diff --git a/server.js b/server.js
index 2ef7d10..c0be258 100644
--- a/server.js
+++ b/server.js
@@ -1,8 +1,8 @@
-const {Board, Piece} = require('./src/backend');
+const { Board } = require('./src/backend');
 
-const express = require("express");
-const http = require("http");
-const socketIo = require("socket.io");
+const express = require('express');
+const http = require('http');
+const socketIo = require('socket.io');
 
 const port = process.env.PORT || 4001;
 
@@ -18,20 +18,15 @@ const io = socketIo(server, {
 
 let interval;
 
-let board = new Board();
-
-let sockets = [];
 let games = new Map();
 
 io.on("connection", (socket) => {
-  sockets.push(socket);
   console.log("New client connected");
   if (interval) {
     clearInterval(interval);
   }
   //interval = setInterval(() => getApiAndEmit(socket), 5000);
   socket.on("disconnect", () => {
-    // TODO sockets.remove(socket)
     console.log("Client disconnected");
     clearInterval(interval);
   });
@@ -58,9 +53,9 @@ io.on("connection", (socket) => {
   socket.on("move", (key, move) => {
     console.log(`Received move at '${key}'`);
     let game = games.get(key);
-    if(move && game.board.makeMove(move.from, move.to) == 0) {
+    if(move && game.board.makeMove(move.from, move.to) === 0) {
       games.set(key, game);
-      for (s of game.sockets) {
+      for (const s of game.sockets) {
         getApiAndEmit(s, game.board);
       }
     }
diff --git a/src/backend.js b/src/backend.js
index 6421a48..b7eb41e 100644
--- a/src/backend.js
+++ b/src/backend.js
@@ -1,3 +1,6 @@
+import { Piece } from './logic'
+
+
 const BLACK = 0; const WHITE = 1;
 
 const PAWN = 0;
@@ -36,71 +39,6 @@ function imageFromPiece(piece) {
   return null;
 }
 
-class Piece {
-  constructor(color, type) {
-    this.color = color;
-    this.type = type;
-    this.passantable = false;
-    this.moves = 0;
-  }
-
-  setType(type) {
-    this.type = type;
-  }
-
-  getInfoText() {
-    if(this.moves === 1) {
-      return "Has made 1 move"
-    } else {
-      return "Has made " + this.moves + " moves"
-    }
-  }
-
-  isEmpty() {
-    return this.type === EMPTY;
-  }
-
-  isFull() {
-    return !this.isEmpty();
-  }
-
-  isBlack() {
-    return this.color === BLACK;
-  }
-
-  isWhite() {
-    return this.color === WHITE;
-  }
-
-  isEnemyOf(piece) {
-    if (this.color === EMPTY || piece.color === EMPTY) {
-      return false;
-    } else {
-      return this.color !== piece.color;
-    }
-  }
-
-  isFriendOf(piece) {
-    if (this.color === EMPTY || piece.color === EMPTY) {
-      return false;
-    } else {
-      return this.color === piece.color;
-    }
-  }
-
-  is(type) {
-    return this.type === type;
-  }
-
-  hasMoved() {
-    return this.moves !== 0;
-  }
-
-  hasntMoved() {
-    return !this.hasMoved();
-  }
-}
-
 class Board {
   constructor(props) {
     this.state = (props && props.text) ?
@@ -190,7 +128,7 @@ class Board {
         default:
           return '_';
       }
-    }).join('');;
+    }).join('');
   }
 
   doReset() {
@@ -330,12 +268,12 @@ class Board {
     } else if (piece.is(KING)) {
       [[1, 1], [1, -1], [-1, 1], [-1, -1], [0, 1], [0, -1], [1, 0], [-1, 0]]
         .forEach(delta => tryAddMove(x + delta[0], y + delta[1]));
-      if (piece.hasntMoved()) {
+      if (piece.hasNotMoved()) {
         const kingIndex = this.findIndex(piece);
         const [x, y] = this.getXandY(kingIndex);
 
         let leftRook = this.pieceAt(0, y);
-        if(leftRook.is(ROOK) && leftRook.hasntMoved()) {
+        if(leftRook.is(ROOK) && leftRook.hasNotMoved()) {
           // Check if spaces between rook and king are empty
           if(this.pieceAt(1, y).isEmpty() &&
             this.pieceAt(2, y).isEmpty() &&
@@ -351,7 +289,7 @@ class Board {
         }
 
         let rightRook = this.pieceAt(7, y);
-        if(rightRook.is(ROOK) && rightRook.hasntMoved()) {
+        if(rightRook.is(ROOK) && rightRook.hasNotMoved()) {
           // Check if spaces between rook and king are empty
           if(this.pieceAt(5, y).isEmpty() &&
             this.pieceAt(6, y).isEmpty()) {
diff --git a/src/backend.test.js b/src/backend.test.js
index d88f185..21a0d68 100644
--- a/src/backend.test.js
+++ b/src/backend.test.js
@@ -48,7 +48,7 @@ it('is created correctly', () => {
   ];
   expect(board.textFromState()).toBe(rows.join(''));
   for (const square of board.state.squares) {
-    expect(square.hasntMoved()).toBe(true);
+    expect(square.hasNotMoved()).toBe(true);
   }
 });
 
diff --git a/src/board.test.js b/src/board.test.js
index ff1bff2..dbb9883 100644
--- a/src/board.test.js
+++ b/src/board.test.js
@@ -52,7 +52,7 @@ it('is created correctly', () => {
   ];
   expect(board.textFromState()).toBe(rows.join(''));
   for (const square of board.state.squares) {
-    expect(square.hasntMoved()).toBe(true);
+    expect(square.hasNotMoved()).toBe(true);
   }
 });
 
diff --git a/src/components/Board.js b/src/components/Board.js
index 0108a6f..0b13a19 100644
--- a/src/components/Board.js
+++ b/src/components/Board.js
@@ -2,6 +2,7 @@ import React from 'react';
 import Popup from './Popup';
 
 import '../index.css';
+import { Piece } from '../logic';
 
 
 const BLACK = 0;
@@ -75,71 +76,6 @@ const Square = ({ bgColor, onClick, piece, className = "" }) => {
   );
 }
 
-class Piece {
-  constructor(color, type) {
-    this.color = color;
-    this.type = type;
-    this.passantable = false;
-    this.moves = 0;
-  }
-
-  setType(type) {
-    this.type = type;
-  }
-
-  getInfoText() {
-    if(this.moves === 1) {
-      return "Has made 1 move"
-    } else {
-      return "Has made " + this.moves + " moves"
-    }
-  }
-
-  isEmpty() {
-    return this.type === EMPTY;
-  }
-
-  isFull() {
-    return !this.isEmpty();
-  }
-
-  isBlack() {
-    return this.color === BLACK;
-  }
-
-  isWhite() {
-    return this.color === WHITE;
-  }
-
-  isEnemyOf(piece) {
-    if (this.color === EMPTY || piece.color === EMPTY) {
-      return false;
-    } else {
-      return this.color !== piece.color;
-    }
-  }
-
-  isFriendOf(piece) {
-    if (this.color === EMPTY || piece.color === EMPTY) {
-      return false;
-    } else {
-      return this.color === piece.color;
-    }
-  }
-
-  is(type) {
-    return this.type === type;
-  }
-
-  hasMoved() {
-    return this.moves !== 0;
-  }
-
-  hasntMoved() {
-    return !this.hasMoved();
-  }
-}
-
 class Board extends React.Component {
   constructor(props) {
     super(props);
@@ -380,12 +316,12 @@ class Board extends React.Component {
     } else if (piece.is(KING)) {
       [[1, 1], [1, -1], [-1, 1], [-1, -1], [0, 1], [0, -1], [1, 0], [-1, 0]]
         .forEach(delta => tryAddMove(x + delta[0], y + delta[1]));
-      if (piece.hasntMoved()) {
+      if (piece.hasNotMoved()) {
         const kingIndex = this.findIndex(piece);
         const [x, y] = this.getXandY(kingIndex);
 
         let leftRook = this.pieceAt(0, y);
-        if(leftRook.is(ROOK) && leftRook.hasntMoved()) {
+        if(leftRook.is(ROOK) && leftRook.hasNotMoved()) {
           // Check if spaces between rook and king are empty
           if(this.pieceAt(1, y).isEmpty() &&
             this.pieceAt(2, y).isEmpty() &&
@@ -401,7 +337,7 @@ class Board extends React.Component {
         }
 
         let rightRook = this.pieceAt(7, y);
-        if(rightRook.is(ROOK) && rightRook.hasntMoved()) {
+        if(rightRook.is(ROOK) && rightRook.hasNotMoved()) {
           // Check if spaces between rook and king are empty
           if(this.pieceAt(5, y).isEmpty() &&
             this.pieceAt(6, y).isEmpty()) {
diff --git a/src/logic.js b/src/logic.js
new file mode 100644
index 0000000..7721b04
--- /dev/null
+++ b/src/logic.js
@@ -0,0 +1,66 @@
+class Piece {
+  constructor(color, type) {
+    this.color = color;
+    this.type = type;
+    this.passantable = false;
+    this.moves = 0;
+  }
+
+  setType(type) {
+    this.type = type;
+  }
+
+  getInfoText() {
+    if(this.moves === 1) {
+      return "Has made 1 move"
+    } else {
+      return "Has made " + this.moves + " moves"
+    }
+  }
+
+  isEmpty() {
+    return this.type === EMPTY;
+  }
+
+  isFull() {
+    return !this.isEmpty();
+  }
+
+  isBlack() {
+    return this.color === BLACK;
+  }
+
+  isWhite() {
+    return this.color === WHITE;
+  }
+
+  isEnemyOf(piece) {
+    if (this.color === EMPTY || piece.color === EMPTY) {
+      return false;
+    } else {
+      return this.color !== piece.color;
+    }
+  }
+
+  isFriendOf(piece) {
+    if (this.color === EMPTY || piece.color === EMPTY) {
+      return false;
+    } else {
+      return this.color === piece.color;
+    }
+  }
+
+  is(type) {
+    return this.type === type;
+  }
+
+  hasMoved() {
+    return this.moves !== 0;
+  }
+
+  hasNotMoved() {
+    return !this.hasMoved();
+  }
+}
+
+export { Piece }
\ No newline at end of file