CrowdFunding Assignment

.github/pull_request_template.md

@@ -1,9 +1,12 @@
 ## Summary
+
 What does this PR implement?
 
 ## Testing
+
 - [ ] Unit tests added
 - [ ] Tests passing locally
 
 ## Notes
-Any assumptions or trade-offs?
+
+Any assumptions or trade-offs?

.github/workflows/ci.yml

@@ -0,0 +1,24 @@
+name: CI
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  formatting:
+    name: Code Formatting (Prettier)
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - name: Run Prettier check
+        run: npx prettier --check .

.gitignore

@@ -4,6 +4,37 @@
 package-lock.json
 node_modules
 
+# Dependencies
+lib/
+
 # Rust build artifacts
 /target
 **/target
+
+# Hardhat / Foundry build artifacts
+artifacts/
+cache/
+typechain-types/
+out/
+build-info/
+
+# Solidity compiler binary
+soljson-latest.js
+
+# Hardhat Ignition build info (large generated files)
+ignition/deployments/**/build-info/
+
+# Logs
+*.log
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# IDE
+.idea/
+*.swp
+*.swo
+
+
+lib/

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "assignments/foundry-test-assignment/lib/openzeppelin-contracts"]
+	path = assignments/foundry-test-assignment/lib/openzeppelin-contracts
+	url = https://github.com/OpenZeppelin/openzeppelin-contracts

.prettierrc

@@ -4,4 +4,4 @@
   "trailingComma": "es5",
   "printWidth": 80,
   "tabWidth": 2
-}
+}

CONTRIBUTING.md

@@ -1,35 +1,40 @@
 # How to Contribute
 
 1. Getting Started
- - Fork the repository
- - Sync with upstream
- - Create a feature branch
+
+- Fork the repository
+- Sync with upstream
+- Create a feature branch
 
 2. Branch Naming Convention
-Example:
-`submission/assignment-01/<github-username>`
+   Example:
+   `submission/assignment-01/<github-username>`
 
 3. Commit Message Guidelines
 
 Example (Conventional Commits–lite):
+
 ```
 feat: implement token transfer logic
 fix: handle zero-address edge case
 test: add coverage for revert conditions
 ```
 
 4. Pull Request Checklist
+
 - [x] Code compiles
 - [x] Tests pass
 - [x] README included
 - [x] No changes outside /submissions
 
 5. PR Review Process
+
 - [x] Automated checks
 - [x] Manual review by mentors
 - [x] Required fixes before merge
 
 6. Common Mistakes to Avoid
+
 - Editing assignment specs
 - Submitting compiled artifacts
-- Force-pushing after review
+- Force-pushing after review

README.md

@@ -1,12 +1,15 @@
 # Cohort 8
+
 Blockchain Development Bootcamp — Cohort 8
 
 This repository contains official technical materials, specifications, assignments, and collaboration artifacts for the 8th edition of our blockchain program. Dev participants are expected to actively use this repository throughout the program for learning, development, version control, and peer collaboration.
 
 #### Repository Structure
+
 The repository will evolve over time, but a typical structure looks like:
+
 ```cohort-8/
-├── README.md                     # Repository overview and instructions             
+├── README.md                     # Repository overview and instructions
 ├── assignments/                  # Coding exercises and assessments
 ├── projects/
 │   ├── templates/                # Starter project templates
@@ -15,12 +18,14 @@ The repository will evolve over time, but a typical structure looks like:
 ```
 
 #### Setup
+
 Clone the repository:
+
 ```
 git clone https://github.com/BlockheaderWeb3-Community/cohort-8.git
 cd cohort-8
 ```
 
 #### Code Formatting
-This repository uses Prettier for formatting. Install the Prettier extension in your editor and enable Format on Save.
 
+This repository uses Prettier for formatting. Install the Prettier extension in your editor and enable Format on Save.

assignment05/README.md

@@ -0,0 +1 @@
+https://hackmd.io/@gXPhwY6gQKmHFQ55mXXm1g/S1b3oc_LWg

assignment05/package.json

@@ -0,0 +1,21 @@
+{
+  "dependencies": {
+    "bip32": "^5.0.0",
+    "bip39": "^3.1.0",
+    "ethereumjs-util": "^7.1.5",
+    "hdkey": "^2.1.0",
+    "keccak": "^3.0.4",
+    "secp256k1": "^5.0.1",
+    "tiny-secp256k1": "^2.2.4"
+  },
+  "name": "key-key",
+  "version": "1.0.0",
+  "main": "key.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "description": ""
+}

assignment05/walletad.js

@@ -0,0 +1,41 @@
+const bip39 = require("bip39");
+const { BIP32Factory } = require("bip32");
+const tinysecp = require("tiny-secp256k1");
+const bip32 = BIP32Factory(tinysecp);
+const secp256k1 = require("secp256k1");
+const { keccak256 } = require("ethereumjs-util");
+const crypto = require("crypto");
+
+const entropy = crypto.randomBytes(32);
+
+
+const mnemonic = bip39.entropyToMnemonic(entropy);
+console.log("Mnemonic Phrase:\n", mnemonic);
+
+const seed = bip39.mnemonicToSeedSync(mnemonic);
+
+const root = bip32.fromSeed(seed);
+
+const path = "m/44'/60'/0'/0/0";
+const child = root.derivePath(path);const ADDRESS_COUNT = 4;
+
+for (let i = 0; i < ADDRESS_COUNT; i++) {
+  const path = `m/44'/60'/0'/0/${i}`;
+  const child = root.derivePath(path);
+
+  const privateKey = child.privateKey;
+  // console.log("\nPrivate Key:\n", Buffer.from(privateKey).toString("hex"));
+
+  const publicKeyArray = secp256k1.publicKeyCreate(privateKey, false).slice(1);
+  const publicKey = Buffer.from(publicKeyArray);
+  // console.log("\nPublic Key (64 bytes):\n", publicKey.toString("hex"));
+
+  const hash = keccak256(publicKey);
+
+  const address = "0x" + hash.slice(-20).toString("hex");
+  // console.log("\nEthereum Address:\n", address);
+  console.log(`\nAddress #${i}`);
+  console.log("\nPrivate Key:\n", Buffer.from(privateKey).toString("hex"));
+  console.log("\nPublic Key (64 bytes):\n", publicKey.toString("hex"));
+  console.log("\nEthereum Address:\n", address);
+};

assignments/1/1-gas/README.md

@@ -10,6 +10,7 @@ This is a **conceptual example**, not an exact implementation of Ethereum’s ga
 ## What This Program Does
 
 The program:
+
 - Defines a unit of computational work
 - Defines a price per unit of work
 - Multiplies the two values to compute a gas fee
@@ -24,10 +25,10 @@ Gas Fee = Computational Work × Price Per Unit
 
 
 
-### Gas 
+### Gas
 Gas is a unit of measurement. It measures how much computation a transaction uses
 
-### Gas Limit 
+### Gas Limit
 Gas limit is the maximum amount of gas you are willing to use for a transaction.
 
 ### Gas price
@@ -40,3 +41,4 @@ A base fee is calculated automatically by the network
 It changes depending on network congestion
 This base fee is burned (destroyed forever)
 **Burned ETH is removed from circulation → makes ETH deflationary**
+```

assignments/1/1-merkle-root/README.md

@@ -3,6 +3,7 @@
 This project demonstrates how a **Merkle Tree** works by hashing a list of transactions and recursively combining them to produce a **Merkle root**.
 
 The implementation is written in Rust and shows:
+
 - How transactions are hashed
 - How Merkle tree levels are built
 - How the final Merkle root is computed
@@ -35,3 +36,4 @@ Pairwise hash concatenation
 Repeated hashing of levels
    ↓
 Merkle Root
+```

assignments/3-block-observation/README.md

@@ -1,8 +1,9 @@
 # Observations on a Block explorer(Etherscan) and a Transaction hash
 
-
 ### 1. Exploring the block explorer
+
 While on the block explorer, I observed some standard metrics which were:
+
 - Ether price: This gives the current market value of one `ether`
 - Market cap: Short for market capitalisation, it is calculated by multiplying the current value of ether by the total circulating supply.
 - Transactions: This shows the total number of transactions processed in ethereum over a period of time.
@@ -11,7 +12,9 @@ While on the block explorer, I observed some standard metrics which were:
 - Latest transaction: This shows all the recent transaction that were mined in a block.
 
 ### 2. Exploring a block on etherscan (Block explorer)
+
 After clicking on a recent block under the `Latest blocks` section, there were some details I observed which were:
+
 - Block Height: It shows the number in which the block is positioned, right from the genesis block. It shows the length of the blockchain.
 - Status: It shows if a block is fiinalised/confirmed
 - Timestamp: It shows the date and time at which the block was created.
@@ -21,17 +24,20 @@ After clicking on a recent block under the `Latest blocks` section, there were s
 - Block difficulty: This is the total difficulty of the chain up until the recent recent block.
 
 ### 3. Exploring a transaction hash
+
 <!-- While on my rabby wallet, I wanted to view my transaction history, so I clicked on the `Transactions` icon, and selected the option `Custom network`, there I saw the transactions I made then selected the particular one I wanted, after clicking I observed some details like: -->
+
 - **Sending ETH to my address**
-On my rabby wallet, I clicked on `Send` button which prompted me to input an amount and put in the receivers' address, since I'm sending to myself, I inputted my wallet address. After that I clicked `Send` then I signed and confirmed the transaction. Immediately I was redirected to `etherscan.io`, there I observed some details like:
+  On my rabby wallet, I clicked on `Send` button which prompted me to input an amount and put in the receivers' address, since I'm sending to myself, I inputted my wallet address. After that I clicked `Send` then I signed and confirmed the transaction. Immediately I was redirected to `etherscan.io`, there I observed some details like:
 - Transaction hash: It is unique identifier that is generated cryptographically when a transaction is created, it's more like a proof that a transaction a has gone through.
 - Status: This shows if a transaction was successful or not
 - Block: This shows the block height which this transaction is included.
 - Timestamp: The date a time in which this transaction was created.
-- From:  Senders' address
+- From: Senders' address
 - To: Receivers' address
 - Value: The value of ETH I'm spending
 
 ## Conclusion
+
 The ethereum block explorer is a powerful tool that shows in real time the processes and production of blocks and transactions.
-As well as a transaction hash that serves as a proof that an exchange of value has already taken place.
+As well as a transaction hash that serves as a proof that an exchange of value has already taken place.