DEV Community: Gucci.koin 🔮

Getting Started with Koinos Blockchain: A Simple Hello World Application

Gucci.koin 🔮 — Mon, 17 Mar 2025 17:51:35 +0000

Getting Started with Koinos Blockchain: A Simple Hello World Application

Introduction

Blockchain technology continues to evolve beyond the limitations of first and second-generation chains. Koinos stands out as a next-generation blockchain designed with fee-less transactions, upgradability, and developer accessibility in mind. But how do newcomers begin exploring this powerful ecosystem?

Today, we'll explore a minimalist "Hello World" application that allows anyone to interact with the Koinos blockchain in seconds - no complex setup required.

What is the Koinos Hello World App?

At its core, our Hello World application is brilliantly simple - it's a single HTML file that connects directly to the Koinos blockchain and retrieves basic network information. No dependencies, no complicated build process, no installation.

The entire application consists of less than 100 lines of code, yet it successfully:

Connects to public Koinos RPC nodes
Implements automatic fallback between multiple endpoints
Retrieves current blockchain state information
Displays real-time data from the blockchain

How to Use It

Getting started with the Koinos Hello World app couldn't be simpler:

Visit the application at: https://isaacdozier.github.io/hello-koinos-world/
Click the "Get Blockchain Info" button
View real-time data directly from the Koinos blockchain

That's it! No account creation, no wallet setup, no transaction fees.

For developers who want to run it locally or customize it:

# Clone the repository
git clone https://github.com/isaacdozier/koinos-hello-world.git

# Open in your browser
# Simply open the index.html file in any web browser

Why This Simple App is Powerful

While our Hello World app may appear basic at first glance, its simplicity is precisely what makes it powerful for several reasons:

1. Zero Barrier to Entry

Traditional blockchain interactions often require:

Installing specialized software
Creating wallets
Acquiring tokens
Understanding complex interfaces

Our Hello World app eliminates all these barriers, allowing anyone to interact with the blockchain instantly.

2. Educational Value

For developers new to blockchain, this application provides:

A clear example of how to make JSON-RPC calls to a blockchain
Insight into blockchain data structures
A foundation to build upon with minimal complexity
Real-time feedback on blockchain state

3. Reliability Through Redundancy

Despite its simplicity, the application implements a sophisticated endpoint fallback system:

// Koinos RPC endpoints
const endpoints = [
    'https://api.koinos.io',
    'https://api.koinosblocks.com'
];

The app automatically tries multiple public nodes until it finds a responsive one, ensuring reliability even if some nodes are down.

4. Foundation for Further Development

This Hello World application can serve as the foundation for more complex applications:

Add wallet integration to enable transactions
Implement token viewing functionality
Create interfaces for smart contract interaction
Build monitoring tools for network health

Conclusion

The power of our Koinos Hello World application lies not in its complexity, but in its accessibility. By stripping blockchain interaction down to its simplest form, we've created a starting point that anyone can use.

Whether you're a curious newcomer, a developer exploring new platforms, or an educator teaching blockchain concepts, this simple application provides an immediate, hands-on way to interact with the Koinos blockchain.

Clone the repository, make your own modifications, and start exploring the possibilities of fee-less, upgradable blockchain technology today!

Ready to take the next step? Check out the Koinos documentation or join the Telegram to learn more.

Koinos, Smart Contracts, WASM & Protobuf

Gucci.koin 🔮 — Mon, 08 Apr 2024 05:02:31 +0000

Koinos Network utilizes 2 important features for working with Smart Contracts. WASM and Protobuf.

I wont try explaining how these work, others have already done a much better job. This post is meant to guide you in the right direction for working with Smart Contracts on Koinos Network and provide resources.

Here’s a few links to get started.

WASM :

https://medium.com/javascript-scene/what-is-webassembly-the-dawn-of-a-new-era-61256ec5a8f6

WebAssembly

Protobuf:

https://thecodebarbarian.com/working-with-protobufs-in-node-js.html

Protocol Buffers

These are great resources for understanding WASM and Protobuf, but how do these apply to Koinos? Here are a few links describing the uses of these features within the Network.

WASM: https://docs.koinos.io/architecture/smart-contracts/?h=wasm

Protobuf: https://docs.koinos.io/architecture/contract-abi/?h=protobuf

Checkout my Learn Koinos Github repo.

Connect to Koinos Blockchain in 10 Minutes

Gucci.koin 🔮 — Thu, 28 Mar 2024 08:58:11 +0000

Koinos is made to be accessible to developers and users. With just a few lines of code, we can interact with the blockchain.

This tutorial has been expanded at Learn Koinos Github repo.

Koinos Community Telegram

Koinos Wiki

Getting Started

Learn to Use Terminal

Install Node.js

Clone this repo

git clone https://github.com/isaacdozier/learn-koinos.git
cd learn-koinos

How to Clone a Repository

Install Dependencies

npm install @koindx/v2-sdk

The Basics of Dependencies for Node.js & NPM

Koindx V2-SDK Examples

Run Examples

Example_4.js : returns Koin & USDT Pool Reserves

const { ChainId, Fetcher, KOIN, Token, Percent} = require("@koindx/v2-sdk");
const BigNumber = require('bignumber.js');

async function go(){
    try{
        // DECLARE ASSETS
        // KOIN can be declared directly with Koindx sdk
        const koin = new KOIN(ChainId.MAINNET);

        // USDT is NOT a native asset and is declared using the Token class
        // This same operation would be used for other alt-token in the ecosystem
        const usdt_contract_address = '19WrWze3XAoMa3Mwqys4rJMP6emZX2wfpH'
        const usdt = new Token(ChainId.MAINNET, usdt_contract_address);

        // This retrieves the Koin/USDT pool info by utilizing the Koindx SDK
        const PAIR = await Fetcher.fetchPairData(ChainId.MAINNET, koin, usdt);

        // Lets declare our availbile reserves to get an estimated ratio
        // This can be used to get an estimated exchange rate for any given pool
        // We are using Percent to parse a BigNumber.js object
        const koin_reserves = new Percent(PAIR.reserve_0)
        const usdt_reserves = new Percent(PAIR.reserve_1)

        console.log('Koin Reserves: ', koin_reserves.numerator)
        console.log('USDT Reserves: ', usdt_reserves.numerator / usdt_reserves.denominator)

    } catch (error) {
        console.error(error);
    }
}

go()

Terminal

node example_4.js

Output

Koin Reserves:  BigNumber { s: 1, e: 12, c: [ 8752538877288 ] }
USDT Reserves:  877155023.1824

BigNumber.js is an arithmitic standard used for working with a wide range of numbers, strings and object types representing a numeric value.

"The library exports a single constructor function, BigNumber, which accepts a value of type Number, String or BigNumber"

We are only reading these values as they are returned to us, but if you want to create them in your app you need to include the dependency below.

const BigNumber = require('bignumber.js');

This makes working with numbers easier for developers.

Learn how to work with BigNumber.js

Arithmic functions with numbers and strings

console.log(koin_reserves * 1)

Output: 8810421275766

console.log(koin_reserves * '1')

Output: 8810421275766

Simplify operations with Percent

const koin_reserves = new Percent(PAIR.reserve_0)

console.log('Koin Reserves: ', koin_reserves.numerator / koin_reserves.denominator)

Koin Reserves:  875956851.2107
USDT Reserves:  Percent {
  numerator: BigNumber { s: 1, e: 12, c: [ 8764493211385 ] },
  denominator: BigNumber { s: 1, e: 4, c: [ 10000 ] }
}

Let’s Build a Dapp with Node.js and Koinos Pro [PART 2] Create a Wallet

Gucci.koin 🔮 — Wed, 27 Mar 2024 00:36:02 +0000

In part 1 we created a Koinos Pro account and generated our API key. We also need a wallet to manage our assets on the blockchain.

There are a few wallets to choose from, but for this we will use Kondor (Browser Extension).

Find more wallet options at: https://koinos.wiki/Applications#Wallets

https://chromewebstore.google.com/detail/kondor/

Go ahead and download the Konder Wallet, and be sure to keep your Seed Phrase secure. Anyone with this has access to your wallet!

After you’ve set up your wallet, we need to get some tKoin to use on Testnet. This is a free resource we can get airdropped from Koinos Discord.

To do this, we’ll copy our public address located here:

We don’t need to worry about switching the wallet to Testnet because it will be determined by the API endpoint we choose at https://koinos.pro/. We are only using Kondor to create a wallet.

Now we need to go to discord faucet channel and request tKoin. Copy the command below and follow the link provided.

!faucet [your public key here]

Go here: https://discord.com/channels/613823471679438898/860644240954359829

Paste the command with your public address

You should see similar results to below.

To ensure funds were deposited, you can switch to Testnet for verification in Kondor Wallet.

Now you’re ready to start making transactions!

If you are having any difficulties, feel free to ask for help at..

Koinos Telegram Main Channel: https://t.me/koinos_community

Koinos Discord General Chat: https://discord.com/channels/613823471679438898/613823471679438900

In part 3 I will break down the basic elements of Koilib and how to prepare a transaction with Node.js. For now, I’ll leave you with a brief description and link to do your own research.

Koilib

Koilib is fundamental when interacting with the Koinos Network and we will be following the example code at https://joticajulian.github.io/koilib/ in part 3.

First time using Koinos? Go swap your tKoin at KoinDX Testnet app and experience a free-to-use experience!

https://testnet.koindx.com/swap

Let’s Build a Dapp with Node.js and Koinos Pro [PART 1] Generate API Key

Gucci.koin 🔮 — Tue, 26 Mar 2024 16:03:14 +0000

This is part 1 of the ‘Let’s Build on Koinos’ series where I go step-by-step on how to build a Node.js application capable of interacting with the Koinos blockchain.

For the sake of clarity, in this series, “Dapp” will refer to any application that utilizes blockchain technology. We will be creating a Dapp that can call smart contract functions created and audited by other developers.

You do NOT need to code smart contracts to harness the power of blockchain technology. Making use of existing contracts is a great way to start.

Let’s get started.

Step 1: Generate API Key via Koinos Pro

This can be done quickly with an API endpoint provided by Koinos Pro to make GET and POST json requests.

Free version available at https://koinos.pro/

Fast account creation (5 mins)

After creating an account, generate an API key.

We can choose between MAINNET and TESTNET, let’s use testnet for this tutorial.


https://api.harbinger.koinos.pro/jsonrpc?apikey=[your API key here]

Replace [your API key here] with… you guessed it, your API key!

API Documentation: https://docs.koinos.pro/api_keys/

Nothing we need here, but it’s a useful link with a list of API connection methods.

DEV Community: Gucci.koin 🔮

Getting Started with Koinos Blockchain: A Simple Hello World Application

Getting Started with Koinos Blockchain: A Simple Hello World Application

Introduction

What is the Koinos Hello World App?

How to Use It

Why This Simple App is Powerful

1. Zero Barrier to Entry

2. Educational Value

3. Reliability Through Redundancy

4. Foundation for Further Development

Conclusion

Koinos, Smart Contracts, WASM & Protobuf

These are great resources for understanding WASM and Protobuf, but how do these apply to Koinos? Here are a few links describing the uses of these features within the Network.

Connect to Koinos Blockchain in 10 Minutes

Getting Started

Clone this repo

Install Dependencies

Run Examples

Terminal

Output

Arithmic functions with numbers and strings

Simplify operations with Percent

Let’s Build a Dapp with Node.js and Koinos Pro [PART 2] Create a Wallet

We don’t need to worry about switching the wallet to Testnet because it will be determined by the API endpoint we choose at https://koinos.pro/. We are only using Kondor to create a wallet.

You should see similar results to below.

Now you’re ready to start making transactions!

In part 3 I will break down the basic elements of Koilib and how to prepare a transaction with Node.js. For now, I’ll leave you with a brief description and link to do your own research.

Koilib

Let’s Build a Dapp with Node.js and Koinos Pro [PART 1] Generate API Key

Step 1: Generate API Key via Koinos Pro

After creating an account, generate an API key.

We can choose between MAINNET and TESTNET, let’s use testnet for this tutorial.

In Part 2 we will create a wallet and get tKoin airdropped for interacting with the blockchain.