diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c2658d7
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+node_modules/
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..505372b
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# Blockchain implemented by JavaScript
+
+Inspired by [learn-blockchains-by-building-one](https://hackernoon.com/learn-blockchains-by-building-one-117428612f46)
\ No newline at end of file
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diff --git a/package.json b/package.json
new file mode 100644
index 0000000..00e8428
--- /dev/null
+++ b/package.json
@@ -0,0 +1,23 @@
+{
+  "name": "blockchain-ts",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "start": "ts-node src/main.ts"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "body-parser": "^1.19.0",
+    "crypto-js": "^4.0.0",
+    "express": "^4.17.1",
+    "uuid": "^8.2.0"
+  },
+  "devDependencies": {
+    "@types/node": "^14.0.23",
+    "ts-node": "^8.10.2",
+    "typescript": "^3.9.6"
+  }
+}
diff --git a/src/Blockchain.ts b/src/Blockchain.ts
new file mode 100644
index 0000000..289ca41
--- /dev/null
+++ b/src/Blockchain.ts
@@ -0,0 +1,127 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:06:38
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-17 18:58:16
+* @E-mail: justbefree@126.com
+*/
+import { default as HttpAsync } from "./http";
+import { Transactions } from "../types/transactions";
+import { Block } from "../types/block";
+import { Node } from "../types/node";
+import { Callback } from "../types/callback";
+import sha256 from "crypto-js/sha256";
+const http = new HttpAsync();
+class Blockchain {
+
+  private currentTransactions: Array<Transactions>;
+  private chain: Array<Block>;
+  private nodes: Array<Node>;
+  
+  constructor() {
+    this.chain = [];
+    this.currentTransactions = [];
+    this.nodes = [];
+    this.newBlock(0, "100");
+  }
+
+  public getChain(): Array<Block> {
+    return this.chain;
+  }
+  public getChainLength(): number {
+    return this.chain.length;
+  }
+
+  public isNodeExists(node: Node): boolean {
+    return this.nodes.indexOf(node) > -1;
+  }
+
+  public registerNodes(node: Node): void {
+    if (!this.isNodeExists(node)) {
+      this.nodes.push(node);
+    }
+  }
+
+  public getNodes(): Array<Node> {
+    return this.nodes;
+  }
+
+  public newBlock(proof: number, previousHash: string): Block {
+    const chainLength: number = this.chain.length;
+    const block: Block = {
+        index: chainLength + 1,
+        timestamp: Date.now(),
+        transactions: this.currentTransactions,
+        proof: proof,
+        previousHash: previousHash || Blockchain.hash(this.chain[chainLength - 1])
+    };
+    this.currentTransactions = [];
+    this.chain.push(block);
+    return block;
+  }
+  static hash(block: Block): string {
+    const blockString: string = JSON.stringify(block);
+    return sha256(blockString).toString();
+  }
+  static validProof(lastProof: number, proof: number, lastHash: string): boolean {
+    const guess: string = `${lastProof}${proof}${lastHash}`;
+    const guessHash: string = sha256(guess).toString();
+    // console.log("guessHash----------", guessHash);
+    return guessHash.substr(-4) === "0000";
+  }
+  public proofOfWork(lastBlock): number {
+    const lastProof: number = lastBlock["proof"];
+    const lastHash: string = Blockchain.hash(lastBlock);
+    let proof = 1;
+    while(!Blockchain.validProof(lastProof, proof, lastHash)) {
+      proof += 1;
+    }
+    return proof;
+  }
+  public newTransaction(transaction: Transactions): number {
+    this.currentTransactions.push(transaction);
+    const block: Block = this.lastBlock();
+    return block["index"] + 1;
+  }
+  public lastBlock(): Block {
+    return this.chain[this.chain.length - 1];
+  }
+  public validChain(chain: Array<Block>): boolean {
+    let lastBlock: Block = chain[0];
+    let currentIndex: number = 1;
+    while (currentIndex < chain.length) {
+      let block: Block = chain[currentIndex];
+      let lastBlockHash: string = Blockchain.hash(lastBlock);
+      if (lastBlockHash !== block["previousHash"] || !Blockchain.validProof(lastBlock["proof"], block["proof"], lastBlockHash)) {
+        return false;
+      }
+      lastBlock = block;
+      currentIndex += 1;
+    }
+    return true;
+  }
+
+  private getLongestChain(callback: Callback | null): void {
+    const neighbours: Array<Node> = this.nodes;
+    let maxLength: number = this.chain.length;
+    let newChain: Array<Block> = this.chain;
+    let isNewChain: boolean = false;
+    Promise.all(neighbours.map(node => http.get(`${node}/chain`))).then(res => {
+      res.forEach(chainObjcet => {
+        if (chainObjcet.length > maxLength && this.validChain(chainObjcet.chain)) {
+          maxLength = chainObjcet.length;
+          newChain = chainObjcet.chain;
+          isNewChain = true;
+        }
+      });
+      callback({ chain: newChain, isNewChain });
+    }).catch(err => {
+      callback({ chain: newChain, isNewChain, exceptions: err });
+    });
+  }
+
+  public resolveConflicts(callback: Callback | null): void {
+    this.getLongestChain(callback);
+  }
+};
+export default Blockchain;
diff --git a/src/http.ts b/src/http.ts
new file mode 100644
index 0000000..5508293
--- /dev/null
+++ b/src/http.ts
@@ -0,0 +1,39 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 16:34:18
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-17 19:07:20
+* @E-mail: justbefree@126.com
+*/
+import * as http from "http";
+
+class HttpAsync {
+  constructor() {}
+  public async get(url: string): Promise<any> {
+    const promise = new Promise<any>((resolve, reject) => {
+      http.get(url, res => {
+        const { statusCode } = res;
+        if (statusCode !== 200) {
+          res.resume();
+          reject("Request failed");
+        } else {
+          res.setEncoding("utf8");
+          let rowData: string = "";
+          res.on("data", (chunk) => { rowData += chunk; });
+          res.on("end", () => {
+            try {
+              const parsedData = JSON.parse(rowData);
+              resolve(parsedData);
+            } catch (e) {
+              console.error(e);
+              reject(e);
+            }
+          });
+        }
+      });
+    });
+    return promise;
+  }
+};
+
+export default HttpAsync;
diff --git a/src/main.ts b/src/main.ts
new file mode 100644
index 0000000..9b7983b
--- /dev/null
+++ b/src/main.ts
@@ -0,0 +1,98 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:00:35
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-17 18:58:58
+* @E-mail: justbefree@126.com
+*/
+const bodyParser = require("body-parser");
+import { Block } from "../types/block";
+import { Transactions } from "../types/transactions";
+import { Node } from "../types/node";
+import { default as Blockchain } from "./Blockchain";
+import { default as express } from "express";
+import { v4 as uuidv4 } from 'uuid';
+const app = express();
+const blockchain = new Blockchain();
+app.get("/mine", (req, res) => {
+  // 挖矿
+  const lastBlock: Block = blockchain.lastBlock();
+  const proof: number = blockchain.proofOfWork(lastBlock);
+  const transaction: Transactions = { amount: 5, recipient: uuidv4(), sender: "000" };
+  blockchain.newTransaction(transaction);
+  const previousHash: string = Blockchain.hash(lastBlock);
+  const block: Block = blockchain.newBlock(proof, previousHash);
+  const response = {
+      message: "New Block Forged",
+      index: block["index"],
+      transactions: block["transactions"],
+      proof: block["proof"],
+      previousHash: block["previousHash"]
+  };
+  res.send(response);
+});
+
+app.get("/chain", (req, res) => {
+  req.accepts('application/json');
+  const response = {
+    chain: blockchain.getChain(),
+    length: blockchain.getChainLength()
+  };
+  res.send(response);
+});
+
+app.post("/transactions/new", bodyParser.json(), (req, res) => {
+  const required = ["sender", "recipient", "amount"];
+  const transaction: Transactions = req.body;
+  let pass: boolean = true;
+  let message: string;
+  required.forEach(param => {
+    if (!(param in transaction)) {
+      pass = false;
+      message = `${param} is required`;
+    }
+  });
+  if (pass) {
+    const index: number = blockchain.newTransaction(transaction);
+    message = `Transaction will be added to Block ${index}`;
+    res.send({ message });
+  } else {
+    res.send({ message });
+  }
+});
+
+app.post("/nodes/register", bodyParser.json(), (req, res) => {
+  const nodes: Array<Node> = req.body.nodes;
+  let message: string;
+  if (!nodes) {
+    message = "nodes is required";
+  }
+  if (!nodes.length) {
+    message = "nodes type must be an Array";
+  }
+
+  nodes.forEach(node => {
+    if (blockchain.isNodeExists(node)) {
+      message = `The Node ${node} is already exists`;
+    } else {
+      blockchain.registerNodes(node);
+      message = "New nodes have been added";
+    }
+  });
+  res.send({ message, totalNodes: blockchain.getNodes() });
+});
+
+
+app.get("/nodes/resolve", (req, res) => {
+  blockchain.resolveConflicts((chain) => {
+    if (chain.isNewChain) {
+      res.send({ message: "Our chain was replaced", chain });
+    } else {
+      res.send({ message: "Our chain is authoritative", chain });
+    }
+  });
+});
+
+app.listen(8000, () => {
+  console.log("Server is running at 8000");
+});
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..b8274e4
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "declaration": false,
+    "target": "es6",
+    "lib": ["es2015", "dom"],
+    "allowJs": true,
+    "resolveJsonModule": true,
+    "esModuleInterop": true,
+  },
+  "include": [
+    "src/**/*"
+   ],
+  "exclude": [
+    "node_modules"
+  ]
+}
\ No newline at end of file
diff --git a/types/block.ts b/types/block.ts
new file mode 100644
index 0000000..47f82d2
--- /dev/null
+++ b/types/block.ts
@@ -0,0 +1,16 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:14:44
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-16 18:09:01
+* @E-mail: justbefree@126.com
+*/
+
+import { Transactions } from "./transactions";
+export interface Block {
+  index: number;
+  previousHash: string;
+  proof: number;
+  timestamp: number;
+  transactions: Array<Transactions>;
+};
diff --git a/types/callback.ts b/types/callback.ts
new file mode 100644
index 0000000..c0b8286
--- /dev/null
+++ b/types/callback.ts
@@ -0,0 +1,9 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-17 17:52:21
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-17 17:53:37
+* @E-mail: justbefree@126.com
+*/
+
+export type Callback = (args: any) => any;
diff --git a/types/index.ts b/types/index.ts
new file mode 100644
index 0000000..7256b06
--- /dev/null
+++ b/types/index.ts
@@ -0,0 +1,8 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:13:00
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-16 14:13:07
+* @E-mail: justbefree@126.com
+*/
+
diff --git a/types/node.ts b/types/node.ts
new file mode 100644
index 0000000..513a321
--- /dev/null
+++ b/types/node.ts
@@ -0,0 +1,11 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:42:17
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-16 14:42:53
+* @E-mail: justbefree@126.com
+*/
+
+export interface Node {
+  [propName: string]: any;
+};
\ No newline at end of file
diff --git a/types/transactions.ts b/types/transactions.ts
new file mode 100644
index 0000000..f459997
--- /dev/null
+++ b/types/transactions.ts
@@ -0,0 +1,13 @@
+/*
+* @Author: Just be free
+* @Date:   2020-07-16 14:10:33
+* @Last Modified by:   Just be free
+* @Last Modified time: 2020-07-16 15:16:05
+* @E-mail: justbefree@126.com
+*/
+
+export interface Transactions {
+  amount: number;
+  recipient: string;
+  sender: string;
+};