A collection of Ethereum based dApps

OLI dAppa Portal

The interest in blockchain and distributed ledger technology (DLT) has accelerated significantly since the emergence of Bitcoin back in 2008.

Though blockchain is still a very young technology and undergoing continuous development, its use is gaining momentum in various industry sectors including finance, real estate, healthcare, identity management, and the energy sector. Technologies built on top of blockchain are known as Decentralized Applications (dApps). dApps are web applications that have a frontend and a backend just like common web applications. However, their backend is running on a decentralized peer-to-peer network. One of the most popular blockchain networks to develop dApps…


A tutorial to dynamically build nested list from JSON data and vertical tree view with CSS3 only

Building a tree view for the hierarchical data is a common task in the front-end development of web applications. In most cases, hierarchical data is available in JavaScript Object Notation (JSON) which is a lightweight data format, and we need to represent this data as a tree on the webpage. In this tutorial, we will walk through the steps to dynamically create a nested list from the JSON data and style it to a vertically oriented tree view. …


Learn LaTeX from basic to advance level

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This is part 2 of the article series on getting started with LaTeX and explains how to create tables and lists in LaTex.

Part 1 of this article series covers basic software installation and how to compose a simple document in LaTeX.

Create Tables

In LaTeX, we can use table, tabular, or a combination of both environments to create tables. The tableenvironment provides additional functionality such as positioning, caption, label, and reference for the table. Whereas, the actual contents go inside the tabular environment.

We will start creating the very simplest table and then gradually develop it according to our choice. A…

Bootstrapping the dApp Development Experience

A step-by-step tutorial to building the back-end for Apps

Blockchain is a relatively young technology that is under continuous development. Similarly, applications built on the top of the blockchain are also still growing. As a result, there are several tools and best practices to streamline the development process. This tutorial will guide you through the steps to build a node.js back-end for a Decentralized Application (dApp). The tutorial introduces different developer tools and best practices and demonstrates how can we use them to boost the development experience.

The Big Picture

A Decentralized Application (dApp) is a kind of web application whose back-end runs on a decentralized network such as Blockchain. The dApp…


A tutorial for inter-snap communication using the content interface


While building applications in Python, we have to deal with dependency management that is not easy especially when it comes to package and ship your app. A snap bundles an application and all its dependencies to work across a range of Linux distributions. Snaps can be found and installed from the snap store.

In this tutorial, We will create two snaps to persist the user config data and then share this data with a consumer snap. The applications are developed in Python, the source code can be found here.

  • writer snap that will persist user config data to $SNAP_DATA
  • reader…


Learn LaTeX from basic to advance level

Image source:

LaTeX is a high-quality document preparation system that is used to produce professional-looking technical and scientific documents. To prepare a document in LaTeX, we need a LaTeX source file that contains LaTex code and actual contents of the document. This file ends with an extension .tex. The other thing we need is a text editor to edit the source file. Running the LaTeX compiler will compile the source file into a document interchange format such as pdf that can be then previewed in any pdf viewer.

This article series is aimed to help you get started with the LaTex from…


Unit-Testing of Smart Contracts with Truffle, Ganache, Mocha, and Chai


It is very common to write and compile Solidity code manually which is fine for small projects. However, as our project is growing bigger and bigger, it is good to have an automatic way of smart contracts development. In addition, testing Solidity code is crucial to avoid any problematic situation caused by a bug in the smart contract. There are different frameworks available for taking care of the development process. Truffle is one of them and is often regarded as the Ethereum Swiss Knife framework as it is a development environment, testing framework and asset pipeline for Ethereum.


This tutorial…

Muhammad Yahya

Ethereum Blockchain Developer @ OLI Systems

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