontIO/issues/1033
-        { assertionStyle: "never" },
+      "@typescript-eslint/consistent-type-definitions": [
+        "error",
+        "type",
+        // TODO: { assertionStyle: "never" }, https://github.com/openfrontio/OpenFrontIO/issues/1033
       ],
+      "@typescript-eslint/no-duplicate-enum-values": "error",
+      "@typescript-eslint/no-inferrable-types": "error",
+      "@typescript-eslint/no-mixed-enums": "error",
+      "@typescript-eslint/no-require-imports": "error",
+      "@typescript-eslint/no-unnecessary-type-assertion": "error",
+      "@typescript-eslint/prefer-as-const": "error",
+      "@typescript-eslint/prefer-function-type": "error",
+      "@typescript-eslint/prefer-includes": "error",
+      "@typescript-eslint/prefer-literal-enum-member": "error",
       "@typescript-eslint/prefer-nullish-coalescing": "error",
       eqeqeq: "error",
       "sort-keys": "error",
diff --git a/src/client/ClientGameRunner.ts b/src/client/ClientGameRunner.ts
index eab9a3393..b96cd8257 100644
--- a/src/client/ClientGameRunner.ts
+++ b/src/client/ClientGameRunner.ts
@@ -47,7 +47,7 @@ import {
 import { createCanvas } from "./Utils";
 import { createRenderer, GameRenderer } from "./graphics/GameRenderer";
 
-export interface LobbyConfig {
+export type LobbyConfig = {
   serverConfig: ServerConfig;
   pattern: string | undefined;
   flag: string;
@@ -59,7 +59,7 @@ export interface LobbyConfig {
   gameStartInfo?: GameStartInfo;
   // GameRecord exists when replaying an archived game.
   gameRecord?: GameRecord;
-}
+};
 
 export function joinLobby(
   eventBus: EventBus,
@@ -192,7 +192,7 @@ export class ClientGameRunner {
 
   private lastMousePosition: { x: number; y: number } | null = null;
 
-  private lastMessageTime: number = 0;
+  private lastMessageTime = 0;
   private connectionCheckInterval: NodeJS.Timeout | null = null;
 
   constructor(
@@ -364,7 +364,7 @@ export class ClientGameRunner {
     this.transport.connect(onconnect, onmessage);
   }
 
-  public stop(saveFullGame: boolean = false) {
+  public stop(saveFullGame = false) {
     if (!this.isActive) return;
 
     this.isActive = false;
@@ -420,7 +420,7 @@ export class ClientGameRunner {
 
       const owner = this.gameView.owner(tile);
       if (owner.isPlayer()) {
-        this.gameView.setFocusedPlayer(owner as PlayerView);
+        this.gameView.setFocusedPlayer(owner);
       } else {
         this.gameView.setFocusedPlayer(null);
       }
@@ -623,7 +623,7 @@ export class ClientGameRunner {
     if (this.gameView.isLand(tile)) {
       const owner = this.gameView.owner(tile);
       if (owner.isPlayer()) {
-        this.gameView.setFocusedPlayer(owner as PlayerView);
+        this.gameView.setFocusedPlayer(owner);
       } else {
         this.gameView.setFocusedPlayer(null);
       }
@@ -637,7 +637,7 @@ export class ClientGameRunner {
         .sort((a, b) => a.distSquared - b.distSquared);
 
       if (units.length > 0) {
-        this.gameView.setFocusedPlayer(units[0].unit.owner() as PlayerView);
+        this.gameView.setFocusedPlayer(units[0].unit.owner());
       } else {
         this.gameView.setFocusedPlayer(null);
       }
diff --git a/src/client/FlagInput.ts b/src/client/FlagInput.ts
index 584253700..aeb1f0493 100644
--- a/src/client/FlagInput.ts
+++ b/src/client/FlagInput.ts
@@ -1,11 +1,11 @@
 import { LitElement, css, html } from "lit";
 import { customElement, state } from "lit/decorators.js";
 import { renderPlayerFlag } from "../core/CustomFlag";
-const flagKey: string = "flag";
+const flagKey = "flag";
 
 @customElement("flag-input")
 export class FlagInput extends LitElement {
-  @state() public flag: string = "";
+  @state() public flag = "";
 
   static styles = css`
     @media (max-width: 768px) {
diff --git a/src/client/FlagInputModal.ts b/src/client/FlagInputModal.ts
index 86e413677..eb4b65ad3 100644
--- a/src/client/FlagInputModal.ts
+++ b/src/client/FlagInputModal.ts
@@ -9,7 +9,7 @@ export class FlagInputModal extends LitElement {
     close: () => void;
   };
 
-  @state() private search: string = "";
+  @state() private search = "";
 
   createRenderRoot() {
     return this;
diff --git a/src/client/GoogleAdElement.ts b/src/client/GoogleAdElement.ts
index 8d86e47fa..2d22d33bc 100644
--- a/src/client/GoogleAdElement.ts
+++ b/src/client/GoogleAdElement.ts
@@ -2,6 +2,7 @@ import { LitElement, css, html } from "lit";
 import { customElement, property } from "lit/decorators.js";
 
 declare global {
+  // eslint-disable-next-line @typescript-eslint/consistent-type-definitions
   interface Window {
     adsbygoogle: unknown[];
   }
@@ -108,7 +109,7 @@ const isElectron = () => {
   if (
     typeof navigator === "object" &&
     typeof navigator.userAgent === "string" &&
-    navigator.userAgent.indexOf("Electron") >= 0
+    navigator.userAgent.includes("Electron")
   ) {
     return true;
   }
diff --git a/src/client/HostLobbyModal.ts b/src/client/HostLobbyModal.ts
index 63a73731f..05905b922 100644
--- a/src/client/HostLobbyModal.ts
+++ b/src/client/HostLobbyModal.ts
@@ -40,19 +40,19 @@ export class HostLobbyModal extends LitElement {
   @state() private disableNPCs = false;
   @state() private gameMode: GameMode = GameMode.FFA;
   @state() private teamCount: TeamCountConfig = 2;
-  @state() private bots: number = 400;
-  @state() private infiniteGold: boolean = false;
-  @state() private donateGold: boolean = false;
-  @state() private infiniteTroops: boolean = false;
-  @state() private donateTroops: boolean = false;
-  @state() private instantBuild: boolean = false;
+  @state() private bots = 400;
+  @state() private infiniteGold = false;
+  @state() private donateGold = false;
+  @state() private infiniteTroops = false;
+  @state() private donateTroops = false;
+  @state() private instantBuild = false;
   @state() private lobbyId = "";
   @state() private copySuccess = false;
   @state() private clients: ClientInfo[] = [];
-  @state() private useRandomMap: boolean = false;
+  @state() private useRandomMap = false;
   @state() private disabledUnits: UnitType[] = [];
-  @state() private lobbyCreatorClientID: string = "";
-  @state() private lobbyIdVisible: boolean = true;
+  @state() private lobbyCreatorClientID = "";
+  @state() private lobbyIdVisible = true;
 
   private playersInterval: NodeJS.Timeout | null = null;
   // Add a new timer for debouncing bot changes
diff --git a/src/client/InputHandler.ts b/src/client/InputHandler.ts
index 5b9d397a8..5f0ab44e6 100644
--- a/src/client/InputHandler.ts
+++ b/src/client/InputHandler.ts
@@ -115,17 +115,17 @@ export class AutoUpgradeEvent implements GameEvent {
 }
 
 export class InputHandler {
-  private lastPointerX: number = 0;
-  private lastPointerY: number = 0;
+  private lastPointerX = 0;
+  private lastPointerY = 0;
 
-  private lastPointerDownX: number = 0;
-  private lastPointerDownY: number = 0;
+  private lastPointerDownX = 0;
+  private lastPointerDownY = 0;
 
   private pointers: Map<number, PointerEvent> = new Map();
 
-  private lastPinchDistance: number = 0;
+  private lastPinchDistance = 0;
 
-  private pointerDown: boolean = false;
+  private pointerDown = false;
 
   private alternateView = false;
 
@@ -163,7 +163,7 @@ export class InputHandler {
     };
 
     // Mac users might have different keybinds
-    const isMac = /Mac/.test(navigator.userAgent);
+    const isMac = navigator.userAgent.includes("Mac");
     if (isMac) {
       this.keybinds.modifierKey = "MetaLeft"; // Use Command key on Mac
     }
diff --git a/src/client/JoinPrivateLobbyModal.ts b/src/client/JoinPrivateLobbyModal.ts
index a4a4a0809..d67697836 100644
--- a/src/client/JoinPrivateLobbyModal.ts
+++ b/src/client/JoinPrivateLobbyModal.ts
@@ -19,7 +19,7 @@ export class JoinPrivateLobbyModal extends LitElement {
     close: () => void;
   };
   @query("#lobbyIdInput") private lobbyIdInput!: HTMLInputElement;
-  @state() private message: string = "";
+  @state() private message = "";
   @state() private hasJoined = false;
   @state() private players: string[] = [];
 
@@ -110,7 +110,7 @@ export class JoinPrivateLobbyModal extends LitElement {
     return this; // light DOM
   }
 
-  public open(id: string = "") {
+  public open(id = "") {
     this.modalEl?.open();
     if (id) {
       this.setLobbyId(id);
diff --git a/src/client/LangSelector.ts b/src/client/LangSelector.ts
index ca0424f22..2e6c5d51a 100644
--- a/src/client/LangSelector.ts
+++ b/src/client/LangSelector.ts
@@ -35,12 +35,12 @@ import zh_CN from "../../resources/lang/zh-CN.json";
 export class LangSelector extends LitElement {
   @state() public translations: Record<string, string> | undefined;
   @state() public defaultTranslations: Record<string, string> | undefined;
-  @state() public currentLang: string = "en";
+  @state() public currentLang = "en";
   @state() private languageList: any[] = [];
-  @state() private showModal: boolean = false;
-  @state() private debugMode: boolean = false;
+  @state() private showModal = false;
+  @state() private debugMode = false;
 
-  private debugKeyPressed: boolean = false;
+  private debugKeyPressed = false;
 
   private languageMap: Record<string, any> = {
     ar,
diff --git a/src/client/LocalServer.ts b/src/client/LocalServer.ts
index 24cf46782..cd195b28a 100644
--- a/src/client/LocalServer.ts
+++ b/src/client/LocalServer.ts
@@ -169,7 +169,7 @@ export class LocalServer {
     });
   }
 
-  public endGame(saveFullGame: boolean = false) {
+  public endGame(saveFullGame = false) {
     console.log("local server ending game");
     clearInterval(this.turnCheckInterval);
     if (this.isReplay) {
diff --git a/src/client/Main.ts b/src/client/Main.ts
index 97cca212c..55b7c75b0 100644
--- a/src/client/Main.ts
+++ b/src/client/Main.ts
@@ -43,6 +43,7 @@ import { discordLogin, getUserMe, isLoggedIn, logOut } from "./jwt";
 import "./styles.css";
 
 declare global {
+  // eslint-disable-next-line @typescript-eslint/consistent-type-definitions
   interface Window {
     PageOS: {
       session: {
@@ -62,13 +63,14 @@ declare global {
   }
 
   // Extend the global interfaces to include your custom events
+  // eslint-disable-next-line @typescript-eslint/consistent-type-definitions
   interface DocumentEventMap {
     "join-lobby": CustomEvent<JoinLobbyEvent>;
-    "kick-player": CustomEvent;
+    "kick-player": CustomEvent<KickPlayerEvent>;
   }
 }
 
-export interface JoinLobbyEvent {
+export type JoinLobbyEvent = {
   clientID: string;
   // Multiplayer games only have gameID, gameConfig is not known until game starts.
   gameID: string;
@@ -76,7 +78,11 @@ export interface JoinLobbyEvent {
   gameStartInfo?: GameStartInfo;
   // GameRecord exists when replaying an archived game.
   gameRecord?: GameRecord;
-}
+};
+
+export type KickPlayerEvent = {
+  target: string;
+};
 
 class Client {
   private gameStop: (() => void) | null = null;
@@ -548,7 +554,7 @@ class Client {
     this.publicLobby.leaveLobby();
   }
 
-  private handleKickPlayer(event: CustomEvent) {
+  private handleKickPlayer(event: CustomEvent<KickPlayerEvent>) {
     const { target } = event.detail;
 
     // Forward to eventBus if available
diff --git a/src/client/NewsModal.ts b/src/client/NewsModal.ts
index ddfa1fdc5..e3aeef95a 100644
--- a/src/client/NewsModal.ts
+++ b/src/client/NewsModal.ts
@@ -32,7 +32,7 @@ export class NewsModal extends LitElement {
 
   @property({ type: String }) markdown = "Loading...";
 
-  private initialized: boolean = false;
+  private initialized = false;
 
   static styles = css`
     :host {
diff --git a/src/client/PublicLobby.ts b/src/client/PublicLobby.ts
index 512c63444..6ab99d2cd 100644
--- a/src/client/PublicLobby.ts
+++ b/src/client/PublicLobby.ts
@@ -11,12 +11,12 @@ import { terrainMapFileLoader } from "./TerrainMapFileLoader";
 @customElement("public-lobby")
 export class PublicLobby extends LitElement {
   @state() private lobbies: GameInfo[] = [];
-  @state() public isLobbyHighlighted: boolean = false;
-  @state() private isButtonDebounced: boolean = false;
+  @state() public isLobbyHighlighted = false;
+  @state() private isButtonDebounced = false;
   @state() private mapImages: Map<GameID, string> = new Map();
   private lobbiesInterval: number | null = null;
   private currLobby: GameInfo | null = null;
-  private debounceDelay: number = 750;
+  private debounceDelay = 750;
   private lobbyIDToStart = new Map<GameID, number>();
 
   createRenderRoot() {
diff --git a/src/client/SinglePlayerModal.ts b/src/client/SinglePlayerModal.ts
index 3f1256403..657ef62a3 100644
--- a/src/client/SinglePlayerModal.ts
+++ b/src/client/SinglePlayerModal.ts
@@ -34,14 +34,14 @@ export class SinglePlayerModal extends LitElement {
   };
   @state() private selectedMap: GameMapType = GameMapType.World;
   @state() private selectedDifficulty: Difficulty = Difficulty.Medium;
-  @state() private disableNPCs: boolean = false;
-  @state() private bots: number = 400;
-  @state() private infiniteGold: boolean = false;
-  @state() private donateGold: boolean = false;
-  @state() private infiniteTroops: boolean = false;
-  @state() private donateTroops: boolean = false;
-  @state() private instantBuild: boolean = false;
-  @state() private useRandomMap: boolean = false;
+  @state() private disableNPCs = false;
+  @state() private bots = 400;
+  @state() private infiniteGold = false;
+  @state() private donateGold = false;
+  @state() private infiniteTroops = false;
+  @state() private donateTroops = false;
+  @state() private instantBuild = false;
+  @state() private useRandomMap = false;
   @state() private gameMode: GameMode = GameMode.FFA;
   @state() private teamCount: TeamCountConfig = 2;
 
diff --git a/src/client/TerritoryPatternsModal.ts b/src/client/TerritoryPatternsModal.ts
index 74e8e6857..3fd321faa 100644
--- a/src/client/TerritoryPatternsModal.ts
+++ b/src/client/TerritoryPatternsModal.ts
@@ -19,7 +19,7 @@ export class TerritoryPatternsModal extends LitElement {
   };
 
   public previewButton: HTMLElement | null = null;
-  public buttonWidth: number = 150;
+  public buttonWidth = 150;
 
   @state() private selectedPattern: string | undefined;
 
@@ -172,7 +172,7 @@ export class TerritoryPatternsModal extends LitElement {
                 }}
               >
                 ${translateText("territory_patterns.purchase")}
-                (${pattern.product!.price})
+                (${pattern.product.price})
               </button>
             `
           : null}
diff --git a/src/client/Transport.ts b/src/client/Transport.ts
index 200ae13d6..688fc5eee 100644
--- a/src/client/Transport.ts
+++ b/src/client/Transport.ts
@@ -383,7 +383,7 @@ export class Transport {
     } satisfies ClientJoinMessage);
   }
 
-  leaveGame(saveFullGame: boolean = false) {
+  leaveGame(saveFullGame = false) {
     if (this.isLocal) {
       this.localServer.endGame(saveFullGame);
       return;
diff --git a/src/client/UsernameInput.ts b/src/client/UsernameInput.ts
index 3b3c24b7d..04dce6436 100644
--- a/src/client/UsernameInput.ts
+++ b/src/client/UsernameInput.ts
@@ -8,13 +8,13 @@ import {
   validateUsername,
 } from "../core/validations/username";
 
-const usernameKey: string = "username";
+const usernameKey = "username";
 
 @customElement("username-input")
 export class UsernameInput extends LitElement {
-  @state() private username: string = "";
-  @property({ type: String }) validationError: string = "";
-  private _isValid: boolean = true;
+  @state() private username = "";
+  @property({ type: String }) validationError = "";
+  private _isValid = true;
   private userSettings: UserSettings = new UserSettings();
 
   // Remove static styles since we're using Tailwind
diff --git a/src/client/Utils.ts b/src/client/Utils.ts
index 494109fbd..118474bec 100644
--- a/src/client/Utils.ts
+++ b/src/client/Utils.ts
@@ -192,7 +192,7 @@ export function getMessageTypeClasses(type: MessageType): string {
 }
 
 export function getModifierKey(): string {
-  const isMac = /Mac/.test(navigator.userAgent);
+  const isMac = navigator.userAgent.includes("Mac");
   if (isMac) {
     return "⌘"; // Command key
   } else {
@@ -201,7 +201,7 @@ export function getModifierKey(): string {
 }
 
 export function getAltKey(): string {
-  const isMac = /Mac/.test(navigator.userAgent);
+  const isMac = navigator.userAgent.includes("Mac");
   if (isMac) {
     return "⌥"; // Option key
   } else {
diff --git a/src/client/components/Maps.ts b/src/client/components/Maps.ts
index 0b118c0d4..77a0bab88 100644
--- a/src/client/components/Maps.ts
+++ b/src/client/components/Maps.ts
@@ -41,7 +41,7 @@ export const MapDescription: Record<keyof typeof GameMapType, string> = {
 export class MapDisplay extends LitElement {
   @property({ type: String }) mapKey = "";
   @property({ type: Boolean }) selected = false;
-  @property({ type: String }) translation: string = "";
+  @property({ type: String }) translation = "";
   @state() private mapWebpPath: string | null = null;
   @state() private mapName: string | null = null;
   @state() private isLoading = true;
diff --git a/src/client/components/ModalOverlay.ts b/src/client/components/ModalOverlay.ts
index 468de56eb..772a7399b 100644
--- a/src/client/components/ModalOverlay.ts
+++ b/src/client/components/ModalOverlay.ts
@@ -3,7 +3,7 @@ import { customElement, property } from "lit/decorators";
 
 @customElement("modal-overlay")
 export class ModalOverlay extends LitElement {
-  @property({ reflect: true }) public visible: boolean = false;
+  @property({ reflect: true }) public visible = false;
 
   static styles = css`
     .overlay {
diff --git a/src/client/graphics/AnimatedSprite.ts b/src/client/graphics/AnimatedSprite.ts
index 5fea319d7..0cf108292 100644
--- a/src/client/graphics/AnimatedSprite.ts
+++ b/src/client/graphics/AnimatedSprite.ts
@@ -1,15 +1,15 @@
 export class AnimatedSprite {
   private frameHeight: number;
-  private currentFrame: number = 0;
-  private elapsedTime: number = 0;
-  private active: boolean = true;
+  private currentFrame = 0;
+  private elapsedTime = 0;
+  private active = true;
 
   constructor(
     private image: CanvasImageSource,
     private frameWidth: number,
     private frameCount: number,
     private frameDuration: number, // in milliseconds
-    private looping: boolean = false,
+    private looping = false,
     private originX: number,
     private originY: number,
   ) {
diff --git a/src/client/graphics/GameRenderer.ts b/src/client/graphics/GameRenderer.ts
index 3a089f33e..95164f163 100644
--- a/src/client/graphics/GameRenderer.ts
+++ b/src/client/graphics/GameRenderer.ts
@@ -246,7 +246,7 @@ export function createRenderer(
       eventBus,
       game,
       transformHandler,
-      emojiTable as EmojiTable,
+      emojiTable,
       buildMenu,
       uiState,
       playerPanel,
diff --git a/src/client/graphics/NameBoxCalculator.ts b/src/client/graphics/NameBoxCalculator.ts
index 328ac7aac..2d291c04d 100644
--- a/src/client/graphics/NameBoxCalculator.ts
+++ b/src/client/graphics/NameBoxCalculator.ts
@@ -1,17 +1,17 @@
 import { Cell, Game, NameViewData, Player } from "../../core/game/Game";
 import { calculateBoundingBox } from "../../core/Util";
 
-export interface Point {
+export type Point = {
   x: number;
   y: number;
-}
+};
 
-export interface Rectangle {
+export type Rectangle = {
   x: number;
   y: number;
   width: number;
   height: number;
-}
+};
 
 export function placeName(game: Game, player: Player): NameViewData {
   const boundingBox =
diff --git a/src/client/graphics/ProgressBar.ts b/src/client/graphics/ProgressBar.ts
index 52500bb87..5d186da6f 100644
--- a/src/client/graphics/ProgressBar.ts
+++ b/src/client/graphics/ProgressBar.ts
@@ -7,7 +7,7 @@ export class ProgressBar {
     private y: number,
     private w: number,
     private h: number,
-    private progress: number = 0, // Progress from 0 to 1
+    private progress = 0, // Progress from 0 to 1
   ) {
     this.setProgress(progress);
   }
diff --git a/src/client/graphics/TransformHandler.ts b/src/client/graphics/TransformHandler.ts
index 47b569d5a..252ee8042 100644
--- a/src/client/graphics/TransformHandler.ts
+++ b/src/client/graphics/TransformHandler.ts
@@ -13,10 +13,10 @@ export const CAMERA_MAX_SPEED = 15;
 export const CAMERA_SMOOTHING = 0.03;
 
 export class TransformHandler {
-  public scale: number = 1.8;
+  public scale = 1.8;
   private _boundingRect: DOMRect;
-  private offsetX: number = -350;
-  private offsetY: number = -200;
+  private offsetX = -350;
+  private offsetY = -200;
   private lastGoToCallTime: number | null = null;
 
   private target: Cell | null;
@@ -267,7 +267,7 @@ export class TransformHandler {
     this.target = null;
   }
 
-  override(x: number = 0, y: number = 0, s: number = 1) {
+  override(x = 0, y = 0, s = 1) {
     //hardset view position
     this.clearTarget();
     this.offsetX = x;
@@ -276,7 +276,7 @@ export class TransformHandler {
     this.changed = true;
   }
 
-  centerAll(fit: number = 1) {
+  centerAll(fit = 1) {
     //position entire map centered on the screen
 
     const vpWidth = this.boundingRect().width;
diff --git a/src/client/graphics/UIState.ts b/src/client/graphics/UIState.ts
index be985a580..839edc7fe 100644
--- a/src/client/graphics/UIState.ts
+++ b/src/client/graphics/UIState.ts
@@ -1,3 +1,3 @@
-export interface UIState {
+export type UIState = {
   attackRatio: number;
-}
+};
diff --git a/src/client/graphics/fx/Fx.ts b/src/client/graphics/fx/Fx.ts
index 2aeb3ccf6..051e0bb66 100644
--- a/src/client/graphics/fx/Fx.ts
+++ b/src/client/graphics/fx/Fx.ts
@@ -1,6 +1,6 @@
-export interface Fx {
+export type Fx = {
   renderTick(duration: number, ctx: CanvasRenderingContext2D): boolean;
-}
+};
 
 export enum FxType {
   MiniFire = "MiniFire",
diff --git a/src/client/graphics/fx/NukeFx.ts b/src/client/graphics/fx/NukeFx.ts
index 479d68e18..1394e2cbd 100644
--- a/src/client/graphics/fx/NukeFx.ts
+++ b/src/client/graphics/fx/NukeFx.ts
@@ -7,7 +7,7 @@ import { FadeFx, SpriteFx } from "./SpriteFx";
  * Shockwave effect: draw a growing 1px white circle
  */
 export class ShockwaveFx implements Fx {
-  private lifeTime: number = 0;
+  private lifeTime = 0;
   constructor(
     private x: number,
     private y: number,
diff --git a/src/client/graphics/fx/SpriteFx.ts b/src/client/graphics/fx/SpriteFx.ts
index 919533386..7dcd000b4 100644
--- a/src/client/graphics/fx/SpriteFx.ts
+++ b/src/client/graphics/fx/SpriteFx.ts
@@ -4,11 +4,7 @@ import { AnimatedSprite } from "../AnimatedSprite";
 import { AnimatedSpriteLoader } from "../AnimatedSpriteLoader";
 import { Fx, FxType } from "./Fx";
 
-function fadeInOut(
-  t: number,
-  fadeIn: number = 0.3,
-  fadeOut: number = 0.7,
-): number {
+function fadeInOut(t: number, fadeIn = 0.3, fadeOut = 0.7): number {
   if (t < fadeIn) {
     const f = t / fadeIn; // Map to [0, 1]
     return f * f;
diff --git a/src/client/graphics/fx/TextFx.ts b/src/client/graphics/fx/TextFx.ts
index c1a82e212..47eb68e32 100644
--- a/src/client/graphics/fx/TextFx.ts
+++ b/src/client/graphics/fx/TextFx.ts
@@ -1,15 +1,15 @@
 import { Fx } from "./Fx";
 
 export class TextFx implements Fx {
-  private lifeTime: number = 0;
+  private lifeTime = 0;
 
   constructor(
     private text: string,
     private x: number,
     private y: number,
     private duration: number,
-    private riseDistance: number = 30,
-    private font: string = "11px sans-serif",
+    private riseDistance = 30,
+    private font = "11px sans-serif",
     private color: { r: number; g: number; b: number } = {
       r: 255,
       g: 255,
diff --git a/src/client/graphics/layers/AlertFrame.ts b/src/client/graphics/layers/AlertFrame.ts
index cccff9efa..c792f8398 100644
--- a/src/client/graphics/layers/AlertFrame.ts
+++ b/src/client/graphics/layers/AlertFrame.ts
@@ -80,7 +80,7 @@ export class AlertFrame extends LitElement implements Layer {
     this.game
       .updatesSinceLastTick()
       ?.[GameUpdateType.BrokeAlliance]?.forEach((update) => {
-        this.onBrokeAllianceUpdate(update as BrokeAllianceUpdate);
+        this.onBrokeAllianceUpdate(update);
       });
   }
 
diff --git a/src/client/graphics/layers/BuildMenu.ts b/src/client/graphics/layers/BuildMenu.ts
index 9399218e9..d28a6ce63 100644
--- a/src/client/graphics/layers/BuildMenu.ts
+++ b/src/client/graphics/layers/BuildMenu.ts
@@ -35,13 +35,13 @@ import { renderNumber } from "../../Utils";
 import { TransformHandler } from "../TransformHandler";
 import { Layer } from "./Layer";
 
-export interface BuildItemDisplay {
+export type BuildItemDisplay = {
   unitType: UnitType;
   icon: string;
   description?: string;
   key?: string;
   countable?: boolean;
-}
+};
 
 export const buildTable: BuildItemDisplay[][] = [
   [
diff --git a/src/client/graphics/layers/ChatDisplay.ts b/src/client/graphics/layers/ChatDisplay.ts
index 941b08551..c2cadd0da 100644
--- a/src/client/graphics/layers/ChatDisplay.ts
+++ b/src/client/graphics/layers/ChatDisplay.ts
@@ -12,22 +12,22 @@ import { GameView } from "../../../core/game/GameView";
 import { onlyImages } from "../../../core/Util";
 import { Layer } from "./Layer";
 
-interface ChatEvent {
+type ChatEvent = {
   description: string;
   unsafeDescription?: boolean;
   createdAt: number;
   highlight?: boolean;
-}
+};
 
 @customElement("chat-display")
 export class ChatDisplay extends LitElement implements Layer {
   public eventBus: EventBus;
   public game: GameView;
 
-  private active: boolean = false;
+  private active = false;
 
-  @state() private _hidden: boolean = false;
-  @state() private newEvents: number = 0;
+  @state() private _hidden = false;
+  @state() private newEvents = 0;
   @state() private chatEvents: ChatEvent[] = [];
 
   private toggleHidden() {
diff --git a/src/client/graphics/layers/ChatModal.ts b/src/client/graphics/layers/ChatModal.ts
index 64023e66f..020ee8ac1 100644
--- a/src/client/graphics/layers/ChatModal.ts
+++ b/src/client/graphics/layers/ChatModal.ts
@@ -32,9 +32,9 @@ export class ChatModal extends LitElement {
 
   private players: PlayerView[] = [];
 
-  private playerSearchQuery: string = "";
+  private playerSearchQuery = "";
   private previewText: string | null = null;
-  private requiresPlayerSelection: boolean = false;
+  private requiresPlayerSelection = false;
   private selectedCategory: string | null = null;
   private selectedPhraseText: string | null = null;
   private selectedPhraseTemplate: string | null = null;
diff --git a/src/client/graphics/layers/ControlPanel.ts b/src/client/graphics/layers/ControlPanel.ts
index b10c81680..ea3ed9fdc 100644
--- a/src/client/graphics/layers/ControlPanel.ts
+++ b/src/client/graphics/layers/ControlPanel.ts
@@ -18,7 +18,7 @@ export class ControlPanel extends LitElement implements Layer {
   public uiState: UIState;
 
   @state()
-  private attackRatio: number = 0.2;
+  private attackRatio = 0.2;
 
   @state()
   private _maxTroops: number;
@@ -35,7 +35,7 @@ export class ControlPanel extends LitElement implements Layer {
   @state()
   private _gold: Gold;
 
-  private _troopRateIsIncreasing: boolean = true;
+  private _troopRateIsIncreasing = true;
 
   private _lastTroopIncreaseRate: number;
 
diff --git a/src/client/graphics/layers/EventsDisplay.ts b/src/client/graphics/layers/EventsDisplay.ts
index 3712f8faa..34e59adc3 100644
--- a/src/client/graphics/layers/EventsDisplay.ts
+++ b/src/client/graphics/layers/EventsDisplay.ts
@@ -48,7 +48,7 @@ import {
 
 import { getMessageTypeClasses, translateText } from "../../Utils";
 
-interface GameEvent {
+type GameEvent = {
   description: string;
   unsafeDescription?: boolean;
   buttons?: {
@@ -66,14 +66,14 @@ interface GameEvent {
   duration?: Tick;
   focusID?: number;
   unitView?: UnitView;
-}
+};
 
 @customElement("events-display")
 export class EventsDisplay extends LitElement implements Layer {
   public eventBus: EventBus;
   public game: GameView;
 
-  private active: boolean = false;
+  private active = false;
   private events: GameEvent[] = [];
 
   // allianceID -> last checked at tick
@@ -82,11 +82,11 @@ export class EventsDisplay extends LitElement implements Layer {
   @state() private outgoingAttacks: AttackUpdate[] = [];
   @state() private outgoingLandAttacks: AttackUpdate[] = [];
   @state() private outgoingBoats: UnitView[] = [];
-  @state() private _hidden: boolean = false;
-  @state() private _isVisible: boolean = false;
-  @state() private newEvents: number = 0;
+  @state() private _hidden = false;
+  @state() private _isVisible = false;
+  @state() private newEvents = 0;
   @state() private latestGoldAmount: bigint | null = null;
-  @state() private goldAmountAnimating: boolean = false;
+  @state() private goldAmountAnimating = false;
   private goldAmountTimeoutId: ReturnType<typeof setTimeout> | null = null;
   @state() private eventsFilters: Map<MessageCategory, boolean> = new Map([
     [MessageCategory.ATTACK, false],
@@ -261,7 +261,7 @@ export class EventsDisplay extends LitElement implements Layer {
 
       this.alliancesCheckedAt.set(alliance.id, this.game.ticks());
 
-      const other = this.game.player(alliance.other) as PlayerView;
+      const other = this.game.player(alliance.other);
       if (!other.isAlive()) continue;
 
       this.addEvent({
@@ -393,7 +393,7 @@ export class EventsDisplay extends LitElement implements Layer {
       }
     }
 
-    let otherPlayerDiplayName: string = "";
+    let otherPlayerDiplayName = "";
     if (event.recipient !== null) {
       //'recipient' parameter contains sender ID or recipient ID
       const player = this.game.player(event.recipient);
diff --git a/src/client/graphics/layers/FPSDisplay.ts b/src/client/graphics/layers/FPSDisplay.ts
index 37b3bb3cd..ded24567a 100644
--- a/src/client/graphics/layers/FPSDisplay.ts
+++ b/src/client/graphics/layers/FPSDisplay.ts
@@ -14,29 +14,29 @@ export class FPSDisplay extends LitElement implements Layer {
   public userSettings!: UserSettings;
 
   @state()
-  private currentFPS: number = 0;
+  private currentFPS = 0;
 
   @state()
-  private averageFPS: number = 0;
+  private averageFPS = 0;
 
   @state()
-  private frameTime: number = 0;
+  private frameTime = 0;
 
   @state()
-  private isVisible: boolean = false;
+  private isVisible = false;
 
   @state()
-  private isDragging: boolean = false;
+  private isDragging = false;
 
   @state()
   private position: { x: number; y: number } = { x: 50, y: 20 }; // Percentage values
 
-  private frameCount: number = 0;
-  private lastTime: number = 0;
+  private frameCount = 0;
+  private lastTime = 0;
   private frameTimes: number[] = [];
   private fpsHistory: number[] = [];
-  private lastSecondTime: number = 0;
-  private framesThisSecond: number = 0;
+  private lastSecondTime = 0;
+  private framesThisSecond = 0;
   private dragStart: { x: number; y: number } = { x: 0, y: 0 };
 
   static styles = css`
diff --git a/src/client/graphics/layers/FxLayer.ts b/src/client/graphics/layers/FxLayer.ts
index 1d33ab123..877ece3da 100644
--- a/src/client/graphics/layers/FxLayer.ts
+++ b/src/client/graphics/layers/FxLayer.ts
@@ -20,8 +20,8 @@ export class FxLayer implements Layer {
   private canvas: HTMLCanvasElement;
   private context: CanvasRenderingContext2D;
 
-  private lastRefresh: number = 0;
-  private refreshRate: number = 10;
+  private lastRefresh = 0;
+  private refreshRate = 10;
   private theme: Theme;
   private animatedSpriteLoader: AnimatedSpriteLoader =
     new AnimatedSpriteLoader();
diff --git a/src/client/graphics/layers/GameRightSidebar.ts b/src/client/graphics/layers/GameRightSidebar.ts
index 3ac7ce450..82d7f0a71 100644
--- a/src/client/graphics/layers/GameRightSidebar.ts
+++ b/src/client/graphics/layers/GameRightSidebar.ts
@@ -22,19 +22,19 @@ export class GameRightSidebar extends LitElement implements Layer {
   public eventBus: EventBus;
 
   @state()
-  private _isSinglePlayer: boolean = false;
+  private _isSinglePlayer = false;
 
   @state()
-  private _isReplayVisible: boolean = false;
+  private _isReplayVisible = false;
 
   @state()
-  private _isVisible: boolean = true;
+  private _isVisible = true;
 
   @state()
-  private isPaused: boolean = false;
+  private isPaused = false;
 
   @state()
-  private timer: number = 0;
+  private timer = 0;
 
   private hasWinner = false;
 
diff --git a/src/client/graphics/layers/GutterAdModal.ts b/src/client/graphics/layers/GutterAdModal.ts
index 707a04054..bc0027c68 100644
--- a/src/client/graphics/layers/GutterAdModal.ts
+++ b/src/client/graphics/layers/GutterAdModal.ts
@@ -13,16 +13,16 @@ export class GutterAdModal extends LitElement implements Layer {
   public eventBus: EventBus;
 
   @state()
-  private isVisible: boolean = false;
+  private isVisible = false;
 
   @state()
-  private adLoaded: boolean = false;
+  private adLoaded = false;
 
-  private leftAdType: string = "left_rail";
-  private rightAdType: string = "right_rail";
-  private leftContainerId: string = "gutter-ad-container-left";
-  private rightContainerId: string = "gutter-ad-container-right";
-  private margin: string = "10px";
+  private leftAdType = "left_rail";
+  private rightAdType = "right_rail";
+  private leftContainerId = "gutter-ad-container-left";
+  private rightContainerId = "gutter-ad-container-right";
+  private margin = "10px";
 
   // Override createRenderRoot to disable shadow DOM
   createRenderRoot() {
diff --git a/src/client/graphics/layers/Layer.ts b/src/client/graphics/layers/Layer.ts
index 239937435..36a850f78 100644
--- a/src/client/graphics/layers/Layer.ts
+++ b/src/client/graphics/layers/Layer.ts
@@ -1,7 +1,7 @@
-export interface Layer {
+export type Layer = {
   init?: () => void;
   tick?: () => void;
   renderLayer?: (context: CanvasRenderingContext2D) => void;
   shouldTransform?: () => boolean;
   redraw?: () => void;
-}
+};
diff --git a/src/client/graphics/layers/Leaderboard.ts b/src/client/graphics/layers/Leaderboard.ts
index 513aa2711..e117d82bb 100644
--- a/src/client/graphics/layers/Leaderboard.ts
+++ b/src/client/graphics/layers/Leaderboard.ts
@@ -7,7 +7,7 @@ import { GameView, PlayerView, UnitView } from "../../../core/game/GameView";
 import { renderNumber } from "../../Utils";
 import { Layer } from "./Layer";
 
-interface Entry {
+type Entry = {
   name: string;
   position: number;
   score: string;
@@ -15,7 +15,7 @@ interface Entry {
   troops: string;
   isMyPlayer: boolean;
   player: PlayerView;
-}
+};
 
 export class GoToPlayerEvent implements GameEvent {
   constructor(public player: PlayerView) {}
diff --git a/src/client/graphics/layers/MainRadialMenu.ts b/src/client/graphics/layers/MainRadialMenu.ts
index 002b488b0..8a5b48e57 100644
--- a/src/client/graphics/layers/MainRadialMenu.ts
+++ b/src/client/graphics/layers/MainRadialMenu.ts
@@ -110,7 +110,7 @@ export class MainRadialMenu extends LitElement implements Layer {
     this.buildMenu.playerActions = actions;
 
     const tileOwner = this.game.owner(tile);
-    const recipient = tileOwner.isPlayer() ? (tileOwner as PlayerView) : null;
+    const recipient = tileOwner.isPlayer() ? tileOwner : null;
 
     if (myPlayer && recipient) {
       this.chatIntegration.setupChatModal(myPlayer, recipient);
diff --git a/src/client/graphics/layers/MultiTabModal.ts b/src/client/graphics/layers/MultiTabModal.ts
index 312b092d6..94b8b6021 100644
--- a/src/client/graphics/layers/MultiTabModal.ts
+++ b/src/client/graphics/layers/MultiTabModal.ts
@@ -13,12 +13,12 @@ export class MultiTabModal extends LitElement implements Layer {
 
   private detector: MultiTabDetector;
 
-  @property({ type: Number }) duration: number = 5000;
-  @state() private countdown: number = 5;
-  @state() private isVisible: boolean = false;
-  @state() private fakeIp: string = "";
-  @state() private deviceFingerprint: string = "";
-  @state() private reported: boolean = true;
+  @property({ type: Number }) duration = 5000;
+  @state() private countdown = 5;
+  @state() private isVisible = false;
+  @state() private fakeIp = "";
+  @state() private deviceFingerprint = "";
+  @state() private reported = true;
 
   private intervalId?: number;
 
diff --git a/src/client/graphics/layers/NameLayer.ts b/src/client/graphics/layers/NameLayer.ts
index 2a1863c12..245fdcbb8 100644
--- a/src/client/graphics/layers/NameLayer.ts
+++ b/src/client/graphics/layers/NameLayer.ts
@@ -59,7 +59,7 @@ export class NameLayer implements Layer {
   private firstPlace: PlayerView | null = null;
   private theme: Theme = this.game.config().theme();
   private userSettings: UserSettings = new UserSettings();
-  private isVisible: boolean = true;
+  private isVisible = true;
 
   constructor(
     private game: GameView,
@@ -617,7 +617,7 @@ export class NameLayer implements Layer {
     src: string,
     size: number,
     id: string,
-    center: boolean = false,
+    center = false,
   ): HTMLImageElement {
     const icon = document.createElement("img");
     icon.src = src;
diff --git a/src/client/graphics/layers/OptionsMenu.ts b/src/client/graphics/layers/OptionsMenu.ts
index e0ee2004f..3290a1bef 100644
--- a/src/client/graphics/layers/OptionsMenu.ts
+++ b/src/client/graphics/layers/OptionsMenu.ts
@@ -48,23 +48,23 @@ export class OptionsMenu extends LitElement implements Layer {
   private userSettings: UserSettings = new UserSettings();
 
   @state()
-  private showPauseButton: boolean = true;
+  private showPauseButton = true;
 
   @state()
-  private isPaused: boolean = false;
+  private isPaused = false;
 
   @state()
-  private timer: number = 0;
+  private timer = 0;
 
   @state()
-  private showSettings: boolean = false;
+  private showSettings = false;
 
   private isVisible = false;
 
   private hasWinner = false;
 
   @state()
-  private alternateView: boolean = false;
+  private alternateView = false;
 
   private onTerrainButtonClick() {
     this.alternateView = !this.alternateView;
diff --git a/src/client/graphics/layers/PlayerInfoOverlay.ts b/src/client/graphics/layers/PlayerInfoOverlay.ts
index dab035023..f3aff01df 100644
--- a/src/client/graphics/layers/PlayerInfoOverlay.ts
+++ b/src/client/graphics/layers/PlayerInfoOverlay.ts
@@ -60,7 +60,7 @@ export class PlayerInfoOverlay extends LitElement implements Layer {
   private unit: UnitView | null = null;
 
   @state()
-  private _isInfoVisible: boolean = false;
+  private _isInfoVisible = false;
 
   private _isActive = false;
 
@@ -107,7 +107,7 @@ export class PlayerInfoOverlay extends LitElement implements Layer {
     const owner = this.game.owner(tile);
 
     if (owner && owner.isPlayer()) {
-      this.player = owner as PlayerView;
+      this.player = owner;
       this.player.profile().then((p) => {
         this.playerProfile = p;
       });
@@ -231,7 +231,7 @@ export class PlayerInfoOverlay extends LitElement implements Layer {
           }}
         >
           ${player.cosmetics.flag
-            ? player.cosmetics.flag!.startsWith("!")
+            ? player.cosmetics.flag.startsWith("!")
               ? html`<div
                   class="h-8 mr-1 aspect-[3/4] player-flag"
                   ${ref((el) => {
@@ -244,7 +244,7 @@ export class PlayerInfoOverlay extends LitElement implements Layer {
                 ></div>`
               : html`<img
                   class="h-8 mr-1 aspect-[3/4]"
-                  src=${"/flags/" + player.cosmetics.flag! + ".svg"}
+                  src=${"/flags/" + player.cosmetics.flag + ".svg"}
                 />`
             : html``}
           ${player.name()}
diff --git a/src/client/graphics/layers/PlayerPanel.ts b/src/client/graphics/layers/PlayerPanel.ts
index 7f4f425db..d70fbc1a7 100644
--- a/src/client/graphics/layers/PlayerPanel.ts
+++ b/src/client/graphics/layers/PlayerPanel.ts
@@ -40,7 +40,7 @@ export class PlayerPanel extends LitElement implements Layer {
   private tile: TileRef | null = null;
 
   @state()
-  public isVisible: boolean = false;
+  public isVisible = false;
 
   @state()
   private allianceExpiryText: string | null = null;
@@ -224,13 +224,12 @@ export class PlayerPanel extends LitElement implements Layer {
     const myPlayer = this.g.myPlayer();
     if (myPlayer === null) return;
     if (this.tile === null) return;
-    let other = this.g.owner(this.tile);
+    const other = this.g.owner(this.tile);
     if (!other.isPlayer()) {
       this.hide();
       console.warn("Tile is not owned by a player");
       return;
     }
-    other = other as PlayerView;
 
     const canDonateGold = this.actions?.interaction?.canDonateGold;
     const canDonateTroops = this.actions?.interaction?.canDonateTroops;
diff --git a/src/client/graphics/layers/RadialMenu.ts b/src/client/graphics/layers/RadialMenu.ts
index 9e81cc7cc..eeaa2dfc1 100644
--- a/src/client/graphics/layers/RadialMenu.ts
+++ b/src/client/graphics/layers/RadialMenu.ts
@@ -15,12 +15,12 @@ export class CloseRadialMenuEvent implements GameEvent {
   constructor() {}
 }
 
-export interface TooltipItem {
+export type TooltipItem = {
   text: string;
   className: string;
-}
+};
 
-export interface RadialMenuConfig {
+export type RadialMenuConfig = {
   menuSize?: number;
   submenuScale?: number;
   centerButtonSize?: number;
@@ -33,7 +33,7 @@ export interface RadialMenuConfig {
   maxNestedLevels?: number;
   innerRadiusIncrement?: number;
   tooltipStyle?: string;
-}
+};
 
 type CenterButtonState = "default" | "back";
 
@@ -42,9 +42,9 @@ type RequiredRadialMenuConfig = Required<RadialMenuConfig>;
 export class RadialMenu implements Layer {
   private menuElement: d3.Selection<HTMLDivElement, unknown, null, undefined>;
   private tooltipElement: HTMLDivElement | null = null;
-  private isVisible: boolean = false;
+  private isVisible = false;
 
-  private currentLevel: number = 0; // Current menu level (0 = main menu, 1 = submenu, etc.)
+  private currentLevel = 0; // Current menu level (0 = main menu, 1 = submenu, etc.)
   private menuStack: MenuElement[][] = []; // Stack to track menu navigation history
   private currentMenuItems: MenuElement[] = []; // Current active menu items (changes based on level)
 
@@ -53,9 +53,9 @@ export class RadialMenu implements Layer {
 
   private centerButtonState: CenterButtonState = "default";
 
-  private isTransitioning: boolean = false;
-  private lastHideTime: number = 0;
-  private reopenCooldownMs: number = 300;
+  private isTransitioning = false;
+  private lastHideTime = 0;
+  private reopenCooldownMs = 300;
 
   private menuGroups: Map<
     number,
@@ -73,8 +73,8 @@ export class RadialMenu implements Layer {
   private selectedItemId: string | null = null;
   private submenuHoverTimeout: number | null = null;
   private backButtonHoverTimeout: number | null = null;
-  private navigationInProgress: boolean = false;
-  private originalCenterButtonIcon: string = "";
+  private navigationInProgress = false;
+  private originalCenterButtonIcon = "";
 
   private params: MenuElementParams | null = null;
 
diff --git a/src/client/graphics/layers/RadialMenuElements.ts b/src/client/graphics/layers/RadialMenuElements.ts
index 3e2445d26..53e58a870 100644
--- a/src/client/graphics/layers/RadialMenuElements.ts
+++ b/src/client/graphics/layers/RadialMenuElements.ts
@@ -25,7 +25,7 @@ import traitorIcon from "../../../../resources/images/TraitorIconWhite.svg";
 import xIcon from "../../../../resources/images/XIcon.svg";
 import { EventBus } from "../../../core/EventBus";
 
-export interface MenuElementParams {
+export type MenuElementParams = {
   myPlayer: PlayerView;
   selected: PlayerView | null;
   tile: TileRef;
@@ -38,9 +38,9 @@ export interface MenuElementParams {
   chatIntegration: ChatIntegration;
   eventBus: EventBus;
   closeMenu: () => void;
-}
+};
 
-export interface MenuElement {
+export type MenuElement = {
   id: string;
   name: string;
   displayed?: boolean | ((params: MenuElementParams) => boolean);
@@ -54,18 +54,18 @@ export interface MenuElement {
   disabled: (params: MenuElementParams) => boolean;
   action?: (params: MenuElementParams) => void; // For leaf items that perform actions
   subMenu?: (params: MenuElementParams) => MenuElement[]; // For non-leaf items that open submenus
-}
+};
 
-export interface TooltipKey {
+export type TooltipKey = {
   key: string;
   className: string;
   params?: Record<string, string | number>;
-}
+};
 
-export interface CenterButtonElement {
+export type CenterButtonElement = {
   disabled: (params: MenuElementParams) => boolean;
   action: (params: MenuElementParams) => void;
-}
+};
 
 export const COLORS = {
   build: "#ebe250",
@@ -566,8 +566,7 @@ export const rootMenuElement: MenuElement = {
 
     const tileOwner = params.game.owner(params.tile);
     const isOwnTerritory =
-      tileOwner.isPlayer() &&
-      (tileOwner as PlayerView).id() === params.myPlayer.id();
+      tileOwner.isPlayer() && tileOwner.id() === params.myPlayer.id();
 
     const menuItems: (MenuElement | null)[] = [
       infoMenuElement,
diff --git a/src/client/graphics/layers/RailroadLayer.ts b/src/client/graphics/layers/RailroadLayer.ts
index 1a77cb77a..8d111b93e 100644
--- a/src/client/graphics/layers/RailroadLayer.ts
+++ b/src/client/graphics/layers/RailroadLayer.ts
@@ -8,7 +8,7 @@ import {
   RailTile,
   RailType,
 } from "../../../core/game/GameUpdates";
-import { GameView, PlayerView } from "../../../core/game/GameView";
+import { GameView } from "../../../core/game/GameView";
 import { Layer } from "./Layer";
 import { getRailroadRects } from "./RailroadSprites";
 
@@ -151,7 +151,7 @@ export class RailroadLayer implements Layer {
     const x = this.game.x(railRoad.tile);
     const y = this.game.y(railRoad.tile);
     const owner = this.game.owner(railRoad.tile);
-    const recipient = owner.isPlayer() ? (owner as PlayerView) : null;
+    const recipient = owner.isPlayer() ? owner : null;
     const color = recipient
       ? this.theme.railroadColor(recipient)
       : new Colord({ r: 255, g: 255, b: 255, a: 1 });
diff --git a/src/client/graphics/layers/ReplayPanel.ts b/src/client/graphics/layers/ReplayPanel.ts
index e68288596..a2fad7bba 100644
--- a/src/client/graphics/layers/ReplayPanel.ts
+++ b/src/client/graphics/layers/ReplayPanel.ts
@@ -12,8 +12,8 @@ import { Layer } from "./Layer";
 
 export class ShowReplayPanelEvent {
   constructor(
-    public visible: boolean = true,
-    public isSingleplayer: boolean = false,
+    public visible = true,
+    public isSingleplayer = false,
   ) {}
 }
 
@@ -23,7 +23,7 @@ export class ReplayPanel extends LitElement implements Layer {
   public eventBus: EventBus | undefined;
 
   @property({ type: Boolean })
-  visible: boolean = false;
+  visible = false;
 
   @state()
   private _replaySpeedMultiplier: number = defaultReplaySpeedMultiplier;
diff --git a/src/client/graphics/layers/SettingsModal.ts b/src/client/graphics/layers/SettingsModal.ts
index 72d4c6cf3..a8e6b359b 100644
--- a/src/client/graphics/layers/SettingsModal.ts
+++ b/src/client/graphics/layers/SettingsModal.ts
@@ -18,9 +18,9 @@ import { Layer } from "./Layer";
 
 export class ShowSettingsModalEvent {
   constructor(
-    public readonly isVisible: boolean = true,
-    public readonly shouldPause: boolean = false,
-    public readonly isPaused: boolean = false,
+    public readonly isVisible = true,
+    public readonly shouldPause = false,
+    public readonly isPaused = false,
   ) {}
 }
 
@@ -30,10 +30,10 @@ export class SettingsModal extends LitElement implements Layer {
   public userSettings: UserSettings;
 
   @state()
-  private isVisible: boolean = false;
+  private isVisible = false;
 
   @state()
-  private alternateView: boolean = false;
+  private alternateView = false;
 
   @query(".modal-overlay")
   private modalOverlay!: HTMLElement;
diff --git a/src/client/graphics/layers/SpawnAd.ts b/src/client/graphics/layers/SpawnAd.ts
index f8f39294f..311d2dcc2 100644
--- a/src/client/graphics/layers/SpawnAd.ts
+++ b/src/client/graphics/layers/SpawnAd.ts
@@ -13,12 +13,12 @@ export class SpawnAd extends LitElement implements Layer {
   public g: GameView;
 
   @state()
-  private isVisible: boolean = false;
+  private isVisible = false;
 
   @state()
-  private adLoaded: boolean = false;
+  private adLoaded = false;
 
-  private gamesPlayed: number = 0;
+  private gamesPlayed = 0;
 
   // Override createRenderRoot to disable shadow DOM
   createRenderRoot() {
diff --git a/src/client/graphics/layers/StructureIconsLayer.ts b/src/client/graphics/layers/StructureIconsLayer.ts
index f28c05a88..83499e0b9 100644
--- a/src/client/graphics/layers/StructureIconsLayer.ts
+++ b/src/client/graphics/layers/StructureIconsLayer.ts
@@ -19,15 +19,15 @@ import { Layer } from "./Layer";
 type ShapeType = "triangle" | "square" | "pentagon" | "octagon" | "circle";
 
 class StructureRenderInfo {
-  public isOnScreen: boolean = false;
+  public isOnScreen = false;
   constructor(
     public unit: UnitView,
     public owner: PlayerID,
     public iconContainer: PIXI.Container,
     public levelContainer: PIXI.Container,
     public dotContainer: PIXI.Container,
-    public level: number = 0,
-    public underConstruction: boolean = true,
+    public level = 0,
+    public underConstruction = true,
   ) {}
 }
 
@@ -58,7 +58,7 @@ export class StructureIconsLayer implements Layer {
   private iconsStage: PIXI.Container;
   private levelsStage: PIXI.Container;
   private dotsStage: PIXI.Container;
-  private shouldRedraw: boolean = true;
+  private shouldRedraw = true;
   private textureCache: Map<string, PIXI.Texture> = new Map();
   private theme: Theme;
   private renderer: PIXI.Renderer;
diff --git a/src/client/graphics/layers/StructureLayer.ts b/src/client/graphics/layers/StructureLayer.ts
index f999edf09..46fe69dc6 100644
--- a/src/client/graphics/layers/StructureLayer.ts
+++ b/src/client/graphics/layers/StructureLayer.ts
@@ -23,11 +23,11 @@ const BASE_TERRITORY_RADIUS = 13.5;
 const RADIUS_SCALE_FACTOR = 0.5;
 const ZOOM_THRESHOLD = 4.3; // below this zoom level, structures are not rendered
 
-interface UnitRenderConfig {
+type UnitRenderConfig = {
   icon: string;
   borderRadius: number;
   territoryRadius: number;
-}
+};
 
 export class StructureLayer implements Layer {
   private canvas: HTMLCanvasElement;
diff --git a/src/client/graphics/layers/TeamStats.ts b/src/client/graphics/layers/TeamStats.ts
index 687d807c6..2a1af49d6 100644
--- a/src/client/graphics/layers/TeamStats.ts
+++ b/src/client/graphics/layers/TeamStats.ts
@@ -6,14 +6,14 @@ import { GameView, PlayerView } from "../../../core/game/GameView";
 import { renderNumber, translateText } from "../../Utils";
 import { Layer } from "./Layer";
 
-interface TeamEntry {
+type TeamEntry = {
   teamName: string;
   totalScoreStr: string;
   totalGold: string;
   totalTroops: string;
   totalScoreSort: number;
   players: PlayerView[];
-}
+};
 
 @customElement("team-stats")
 export class TeamStats extends LitElement implements Layer {
diff --git a/src/client/graphics/layers/TerritoryLayer.ts b/src/client/graphics/layers/TerritoryLayer.ts
index e104559d2..045e5adf2 100644
--- a/src/client/graphics/layers/TerritoryLayer.ts
+++ b/src/client/graphics/layers/TerritoryLayer.ts
@@ -391,7 +391,7 @@ export class TerritoryLayer implements Layer {
     }
   }
 
-  paintTerritory(tile: TileRef, isBorder: boolean = false) {
+  paintTerritory(tile: TileRef, isBorder = false) {
     if (isBorder && !this.game.hasOwner(tile)) {
       return;
     }
diff --git a/src/client/jwt.ts b/src/client/jwt.ts
index c6f6ba381..8b365adf6 100644
--- a/src/client/jwt.ts
+++ b/src/client/jwt.ts
@@ -77,7 +77,7 @@ export function getAuthHeader(): string {
   return `Bearer ${token}`;
 }
 
-export async function logOut(allSessions: boolean = false) {
+export async function logOut(allSessions = false) {
   const token = getToken();
   if (token === null) return;
   clearToken();
diff --git a/src/client/utilities/RenderUnitTypeOptions.ts b/src/client/utilities/RenderUnitTypeOptions.ts
index 0392935d6..725f2bff5 100644
--- a/src/client/utilities/RenderUnitTypeOptions.ts
+++ b/src/client/utilities/RenderUnitTypeOptions.ts
@@ -3,10 +3,10 @@ import { html, TemplateResult } from "lit";
 import { UnitType } from "../../core/game/Game";
 import { translateText } from "../Utils";
 
-export interface UnitTypeRenderContext {
+export type UnitTypeRenderContext = {
   disabledUnits: UnitType[];
   toggleUnit: (unit: UnitType, checked: boolean) => void;
-}
+};
 
 const unitOptions: { type: UnitType; translationKey: string }[] = [
   { type: UnitType.City, translationKey: "unit_type.city" },
diff --git a/src/core/EventBus.ts b/src/core/EventBus.ts
index 008cc7320..3ca0c895b 100644
--- a/src/core/EventBus.ts
+++ b/src/core/EventBus.ts
@@ -1,8 +1,8 @@
 export type GameEvent = object;
 
-export interface EventConstructor<T extends GameEvent = GameEvent> {
-  new (...args: any[]): T;
-}
+export type EventConstructor<T extends GameEvent = GameEvent> = new (
+  ...args: any[]
+) => T;
 
 export class EventBus {
   private listeners: Map<EventConstructor, Array<(event: GameEvent) => void>> =
diff --git a/src/core/GameRunner.ts b/src/core/GameRunner.ts
index 545c73213..9a794aac7 100644
--- a/src/core/GameRunner.ts
+++ b/src/core/GameRunner.ts
@@ -198,7 +198,7 @@ export class GameRunner {
         canTarget: player.canTarget(other),
         sharedBorder: player.sharesBorderWith(other),
       };
-      const alliance = player.allianceWith(other as Player);
+      const alliance = player.allianceWith(other);
       if (alliance) {
         actions.interaction.allianceExpiresAt = alliance.expiresAt();
       }
diff --git a/src/core/PseudoRandom.ts b/src/core/PseudoRandom.ts
index 495796a77..35e092275 100644
--- a/src/core/PseudoRandom.ts
+++ b/src/core/PseudoRandom.ts
@@ -4,9 +4,9 @@ export class PseudoRandom {
   private state1: number;
 
   // Keep these variables to maintain the exact same interface
-  private m: number = 0x80000000; // 2**31
-  private a: number = 1103515245;
-  private c: number = 12345;
+  private m = 0x80000000; // 2**31
+  private a = 1103515245;
+  private c = 12345;
   private state: number;
 
   private static readonly POW36_8 = Math.pow(36, 8); // Pre-compute 36^8
diff --git a/src/core/configuration/Config.ts b/src/core/configuration/Config.ts
index 7dfc9c521..c9b7134e1 100644
--- a/src/core/configuration/Config.ts
+++ b/src/core/configuration/Config.ts
@@ -26,7 +26,7 @@ export enum GameEnv {
   Prod,
 }
 
-export interface ServerConfig {
+export type ServerConfig = {
   turnIntervalMs(): number;
   gameCreationRate(): number;
   lobbyMaxPlayers(
@@ -62,14 +62,14 @@ export interface ServerConfig {
   cloudflareCredsPath(): string;
   stripePublishableKey(): string;
   allowedFlares(): string[] | undefined;
-}
+};
 
-export interface NukeMagnitude {
+export type NukeMagnitude = {
   inner: number;
   outer: number;
-}
+};
 
-export interface Config {
+export type Config = {
   samHittingChance(): number;
   samWarheadHittingChance(): number;
   spawnImmunityDuration(): Tick;
@@ -170,9 +170,9 @@ export interface Config {
   structureMinDist(): number;
   isReplay(): boolean;
   allianceExtensionPromptOffset(): number;
-}
+};
 
-export interface Theme {
+export type Theme = {
   teamColor(team: Team): Colord;
   territoryColor(playerInfo: PlayerView): Colord;
   specialBuildingColor(playerInfo: PlayerView): Colord;
@@ -190,4 +190,4 @@ export interface Theme {
   allyColor(): Colord;
   enemyColor(): Colord;
   spawnHighlightColor(): Colord;
-}
+};
diff --git a/src/core/configuration/ConfigLoader.ts b/src/core/configuration/ConfigLoader.ts
index 7fd65c1d6..3bb7f53fc 100644
--- a/src/core/configuration/ConfigLoader.ts
+++ b/src/core/configuration/ConfigLoader.ts
@@ -12,7 +12,7 @@ export let cachedSC: ServerConfig | null = null;
 export async function getConfig(
   gameConfig: GameConfig,
   userSettings: UserSettings | null,
-  isReplay: boolean = false,
+  isReplay = false,
 ): Promise<Config> {
   const sc = await getServerConfigFromClient();
   switch (sc.env()) {
diff --git a/src/core/execution/AttackExecution.ts b/src/core/execution/AttackExecution.ts
index 69608357a..497cabd0e 100644
--- a/src/core/execution/AttackExecution.ts
+++ b/src/core/execution/AttackExecution.ts
@@ -18,7 +18,7 @@ const malusForRetreat = 25;
 export class AttackExecution implements Execution {
   private breakAlliance = false;
   private wasAlliedAtInit = false; // Store alliance state at initialization
-  private active: boolean = true;
+  private active = true;
   private toConquer = new FlatBinaryHeap();
 
   private random = new PseudoRandom(123);
@@ -34,7 +34,7 @@ export class AttackExecution implements Execution {
     private _owner: Player,
     private _targetID: PlayerID | null,
     private sourceTile: TileRef | null = null,
-    private removeTroops: boolean = true,
+    private removeTroops = true,
   ) {}
 
   public targetID(): PlayerID | null {
@@ -69,7 +69,7 @@ export class AttackExecution implements Execution {
     }
 
     if (this.target && this.target.isPlayer()) {
-      const targetPlayer = this.target as Player;
+      const targetPlayer = this.target;
       if (
         targetPlayer.type() !== PlayerType.Bot &&
         this._owner.type() !== PlayerType.Bot
diff --git a/src/core/execution/CityExecution.ts b/src/core/execution/CityExecution.ts
index c037c12c2..f21e19f62 100644
--- a/src/core/execution/CityExecution.ts
+++ b/src/core/execution/CityExecution.ts
@@ -5,7 +5,7 @@ import { TrainStationExecution } from "./TrainStationExecution";
 export class CityExecution implements Execution {
   private mg: Game;
   private city: Unit | null = null;
-  private active: boolean = true;
+  private active = true;
 
   constructor(
     private player: Player,
@@ -48,7 +48,7 @@ export class CityExecution implements Execution {
   createStation(): void {
     if (this.city !== null) {
       const nearbyFactory = this.mg.hasUnitNearby(
-        this.city.tile()!,
+        this.city.tile(),
         this.mg.config().trainStationMaxRange(),
         UnitType.Factory,
         this.player.id(),
diff --git a/src/core/execution/ConstructionExecution.ts b/src/core/execution/ConstructionExecution.ts
index 8217f497d..772fe7e23 100644
--- a/src/core/execution/ConstructionExecution.ts
+++ b/src/core/execution/ConstructionExecution.ts
@@ -20,7 +20,7 @@ import { WarshipExecution } from "./WarshipExecution";
 
 export class ConstructionExecution implements Execution {
   private construction: Unit | null = null;
-  private active: boolean = true;
+  private active = true;
   private mg: Game;
 
   private ticksUntilComplete: Tick;
diff --git a/src/core/execution/DefensePostExecution.ts b/src/core/execution/DefensePostExecution.ts
index ab36f81ae..40eb9c969 100644
--- a/src/core/execution/DefensePostExecution.ts
+++ b/src/core/execution/DefensePostExecution.ts
@@ -5,7 +5,7 @@ import { ShellExecution } from "./ShellExecution";
 export class DefensePostExecution implements Execution {
   private mg: Game;
   private post: Unit | null = null;
-  private active: boolean = true;
+  private active = true;
 
   private target: Unit | null = null;
   private lastShellAttack = 0;
diff --git a/src/core/execution/DeleteUnitExecution.ts b/src/core/execution/DeleteUnitExecution.ts
index 424130eea..e1291c60b 100644
--- a/src/core/execution/DeleteUnitExecution.ts
+++ b/src/core/execution/DeleteUnitExecution.ts
@@ -1,7 +1,7 @@
 import { Execution, Game, MessageType, Player } from "../game/Game";
 
 export class DeleteUnitExecution implements Execution {
-  private active: boolean = true;
+  private active = true;
   private mg: Game;
 
   constructor(
diff --git a/src/core/execution/FactoryExecution.ts b/src/core/execution/FactoryExecution.ts
index fd24de674..f9065d0ef 100644
--- a/src/core/execution/FactoryExecution.ts
+++ b/src/core/execution/FactoryExecution.ts
@@ -4,7 +4,7 @@ import { TrainStationExecution } from "./TrainStationExecution";
 
 export class FactoryExecution implements Execution {
   private factory: Unit | null = null;
-  private active: boolean = true;
+  private active = true;
   private game: Game;
   constructor(
     private player: Player,
@@ -47,7 +47,7 @@ export class FactoryExecution implements Execution {
   createStation(): void {
     if (this.factory !== null) {
       const structures = this.game.nearbyUnits(
-        this.factory.tile()!,
+        this.factory.tile(),
         this.game.config().trainStationMaxRange(),
         [UnitType.City, UnitType.Port, UnitType.Factory],
       );
diff --git a/src/core/execution/MIRVExecution.ts b/src/core/execution/MIRVExecution.ts
index 9a6075b68..e627fc387 100644
--- a/src/core/execution/MIRVExecution.ts
+++ b/src/core/execution/MIRVExecution.ts
@@ -31,7 +31,7 @@ export class MirvExecution implements Execution {
 
   private separateDst: TileRef;
 
-  private speed: number = -1;
+  private speed = -1;
 
   constructor(
     private player: Player,
diff --git a/src/core/execution/NukeExecution.ts b/src/core/execution/NukeExecution.ts
index 739932a5c..5bfe1debe 100644
--- a/src/core/execution/NukeExecution.ts
+++ b/src/core/execution/NukeExecution.ts
@@ -28,7 +28,7 @@ export class NukeExecution implements Execution {
     private player: Player,
     private dst: TileRef,
     private src?: TileRef | null,
-    private speed: number = -1,
+    private speed = -1,
     private waitTicks = 0,
   ) {}
 
diff --git a/src/core/execution/PlayerExecution.ts b/src/core/execution/PlayerExecution.ts
index db021bd7f..647b97eb2 100644
--- a/src/core/execution/PlayerExecution.ts
+++ b/src/core/execution/PlayerExecution.ts
@@ -28,11 +28,11 @@ export class PlayerExecution implements Execution {
   tick(ticks: number) {
     this.player.decayRelations();
     this.player.units().forEach((u) => {
-      const tileOwner = this.mg!.owner(u.tile());
+      const tileOwner = this.mg.owner(u.tile());
       if (u.info().territoryBound) {
         if (tileOwner.isPlayer()) {
           if (tileOwner !== this.player) {
-            this.mg!.player(tileOwner.id()).captureUnit(u);
+            this.mg.player(tileOwner.id()).captureUnit(u);
           }
         } else {
           u.delete();
@@ -218,7 +218,7 @@ export class PlayerExecution implements Execution {
     }
 
     let largestNeighborAttack: Player | null = null;
-    let largestTroopCount: number = 0;
+    let largestTroopCount = 0;
     for (const id of neighborsIDs) {
       const neighbor = this.mg.playerBySmallID(id);
       if (!neighbor.isPlayer() || this.player.isFriendly(neighbor)) {
diff --git a/src/core/execution/PortExecution.ts b/src/core/execution/PortExecution.ts
index 6d3f45351..1e6bea8e8 100644
--- a/src/core/execution/PortExecution.ts
+++ b/src/core/execution/PortExecution.ts
@@ -90,7 +90,7 @@ export class PortExecution implements Execution {
   createStation(): void {
     if (this.port !== null) {
       const nearbyFactory = this.mg.hasUnitNearby(
-        this.port.tile()!,
+        this.port.tile(),
         this.mg.config().trainStationMaxRange(),
         UnitType.Factory,
         this.player.id(),
diff --git a/src/core/execution/RailroadExecution.ts b/src/core/execution/RailroadExecution.ts
index 97f28f744..268e39ba0 100644
--- a/src/core/execution/RailroadExecution.ts
+++ b/src/core/execution/RailroadExecution.ts
@@ -5,10 +5,10 @@ import { Railroad } from "../game/Railroad";
 
 export class RailroadExecution implements Execution {
   private mg: Game;
-  private active: boolean = true;
-  private headIndex: number = 0;
-  private tailIndex: number = 0;
-  private increment: number = 3;
+  private active = true;
+  private headIndex = 0;
+  private tailIndex = 0;
+  private increment = 3;
   private railTiles: RailTile[] = [];
   constructor(private railRoad: Railroad) {
     this.tailIndex = railRoad.tiles.length;
diff --git a/src/core/execution/SAMLauncherExecution.ts b/src/core/execution/SAMLauncherExecution.ts
index 4fb2765fe..e5467f8f6 100644
--- a/src/core/execution/SAMLauncherExecution.ts
+++ b/src/core/execution/SAMLauncherExecution.ts
@@ -128,7 +128,7 @@ class SAMTargetingSystem {
 
 export class SAMLauncherExecution implements Execution {
   private mg: Game;
-  private active: boolean = true;
+  private active = true;
 
   // As MIRV go very fast we have to detect them very early but we only
   // shoot the one targeting very close (MIRVWarheadProtectionRadius)
diff --git a/src/core/execution/SAMMissileExecution.ts b/src/core/execution/SAMMissileExecution.ts
index e313acd8c..4359d9dc1 100644
--- a/src/core/execution/SAMMissileExecution.ts
+++ b/src/core/execution/SAMMissileExecution.ts
@@ -16,7 +16,7 @@ export class SAMMissileExecution implements Execution {
   private pathFinder: AirPathFinder;
   private SAMMissile: Unit | undefined;
   private mg: Game;
-  private speed: number = 0;
+  private speed = 0;
 
   constructor(
     private spawn: TileRef,
diff --git a/src/core/execution/ShellExecution.ts b/src/core/execution/ShellExecution.ts
index 4bf1103ec..9a05005eb 100644
--- a/src/core/execution/ShellExecution.ts
+++ b/src/core/execution/ShellExecution.ts
@@ -8,7 +8,7 @@ export class ShellExecution implements Execution {
   private pathFinder: AirPathFinder;
   private shell: Unit | undefined;
   private mg: Game;
-  private destroyAtTick: number = -1;
+  private destroyAtTick = -1;
   private random: PseudoRandom;
 
   constructor(
diff --git a/src/core/execution/SpawnExecution.ts b/src/core/execution/SpawnExecution.ts
index 57baff6ee..6721b2794 100644
--- a/src/core/execution/SpawnExecution.ts
+++ b/src/core/execution/SpawnExecution.ts
@@ -5,7 +5,7 @@ import { PlayerExecution } from "./PlayerExecution";
 import { getSpawnTiles } from "./Util";
 
 export class SpawnExecution implements Execution {
-  active: boolean = true;
+  active = true;
   private mg: Game;
 
   constructor(
diff --git a/src/core/execution/TrainExecution.ts b/src/core/execution/TrainExecution.ts
index 34a8634e7..137fa9e88 100644
--- a/src/core/execution/TrainExecution.ts
+++ b/src/core/execution/TrainExecution.ts
@@ -16,13 +16,13 @@ export class TrainExecution implements Execution {
   private mg: Game | null = null;
   private train: Unit | null = null;
   private cars: Unit[] = [];
-  private hasCargo: boolean = false;
-  private currentTile: number = 0;
+  private hasCargo = false;
+  private currentTile = 0;
   private spacing = 2;
   private usedTiles: TileRef[] = []; // used for cars behind
   private stations: TrainStation[] = [];
   private currentRailroad: OrientedRailroad | null = null;
-  private speed: number = 2;
+  private speed = 2;
 
   constructor(
     private railNetwork: RailNetwork,
diff --git a/src/core/execution/TrainStationExecution.ts b/src/core/execution/TrainStationExecution.ts
index ee0174bcc..29792655c 100644
--- a/src/core/execution/TrainStationExecution.ts
+++ b/src/core/execution/TrainStationExecution.ts
@@ -5,12 +5,12 @@ import { TrainExecution } from "./TrainExecution";
 
 export class TrainStationExecution implements Execution {
   private mg: Game;
-  private active: boolean = true;
+  private active = true;
   private random: PseudoRandom;
   private station: TrainStation | null = null;
-  private numCars: number = 5;
-  private lastSpawnTick: number = 0;
-  private ticksCooldown: number = 10; // Minimum cooldown between two trains
+  private numCars = 5;
+  private lastSpawnTick = 0;
+  private ticksCooldown = 10; // Minimum cooldown between two trains
   constructor(
     private unit: Unit,
     private spawnTrains?: boolean, // If set, the station will spawn trains
@@ -50,7 +50,7 @@ export class TrainStationExecution implements Execution {
 
   private shouldSpawnTrain(clusterSize: number): boolean {
     const spawnRate = this.mg.config().trainSpawnRate(clusterSize);
-    for (let i = 0; i < this.unit!.level(); i++) {
+    for (let i = 0; i < this.unit.level(); i++) {
       if (this.random.chance(spawnRate)) {
         return true;
       }
diff --git a/src/core/execution/WarshipExecution.ts b/src/core/execution/WarshipExecution.ts
index 9e0a71309..778a56eed 100644
--- a/src/core/execution/WarshipExecution.ts
+++ b/src/core/execution/WarshipExecution.ts
@@ -79,7 +79,7 @@ export class WarshipExecution implements Execution {
     const patrolRangeSquared = this.mg.config().warshipPatrolRange() ** 2;
 
     const ships = this.mg.nearbyUnits(
-      this.warship.tile()!,
+      this.warship.tile(),
       this.mg.config().warshipTargettingRange(),
       [UnitType.TransportShip, UnitType.Warship, UnitType.TradeShip],
     );
@@ -238,11 +238,11 @@ export class WarshipExecution implements Execution {
     return false;
   }
 
-  randomTile(allowShoreline: boolean = false): TileRef | undefined {
+  randomTile(allowShoreline = false): TileRef | undefined {
     let warshipPatrolRange = this.mg.config().warshipPatrolRange();
-    const maxAttemptBeforeExpand: number = 500;
-    let attempts: number = 0;
-    let expandCount: number = 0;
+    const maxAttemptBeforeExpand = 500;
+    let attempts = 0;
+    let expandCount = 0;
     while (expandCount < 3) {
       const x =
         this.mg.x(this.warship.patrolTile()!) +
diff --git a/src/core/game/AllianceImpl.ts b/src/core/game/AllianceImpl.ts
index fa74ca766..c6b3bb3bc 100644
--- a/src/core/game/AllianceImpl.ts
+++ b/src/core/game/AllianceImpl.ts
@@ -1,8 +1,8 @@
 import { Game, MutableAlliance, Player, Tick } from "./Game";
 
 export class AllianceImpl implements MutableAlliance {
-  private extensionRequestedRequestor_: boolean = false;
-  private extensionRequestedRecipient_: boolean = false;
+  private extensionRequestedRequestor_ = false;
+  private extensionRequestedRecipient_ = false;
 
   private expiresAt_: Tick;
 
diff --git a/src/core/game/BinaryLoaderGameMapLoader.ts b/src/core/game/BinaryLoaderGameMapLoader.ts
index 47dccca7b..bfb6109af 100644
--- a/src/core/game/BinaryLoaderGameMapLoader.ts
+++ b/src/core/game/BinaryLoaderGameMapLoader.ts
@@ -2,13 +2,13 @@ import { GameMapType } from "./Game";
 import { GameMapLoader, MapData } from "./GameMapLoader";
 import { MapManifest } from "./TerrainMapLoader";
 
-export interface BinModule {
+export type BinModule = {
   default: string;
-}
+};
 
-interface NationMapModule {
+type NationMapModule = {
   default: MapManifest;
-}
+};
 
 export class BinaryLoaderGameMapLoader implements GameMapLoader {
   private maps: Map<GameMapType, MapData>;
diff --git a/src/core/game/Game.ts b/src/core/game/Game.ts
index d19134357..105d4dd59 100644
--- a/src/core/game/Game.ts
+++ b/src/core/game/Game.ts
@@ -26,10 +26,10 @@ export type GameUpdates = {
   [K in GameUpdateType]: UpdateTypeMap<K>[];
 };
 
-export interface MapPos {
+export type MapPos = {
   x: number;
   y: number;
-}
+};
 
 export enum Difficulty {
   Easy = "Easy",
@@ -141,7 +141,7 @@ export enum GameMode {
   Team = "Team",
 }
 
-export interface UnitInfo {
+export type UnitInfo = {
   cost: (player: Player) => Gold;
   // Determines if its owner changes when its tile is conquered.
   territoryBound: boolean;
@@ -151,7 +151,7 @@ export interface UnitInfo {
   upgradable?: boolean;
   canBuildTrainStation?: boolean;
   experimental?: boolean;
-}
+};
 
 export enum UnitType {
   TransportShip = "Transport",
@@ -191,15 +191,15 @@ export function isStructureType(type: UnitType): boolean {
   return _structureTypes.has(type);
 }
 
-export interface OwnerComp {
+export type OwnerComp = {
   owner: Player;
-}
+};
 
 export type TrajectoryTile = {
   tile: TileRef;
   targetable: boolean;
 };
-export interface UnitParamsMap {
+export type UnitParamsMap = {
   [UnitType.TransportShip]: {
     troops?: number;
     destination?: TileRef;
@@ -253,7 +253,7 @@ export interface UnitParamsMap {
   };
 
   [UnitType.Construction]: Record<string, never>;
-}
+};
 
 // Type helper to get params type for a specific unit type
 export type UnitParams<T extends UnitType> = UnitParamsMap[T];
@@ -320,14 +320,14 @@ export enum PlayerType {
   FakeHuman = "FAKEHUMAN",
 }
 
-export interface Execution {
+export type Execution = {
   isActive(): boolean;
   activeDuringSpawnPhase(): boolean;
   init(mg: Game, ticks: number): void;
   tick(ticks: number): void;
-}
+};
 
-export interface Attack {
+export type Attack = {
   id(): string;
   retreating(): boolean;
   retreated(): boolean;
@@ -346,25 +346,25 @@ export interface Attack {
   clearBorder(): void;
   borderSize(): number;
   averagePosition(): Cell | null;
-}
+};
 
-export interface AllianceRequest {
+export type AllianceRequest = {
   accept(): void;
   reject(): void;
   requestor(): Player;
   recipient(): Player;
   createdAt(): Tick;
-}
+};
 
-export interface Alliance {
+export type Alliance = {
   requestor(): Player;
   recipient(): Player;
   createdAt(): Tick;
   expiresAt(): Tick;
   other(player: Player): Player;
-}
+};
 
-export interface MutableAlliance extends Alliance {
+export type MutableAlliance = {
   expire(): void;
   other(player: Player): Player;
   bothAgreedToExtend(): boolean;
@@ -372,7 +372,7 @@ export interface MutableAlliance extends Alliance {
   id(): number;
   extend(): void;
   onlyOneAgreedToExtend(): boolean;
-}
+} & Alliance;
 
 export class PlayerInfo {
   public readonly clan: string | null;
@@ -406,7 +406,7 @@ export function isUnit(unit: unknown): unit is Unit {
   );
 }
 
-export interface Unit {
+export type Unit = {
   isUnit(): this is Unit;
 
   // Common properties.
@@ -480,22 +480,22 @@ export interface Unit {
   // Warships
   setPatrolTile(tile: TileRef): void;
   patrolTile(): TileRef | undefined;
-}
+};
 
-export interface TerraNullius {
+export type TerraNullius = {
   isPlayer(): false;
   id(): null;
   clientID(): ClientID;
   smallID(): number;
-}
+};
 
-export interface Embargo {
+export type Embargo = {
   createdAt: Tick;
   isTemporary: boolean;
   target: PlayerID;
-}
+};
 
-export interface Player {
+export type Player = {
   // Basic Info
   smallID(): number;
   info(): PlayerInfo;
@@ -629,9 +629,9 @@ export interface Player {
   tradingPorts(port: Unit): Unit[];
   // WARNING: this operation is expensive.
   bestTransportShipSpawn(tile: TileRef): TileRef | false;
-}
+};
 
-export interface Game extends GameMap {
+export type Game = {
   // Map & Dimensions
   isOnMap(cell: Cell): boolean;
   width(): number;
@@ -715,33 +715,33 @@ export interface Game extends GameMap {
   addUpdate(update: GameUpdate): void;
   railNetwork(): RailNetwork;
   conquerPlayer(conqueror: Player, conquered: Player): void;
-}
+} & GameMap;
 
-export interface PlayerActions {
+export type PlayerActions = {
   canAttack: boolean;
   buildableUnits: BuildableUnit[];
   canSendEmojiAllPlayers: boolean;
   interaction?: PlayerInteraction;
-}
+};
 
-export interface BuildableUnit {
+export type BuildableUnit = {
   canBuild: TileRef | false;
   // unit id of the existing unit that can be upgraded, or false if it cannot be upgraded.
   canUpgrade: number | false;
   type: UnitType;
   cost: Gold;
-}
+};
 
-export interface PlayerProfile {
+export type PlayerProfile = {
   relations: Record<number, Relation>;
   alliances: number[];
-}
+};
 
-export interface PlayerBorderTiles {
+export type PlayerBorderTiles = {
   borderTiles: ReadonlySet<TileRef>;
-}
+};
 
-export interface PlayerInteraction {
+export type PlayerInteraction = {
   sharedBorder: boolean;
   canSendEmoji: boolean;
   canSendAllianceRequest: boolean;
@@ -751,14 +751,14 @@ export interface PlayerInteraction {
   canDonateTroops: boolean;
   canEmbargo: boolean;
   allianceExpiresAt?: Tick;
-}
+};
 
-export interface EmojiMessage {
+export type EmojiMessage = {
   message: string;
   senderID: number;
   recipientID: number | typeof AllPlayers;
   createdAt: Tick;
-}
+};
 
 export enum MessageType {
   ATTACK_FAILED,
@@ -832,8 +832,8 @@ export function getMessageCategory(messageType: MessageType): MessageCategory {
   return MESSAGE_TYPE_CATEGORIES[messageType];
 }
 
-export interface NameViewData {
+export type NameViewData = {
   x: number;
   y: number;
   size: number;
-}
+};
diff --git a/src/core/game/GameImpl.ts b/src/core/game/GameImpl.ts
index 02ec95eb5..5edf2968c 100644
--- a/src/core/game/GameImpl.ts
+++ b/src/core/game/GameImpl.ts
@@ -82,7 +82,7 @@ export class GameImpl implements Game {
   private _railNetwork: RailNetwork = createRailNetwork(this);
 
   // Used to assign unique IDs to each new alliance
-  private nextAllianceID: number = 0;
+  private nextAllianceID = 0;
 
   constructor(
     private _humans: PlayerInfo[],
diff --git a/src/core/game/GameMap.ts b/src/core/game/GameMap.ts
index 7a3bd8e6d..230d52c3a 100644
--- a/src/core/game/GameMap.ts
+++ b/src/core/game/GameMap.ts
@@ -3,7 +3,7 @@ import { Cell, TerrainType } from "./Game";
 export type TileRef = number;
 export type TileUpdate = bigint;
 
-export interface GameMap {
+export type GameMap = {
   ref(x: number, y: number): TileRef;
   isValidRef(ref: TileRef): boolean;
   x(ref: TileRef): number;
@@ -48,7 +48,7 @@ export interface GameMap {
   updateTile(tu: TileUpdate): TileRef;
 
   numTilesWithFallout(): number;
-}
+};
 
 export class GameMapImpl implements GameMap {
   private _numTilesWithFallout = 0;
@@ -341,7 +341,7 @@ export class GameMapImpl implements GameMap {
 export function euclDistFN(
   root: TileRef,
   dist: number,
-  center: boolean = false,
+  center = false,
 ): (gm: GameMap, tile: TileRef) => boolean {
   const dist2 = dist * dist;
   if (!center) {
@@ -364,7 +364,7 @@ export function euclDistFN(
 export function manhattanDistFN(
   root: TileRef,
   dist: number,
-  center: boolean = false,
+  center = false,
 ): (gm: GameMap, tile: TileRef) => boolean {
   if (!center) {
     return (gm: GameMap, n: TileRef) => gm.manhattanDist(root, n) <= dist;
@@ -382,7 +382,7 @@ export function manhattanDistFN(
 export function rectDistFN(
   root: TileRef,
   dist: number,
-  center: boolean = false,
+  center = false,
 ): (gm: GameMap, tile: TileRef) => boolean {
   if (!center) {
     return (gm: GameMap, n: TileRef) => {
@@ -415,7 +415,7 @@ function isInIsometricTile(
 export function isometricDistFN(
   root: TileRef,
   dist: number,
-  center: boolean = false,
+  center = false,
 ): (gm: GameMap, tile: TileRef) => boolean {
   if (!center) {
     return (gm: GameMap, n: TileRef) => gm.manhattanDist(root, n) <= dist;
@@ -437,7 +437,7 @@ export function isometricDistFN(
 export function hexDistFN(
   root: TileRef,
   dist: number,
-  center: boolean = false,
+  center = false,
 ): (gm: GameMap, tile: TileRef) => boolean {
   if (!center) {
     return (gm: GameMap, n: TileRef) => {
diff --git a/src/core/game/GameMapLoader.ts b/src/core/game/GameMapLoader.ts
index abf52ccf9..dd9d378c5 100644
--- a/src/core/game/GameMapLoader.ts
+++ b/src/core/game/GameMapLoader.ts
@@ -1,13 +1,13 @@
 import { GameMapType } from "./Game";
 import { MapManifest } from "./TerrainMapLoader";
 
-export interface GameMapLoader {
+export type GameMapLoader = {
   getMapData(map: GameMapType): MapData;
-}
+};
 
-export interface MapData {
+export type MapData = {
   mapBin: () => Promise<Uint8Array>;
   miniMapBin: () => Promise<Uint8Array>;
   manifest: () => Promise<MapManifest>;
   webpPath: () => Promise<string>;
-}
+};
diff --git a/src/core/game/GameUpdates.ts b/src/core/game/GameUpdates.ts
index 565960479..cf60babac 100644
--- a/src/core/game/GameUpdates.ts
+++ b/src/core/game/GameUpdates.ts
@@ -14,17 +14,17 @@ import {
 } from "./Game";
 import { TileRef, TileUpdate } from "./GameMap";
 
-export interface GameUpdateViewData {
+export type GameUpdateViewData = {
   tick: number;
   updates: GameUpdates;
   packedTileUpdates: BigUint64Array;
   playerNameViewData: Record<string, NameViewData>;
-}
+};
 
-export interface ErrorUpdate {
+export type ErrorUpdate = {
   errMsg: string;
   stack?: string;
-}
+};
 
 export enum GameUpdateType {
   Tile,
@@ -67,13 +67,13 @@ export type GameUpdate =
   | RailroadUpdate
   | ConquestUpdate;
 
-export interface BonusEventUpdate {
+export type BonusEventUpdate = {
   type: GameUpdateType.BonusEvent;
   player: PlayerID;
   tile: TileRef;
   gold: number;
   troops: number;
-}
+};
 
 export enum RailType {
   VERTICAL,
@@ -84,30 +84,30 @@ export enum RailType {
   BOTTOM_RIGHT,
 }
 
-export interface RailTile {
+export type RailTile = {
   tile: TileRef;
   railType: RailType;
-}
+};
 
-export interface RailroadUpdate {
+export type RailroadUpdate = {
   type: GameUpdateType.RailroadEvent;
   isActive: boolean;
   railTiles: RailTile[];
-}
+};
 
-export interface ConquestUpdate {
+export type ConquestUpdate = {
   type: GameUpdateType.ConquestEvent;
   conquerorId: PlayerID;
   conqueredId: PlayerID;
   gold: Gold;
-}
+};
 
-export interface TileUpdateWrapper {
+export type TileUpdateWrapper = {
   type: GameUpdateType.Tile;
   update: TileUpdate;
-}
+};
 
-export interface UnitUpdate {
+export type UnitUpdate = {
   type: GameUpdateType.Unit;
   unitType: UnitType;
   troops: number;
@@ -130,17 +130,17 @@ export interface UnitUpdate {
   hasTrainStation: boolean;
   trainType?: TrainType; // Only for trains
   loaded?: boolean; // Only for trains
-}
+};
 
-export interface AttackUpdate {
+export type AttackUpdate = {
   attackerID: number;
   targetID: number;
   troops: number;
   id: string;
   retreating: boolean;
-}
+};
 
-export interface PlayerUpdate {
+export type PlayerUpdate = {
   type: GameUpdateType.Player;
   nameViewData?: NameViewData;
   clientID: ClientID | null;
@@ -166,65 +166,65 @@ export interface PlayerUpdate {
   alliances: AllianceView[];
   hasSpawned: boolean;
   betrayals?: bigint;
-}
+};
 
-export interface AllianceView {
+export type AllianceView = {
   id: number;
   other: PlayerID;
   createdAt: Tick;
   expiresAt: Tick;
-}
+};
 
-export interface AllianceRequestUpdate {
+export type AllianceRequestUpdate = {
   type: GameUpdateType.AllianceRequest;
   requestorID: number;
   recipientID: number;
   createdAt: Tick;
-}
+};
 
-export interface AllianceRequestReplyUpdate {
+export type AllianceRequestReplyUpdate = {
   type: GameUpdateType.AllianceRequestReply;
   request: AllianceRequestUpdate;
   accepted: boolean;
-}
+};
 
-export interface BrokeAllianceUpdate {
+export type BrokeAllianceUpdate = {
   type: GameUpdateType.BrokeAlliance;
   traitorID: number;
   betrayedID: number;
-}
+};
 
-export interface AllianceExpiredUpdate {
+export type AllianceExpiredUpdate = {
   type: GameUpdateType.AllianceExpired;
   player1ID: number;
   player2ID: number;
-}
+};
 
-export interface AllianceExtensionUpdate {
+export type AllianceExtensionUpdate = {
   type: GameUpdateType.AllianceExtension;
   playerID: number;
   allianceID: number;
-}
+};
 
-export interface TargetPlayerUpdate {
+export type TargetPlayerUpdate = {
   type: GameUpdateType.TargetPlayer;
   playerID: number;
   targetID: number;
-}
+};
 
-export interface EmojiUpdate {
+export type EmojiUpdate = {
   type: GameUpdateType.Emoji;
   emoji: EmojiMessage;
-}
+};
 
-export interface DisplayMessageUpdate {
+export type DisplayMessageUpdate = {
   type: GameUpdateType.DisplayEvent;
   message: string;
   messageType: MessageType;
   goldAmount?: bigint;
   playerID: number | null;
   params?: Record<string, string | number>;
-}
+};
 
 export type DisplayChatMessageUpdate = {
   type: GameUpdateType.DisplayChatEvent;
@@ -236,22 +236,22 @@ export type DisplayChatMessageUpdate = {
   recipient: string;
 };
 
-export interface WinUpdate {
+export type WinUpdate = {
   type: GameUpdateType.Win;
   allPlayersStats: AllPlayersStats;
   winner: Winner;
-}
+};
 
-export interface HashUpdate {
+export type HashUpdate = {
   type: GameUpdateType.Hash;
   tick: Tick;
   hash: number;
-}
+};
 
-export interface UnitIncomingUpdate {
+export type UnitIncomingUpdate = {
   type: GameUpdateType.UnitIncoming;
   unitID: number;
   message: string;
   messageType: MessageType;
   playerID: number;
-}
+};
diff --git a/src/core/game/GameView.ts b/src/core/game/GameView.ts
index 34dc7e005..2739cda60 100644
--- a/src/core/game/GameView.ts
+++ b/src/core/game/GameView.ts
@@ -39,10 +39,10 @@ import { UserSettings } from "./UserSettings";
 
 const userSettings: UserSettings = new UserSettings();
 
-interface PlayerCosmetics {
+type PlayerCosmetics = {
   pattern?: string | undefined;
   flag?: string | undefined;
-}
+};
 
 export class UnitView {
   public _wasUpdated = true;
@@ -106,7 +106,7 @@ export class UnitView {
     return this.data.pos;
   }
   owner(): PlayerView {
-    return this.gameView.playerBySmallID(this.data.ownerID)! as PlayerView;
+    return this.gameView.playerBySmallID(this.data.ownerID) as PlayerView;
   }
   isActive(): boolean {
     return this.data.isActive;
diff --git a/src/core/game/PlayerImpl.ts b/src/core/game/PlayerImpl.ts
index 56a88cc6f..7924e4605 100644
--- a/src/core/game/PlayerImpl.ts
+++ b/src/core/game/PlayerImpl.ts
@@ -53,10 +53,10 @@ import {
 } from "./TransportShipUtils";
 import { UnitImpl } from "./UnitImpl";
 
-interface Target {
+type Target = {
   tick: Tick;
   target: Player;
-}
+};
 
 class Donation {
   constructor(
@@ -66,7 +66,7 @@ class Donation {
 }
 
 export class PlayerImpl implements Player {
-  public _lastTileChange: number = 0;
+  public _lastTileChange = 0;
   public _pseudo_random: PseudoRandom;
 
   private _gold: bigint;
@@ -278,7 +278,7 @@ export class PlayerImpl implements Player {
   }
 
   tiles(): ReadonlySet<TileRef> {
-    return new Set(this._tiles.values()) as Set<TileRef>;
+    return new Set(this._tiles.values());
   }
 
   borderTiles(): ReadonlySet<TileRef> {
diff --git a/src/core/game/RailNetwork.ts b/src/core/game/RailNetwork.ts
index 404c062be..00c2e6f5e 100644
--- a/src/core/game/RailNetwork.ts
+++ b/src/core/game/RailNetwork.ts
@@ -1,8 +1,8 @@
 import { Unit } from "./Game";
 import { TrainStation } from "./TrainStation";
 
-export interface RailNetwork {
+export type RailNetwork = {
   connectStation(station: TrainStation): void;
   removeStation(unit: Unit): void;
   findStationsPath(from: TrainStation, to: TrainStation): TrainStation[];
-}
+};
diff --git a/src/core/game/RailNetworkImpl.ts b/src/core/game/RailNetworkImpl.ts
index 4d054f911..6232ba06d 100644
--- a/src/core/game/RailNetworkImpl.ts
+++ b/src/core/game/RailNetworkImpl.ts
@@ -13,12 +13,12 @@ import { Cluster, TrainStation, TrainStationMapAdapter } from "./TrainStation";
  * but it would be expensive to look through the graph to find a station.
  * This class stores the existing stations for quick access
  */
-export interface StationManager {
+export type StationManager = {
   addStation(station: TrainStation): void;
   removeStation(station: TrainStation): void;
   findStation(unit: Unit): TrainStation | null;
   getAll(): Set<TrainStation>;
-}
+};
 
 export class StationManagerImpl implements StationManager {
   private stations: Set<TrainStation> = new Set();
@@ -43,10 +43,10 @@ export class StationManagerImpl implements StationManager {
   }
 }
 
-export interface RailPathFinderService {
+export type RailPathFinderService = {
   findTilePath(from: TileRef, to: TileRef): TileRef[];
   findStationsPath(from: TrainStation, to: TrainStation): TrainStation[];
-}
+};
 
 class RailPathFinderServiceImpl implements RailPathFinderService {
   constructor(private game: Game) {}
@@ -88,7 +88,7 @@ export function createRailNetwork(game: Game): RailNetwork {
 }
 
 export class RailNetworkImpl implements RailNetwork {
-  private maxConnectionDistance: number = 4;
+  private maxConnectionDistance = 4;
 
   constructor(
     private game: Game,
diff --git a/src/core/game/Stats.ts b/src/core/game/Stats.ts
index d328c6d71..63a8aac79 100644
--- a/src/core/game/Stats.ts
+++ b/src/core/game/Stats.ts
@@ -2,7 +2,7 @@ import { AllPlayersStats } from "../Schemas";
 import { NukeType, OtherUnitType, PlayerStats } from "../StatsSchemas";
 import { Player, TerraNullius } from "./Game";
 
-export interface Stats {
+export type Stats = {
   getPlayerStats(player: Player): PlayerStats | null;
   stats(): AllPlayersStats;
 
@@ -93,4 +93,4 @@ export interface Stats {
 
   // Player loses a unit of type
   unitLose(player: Player, type: OtherUnitType): void;
-}
+};
diff --git a/src/core/game/TrainStation.ts b/src/core/game/TrainStation.ts
index 458ba2785..55e74ff49 100644
--- a/src/core/game/TrainStation.ts
+++ b/src/core/game/TrainStation.ts
@@ -9,16 +9,16 @@ import { Railroad } from "./Railroad";
 /**
  * Handle train stops at various station types
  */
-interface TrainStopHandler {
+type TrainStopHandler = {
   onStop(mg: Game, station: TrainStation, trainExecution: TrainExecution): void;
-}
+};
 
 /**
  * All stop handlers share the same logic for the time being
  * Behavior to be defined
  */
 class CityStopHandler implements TrainStopHandler {
-  private factor: bigint = BigInt(2);
+  private factor = BigInt(2);
   onStop(
     mg: Game,
     station: TrainStation,
@@ -38,7 +38,7 @@ class CityStopHandler implements TrainStopHandler {
 }
 
 class PortStopHandler implements TrainStopHandler {
-  private factor: bigint = BigInt(2);
+  private factor = BigInt(2);
   constructor(private random: PseudoRandom) {}
   onStop(
     mg: Game,
@@ -59,7 +59,7 @@ class PortStopHandler implements TrainStopHandler {
 }
 
 class FactoryStopHandler implements TrainStopHandler {
-  private factor: bigint = BigInt(2);
+  private factor = BigInt(2);
   onStop(
     mg: Game,
     station: TrainStation,
diff --git a/src/core/game/TransportShipUtils.ts b/src/core/game/TransportShipUtils.ts
index 0e22eafdd..df335b714 100644
--- a/src/core/game/TransportShipUtils.ts
+++ b/src/core/game/TransportShipUtils.ts
@@ -102,7 +102,7 @@ export function sourceDstOceanShore(
   const srcTile = closestShoreFromPlayer(gm, src, tile);
   let dstTile: TileRef | null = null;
   if (dst.isPlayer()) {
-    dstTile = closestShoreFromPlayer(gm, dst as Player, tile);
+    dstTile = closestShoreFromPlayer(gm, dst, tile);
   } else {
     dstTile = closestShoreTN(gm, tile, 50);
   }
@@ -113,7 +113,7 @@ export function targetTransportTile(gm: Game, tile: TileRef): TileRef | null {
   const dst = gm.playerBySmallID(gm.ownerID(tile));
   let dstTile: TileRef | null = null;
   if (dst.isPlayer()) {
-    dstTile = closestShoreFromPlayer(gm, dst as Player, tile);
+    dstTile = closestShoreFromPlayer(gm, dst, tile);
   } else {
     dstTile = closestShoreTN(gm, tile, 50);
   }
@@ -235,7 +235,7 @@ export function candidateShoreTiles(
     extremumTiles.maxX,
     extremumTiles.maxY,
     ...sampledTiles,
-  ].filter(Boolean) as number[];
+  ].filter(Boolean);
 
   return candidates;
 }
diff --git a/src/core/game/UnitImpl.ts b/src/core/game/UnitImpl.ts
index c9c61b562..c30403108 100644
--- a/src/core/game/UnitImpl.ts
+++ b/src/core/game/UnitImpl.ts
@@ -21,7 +21,7 @@ export class UnitImpl implements Unit {
   private _targetUnit: Unit | undefined;
   private _health: bigint;
   private _lastTile: TileRef;
-  private _retreating: boolean = false;
+  private _retreating = false;
   private _targetedBySAM = false;
   private _reachedTarget = false;
   private _lastSetSafeFromPirates: number; // Only for trade ships
@@ -30,14 +30,14 @@ export class UnitImpl implements Unit {
   private _troops: number;
   // Number of missiles in cooldown, if empty all missiles are ready.
   private _missileTimerQueue: number[] = [];
-  private _hasTrainStation: boolean = false;
+  private _hasTrainStation = false;
   private _patrolTile: TileRef | undefined;
-  private _level: number = 1;
-  private _targetable: boolean = true;
+  private _level = 1;
+  private _targetable = true;
   private _loaded: boolean | undefined;
   private _trainType: TrainType | undefined;
   // Nuke only
-  private _trajectoryIndex: number = 0;
+  private _trajectoryIndex = 0;
   private _trajectory: TrajectoryTile[];
 
   constructor(
diff --git a/src/core/pathfinding/AStar.ts b/src/core/pathfinding/AStar.ts
index f16accf4e..4056c684f 100644
--- a/src/core/pathfinding/AStar.ts
+++ b/src/core/pathfinding/AStar.ts
@@ -1,7 +1,7 @@
-export interface AStar<NodeType> {
+export type AStar<NodeType> = {
   compute(): PathFindResultType;
   reconstructPath(): NodeType[];
-}
+};
 
 export enum PathFindResultType {
   NextTile,
@@ -25,7 +25,7 @@ export type AStarResult<NodeType> =
       type: PathFindResultType.PathNotFound;
     };
 
-export interface Point {
+export type Point = {
   x: number;
   y: number;
-}
+};
diff --git a/src/core/pathfinding/MiniAStar.ts b/src/core/pathfinding/MiniAStar.ts
index a355afd41..2c43950cb 100644
--- a/src/core/pathfinding/MiniAStar.ts
+++ b/src/core/pathfinding/MiniAStar.ts
@@ -36,8 +36,8 @@ export class MiniAStar implements AStar<TileRef> {
     private dst: TileRef,
     iterations: number,
     maxTries: number,
-    waterPath: boolean = true,
-    directionChangePenalty: number = 0,
+    waterPath = true,
+    directionChangePenalty = 0,
   ) {
     const srcArray: TileRef[] = Array.isArray(src) ? src : [src];
     const miniSrc = srcArray.map((srcPoint) =>
@@ -113,7 +113,7 @@ function fixExtremes(upscaled: Cell[], cellDst: Cell, cellSrc?: Cell): Cell[] {
   return upscaled;
 }
 
-function upscalePath(path: Cell[], scaleFactor: number = 2): Cell[] {
+function upscalePath(path: Cell[], scaleFactor = 2): Cell[] {
   // Scale up each point
   const scaledPath = path.map(
     (point) => new Cell(point.x * scaleFactor, point.y * scaleFactor),
diff --git a/src/core/pathfinding/PathFinding.ts b/src/core/pathfinding/PathFinding.ts
index 9a34e3316..d5723abf1 100644
--- a/src/core/pathfinding/PathFinding.ts
+++ b/src/core/pathfinding/PathFinding.ts
@@ -14,7 +14,7 @@ export class ParabolaPathFinder {
   computeControlPoints(
     orig: TileRef,
     dst: TileRef,
-    increment: number = 3,
+    increment = 3,
     distanceBasedHeight = true,
   ) {
     const p0 = { x: this.mg.x(orig), y: this.mg.y(orig) };
@@ -117,8 +117,8 @@ export class PathFinder {
   public static Mini(
     game: Game,
     iterations: number,
-    waterPath: boolean = true,
-    maxTries: number = 20,
+    waterPath = true,
+    maxTries = 20,
   ) {
     return new PathFinder(game, (curr: TileRef, dst: TileRef) => {
       return new MiniAStar(
@@ -136,7 +136,7 @@ export class PathFinder {
   nextTile(
     curr: TileRef | null,
     dst: TileRef | null,
-    dist: number = 1,
+    dist = 1,
   ): AStarResult<TileRef> {
     if (curr === null) {
       console.error("curr is null");
diff --git a/src/core/pathfinding/SerialAStar.ts b/src/core/pathfinding/SerialAStar.ts
index fdb138c82..eef9306c4 100644
--- a/src/core/pathfinding/SerialAStar.ts
+++ b/src/core/pathfinding/SerialAStar.ts
@@ -4,12 +4,12 @@ import { AStar, PathFindResultType } from "./AStar";
 /**
  * Implement this interface with your graph to find paths with A*
  */
-export interface GraphAdapter<NodeType> {
+export type GraphAdapter<NodeType> = {
   neighbors(node: NodeType): NodeType[];
   cost(node: NodeType): number;
   position(node: NodeType): { x: number; y: number };
   isTraversable(from: NodeType, to: NodeType): boolean;
-}
+};
 
 export class SerialAStar<NodeType> implements AStar<NodeType> {
   private fwdOpenSet: FastPriorityQueue<{
@@ -37,7 +37,7 @@ export class SerialAStar<NodeType> implements AStar<NodeType> {
     private iterations: number,
     private maxTries: number,
     private graph: GraphAdapter<NodeType>,
-    private directionChangePenalty: number = 0,
+    private directionChangePenalty = 0,
   ) {
     this.fwdOpenSet = new FastPriorityQueue((a, b) => a.fScore < b.fScore);
     this.bwdOpenSet = new FastPriorityQueue((a, b) => a.fScore < b.fScore);
diff --git a/src/core/utilities/Line.ts b/src/core/utilities/Line.ts
index 67024e9c6..57aea1e6c 100644
--- a/src/core/utilities/Line.ts
+++ b/src/core/utilities/Line.ts
@@ -77,9 +77,9 @@ export class CubicBezierCurve {
  *  Useful to compute regular steps based on the curve rather than a t
  */
 export class DistanceBasedBezierCurve extends CubicBezierCurve {
-  private totalDistance: number = 0;
+  private totalDistance = 0;
   private cachedPoints: Point[] = [];
-  private currentIndex: number = 0;
+  private currentIndex = 0;
 
   constructor(
     p0: Point,
diff --git a/src/core/worker/WorkerMessages.ts b/src/core/worker/WorkerMessages.ts
index 65234e2f6..059fbe3f7 100644
--- a/src/core/worker/WorkerMessages.ts
+++ b/src/core/worker/WorkerMessages.ts
@@ -26,91 +26,91 @@ export type WorkerMessageType =
   | "transport_ship_spawn_result";
 
 // Base interface for all messages
-interface BaseWorkerMessage {
+type BaseWorkerMessage = {
   type: WorkerMessageType;
   id?: string;
-}
+};
 
-export interface HeartbeatMessage extends BaseWorkerMessage {
+export type HeartbeatMessage = {
   type: "heartbeat";
-}
+} & BaseWorkerMessage;
 
 // Messages from main thread to worker
-export interface InitMessage extends BaseWorkerMessage {
+export type InitMessage = {
   type: "init";
   gameStartInfo: GameStartInfo;
   clientID: ClientID;
-}
+} & BaseWorkerMessage;
 
-export interface TurnMessage extends BaseWorkerMessage {
+export type TurnMessage = {
   type: "turn";
   turn: Turn;
-}
+} & BaseWorkerMessage;
 
 // Messages from worker to main thread
-export interface InitializedMessage extends BaseWorkerMessage {
+export type InitializedMessage = {
   type: "initialized";
-}
+} & BaseWorkerMessage;
 
-export interface GameUpdateMessage extends BaseWorkerMessage {
+export type GameUpdateMessage = {
   type: "game_update";
   gameUpdate: GameUpdateViewData;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerActionsMessage extends BaseWorkerMessage {
+export type PlayerActionsMessage = {
   type: "player_actions";
   playerID: PlayerID;
   x: number;
   y: number;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerActionsResultMessage extends BaseWorkerMessage {
+export type PlayerActionsResultMessage = {
   type: "player_actions_result";
   result: PlayerActions;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerProfileMessage extends BaseWorkerMessage {
+export type PlayerProfileMessage = {
   type: "player_profile";
   playerID: number;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerProfileResultMessage extends BaseWorkerMessage {
+export type PlayerProfileResultMessage = {
   type: "player_profile_result";
   result: PlayerProfile;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerBorderTilesMessage extends BaseWorkerMessage {
+export type PlayerBorderTilesMessage = {
   type: "player_border_tiles";
   playerID: PlayerID;
-}
+} & BaseWorkerMessage;
 
-export interface PlayerBorderTilesResultMessage extends BaseWorkerMessage {
+export type PlayerBorderTilesResultMessage = {
   type: "player_border_tiles_result";
   result: PlayerBorderTiles;
-}
+} & BaseWorkerMessage;
 
-export interface AttackAveragePositionMessage extends BaseWorkerMessage {
+export type AttackAveragePositionMessage = {
   type: "attack_average_position";
   playerID: number;
   attackID: string;
-}
+} & BaseWorkerMessage;
 
-export interface AttackAveragePositionResultMessage extends BaseWorkerMessage {
+export type AttackAveragePositionResultMessage = {
   type: "attack_average_position_result";
   x: number | null;
   y: number | null;
-}
+} & BaseWorkerMessage;
 
-export interface TransportShipSpawnMessage extends BaseWorkerMessage {
+export type TransportShipSpawnMessage = {
   type: "transport_ship_spawn";
   playerID: PlayerID;
   targetTile: TileRef;
-}
+} & BaseWorkerMessage;
 
-export interface TransportShipSpawnResultMessage extends BaseWorkerMessage {
+export type TransportShipSpawnResultMessage = {
   type: "transport_ship_spawn_result";
   result: TileRef | false;
-}
+} & BaseWorkerMessage;
 
 // Union types for type safety
 export type MainThreadMessage =
diff --git a/src/server/Cloudflare.ts b/src/server/Cloudflare.ts
index 140e868f6..197c29430 100644
--- a/src/server/Cloudflare.ts
+++ b/src/server/Cloudflare.ts
@@ -8,39 +8,39 @@ const log = logger.child({
   module: "cloudflare",
 });
 
-export interface TunnelConfig {
+export type TunnelConfig = {
   domain: string;
   subdomain: string;
   subdomainToService: Map<string, string>;
-}
+};
 
-interface TunnelResponse {
+type TunnelResponse = {
   result: {
     id: string;
     token: string;
   };
-}
+};
 
-interface ZoneResponse {
+type ZoneResponse = {
   result: Array<{
     id: string;
   }>;
-}
+};
 
-interface DNSRecordResponse {
+type DNSRecordResponse = {
   result: Array<{
     id: string;
   }>;
-}
+};
 
-interface CloudflaredConfig {
+type CloudflaredConfig = {
   tunnel: string;
   "credentials-file": string;
   ingress: Array<{
     hostname?: string;
     service: string;
   }>;
-}
+};
 
 const CloudflareTunnelConfigSchema = z.object({
   a: z.string(),
@@ -63,7 +63,7 @@ export class Cloudflare {
 
   private async makeRequest<T>(
     url: string,
-    method: string = "GET",
+    method = "GET",
     data?: any,
   ): Promise<T> {
     const response = await fetch(url, {
diff --git a/src/server/Gatekeeper.ts b/src/server/Gatekeeper.ts
index ee47cbf50..81d2fd9ff 100644
--- a/src/server/Gatekeeper.ts
+++ b/src/server/Gatekeeper.ts
@@ -12,7 +12,7 @@ export enum LimiterType {
   WebSocket = "websocket",
 }
 
-export interface Gatekeeper {
+export type Gatekeeper = {
   // The wrapper for request handlers with optional rate limiting
   httpHandler: (
     limiterType: LimiterType,
@@ -24,7 +24,7 @@ export interface Gatekeeper {
     req: http.IncomingMessage | string,
     fn: (message: string) => Promise<void>,
   ) => (message: string) => Promise<void>;
-}
+};
 
 let gk: Gatekeeper | null = null;
 
diff --git a/src/server/MapPlaylist.ts b/src/server/MapPlaylist.ts
index 1698bef68..9927289af 100644
--- a/src/server/MapPlaylist.ts
+++ b/src/server/MapPlaylist.ts
@@ -49,10 +49,10 @@ const frequency: Partial<Record<GameMapName, number>> = {
   Yenisei: 1,
 };
 
-interface MapWithMode {
+type MapWithMode = {
   map: GameMapType;
   mode: GameMode;
-}
+};
 
 const TEAM_COUNTS = [
   2,
diff --git a/src/server/Privilege.ts b/src/server/Privilege.ts
index 88908215f..6d7722020 100644
--- a/src/server/Privilege.ts
+++ b/src/server/Privilege.ts
@@ -1,7 +1,7 @@
 import { Cosmetics, Pattern } from "../core/CosmeticSchemas";
 import { PatternDecoder } from "../core/PatternDecoder";
 
-export interface PrivilegeChecker {
+export type PrivilegeChecker = {
   isPatternAllowed(
     base64: string,
     flares: readonly string[] | undefined,
@@ -10,7 +10,7 @@ export interface PrivilegeChecker {
     flag: string,
     flares: readonly string[] | undefined,
   ): true | "restricted" | "invalid";
-}
+};
 
 export class PrivilegeCheckerImpl implements PrivilegeChecker {
   private b64ToPattern: Record<string, Pattern> = {};
diff --git a/tests/util/TestConfig.ts b/tests/util/TestConfig.ts
index f0b10ac37..69b23f3cd 100644
--- a/tests/util/TestConfig.ts
+++ b/tests/util/TestConfig.ts
@@ -10,8 +10,8 @@ import {
 import { TileRef } from "../../src/core/game/GameMap";
 
 export class TestConfig extends DefaultConfig {
-  private _proximityBonusPortsNb: number = 0;
-  private _defaultNukeSpeed: number = 4;
+  private _proximityBonusPortsNb = 0;
+  private _defaultNukeSpeed = 4;
 
   samHittingChance(): number {
     return 1;