This is an official tutorial published earlier on Ontology Medium blog
Excited to publish it for Habr readers. Feel free to ask any related questions and suggest a better format for tutorial materials

Foreword

• Part 1: Blockchain & Block API
• Part 2: Storage API
• Part 3: Runtime API
• Part 4: Native API
• Part 5: Upgrade API
• Part 6: Execution Engine API
• Part 7: Static & Dynamic Call API

1. How to Use Blockchain API

How does Bootstrap work?

This article aims to show how to use Kotlin Coroutines and remove Reaxtive eXtensions (Rx).

Benefits

To start let's consider four benefits of Coroutines over Rx:

Suspending over Blocking

To run non-blocking code using Rx you'd write something like this:

Observable.interval(1, TimeUnit.SECONDS)
    .subscribe {
        textView.text = "$it seconds have passed"
    }

Which is effectively creating a new thread. Threads are heavy objects in terms of memory and performance.

Both are critical in the mobile development world.

You can achieve the same behavior using the following snippet:

launch {
    var i = 0
    while (true){
        textView.text = "${it++} seconds have passed"
        delay(1000)
    }
}

Essentially, Coroutines are light-weight threads but we don't create any real thread.
Here we are using non-blocking delay() function, which is a special suspending function that does not block a thread but suspends the Coroutine.

I am a full-stack developer at Syncrasy Tech (IT solutions company). I love writing React codes. But why I am telling you this as we are here to discuss the Vue.js best practices for web development. I am telling you this so that you can understand my background and why I’m discussing here the Vue.js.

I love working on React codes, but I hate reading them. This is the reason where I fail to code. Even with the best code review practices, I can’t figure out the nesting of React components that simply helps to create more complex UI structures in web apps.

The solution to this problem is Vue that is now not so new in the block of web app development. I have heard a lot about Vue async components, server-side rendering, tools, and libraries. Perhaps you find this myriad of terms to be confusing. Believe me, you’re not alone in that, many developers of all levels feel the same way when they don’t know the Vue best practices.

A few days later, I finally decided to get my codes into it. What I am sharing here are the numerous best practices that I have learned through my experience with Vue. I’m ready to share what I’d find.

As per the latest stats reveal, there are more than 2.7 billion smartphone users globally and over 2.8 million apps on Google Play Store.

Now, it's a fact that the number of mobile users is increasing at outstanding speed, and so is the name of apps on Google Play Store.

But does all the apps success to make a difference? No, but just a handful of having stood out and gain popularity.

For instance, there are several games on the Play Store, but why only Candy Crush, Subway Surfers and Angry Birds topped the charts while the other games struggle for even ten downloads.

The trick is to provide the players with what they want, and in turn, the response for such apps is tremendous.

However, at this point, when the competition is very high, it's challenging to come up with something new that can stand out from the crowd.

It's crucial to create a brand name so that people can talk about it.

What is Swoft?

Swoft is a PHP microservices coroutine framework based on the Swoole extension. Like Go, Swoft has a built-in coroutine web server and a common coroutine client and is resident in memory, independent of traditional PHP-FPM. There are similar Go language operations, similar to the Spring Cloud framework flexible annotations, powerful global dependency injection container, comprehensive service governance, flexible and powerful AOP, standard PSR specification implementation and so on.

Through three years of accumulation and direction exploration, Swoft has made Swoft the Spring Cloud in the PHP world, which is the best choice for PHP's high-performance framework and microservices management.

Elegant service governance

Swoft officially recommends that developers use service mesh patterns, such as the Istio/Envoy framework, to separate business and service governance, but Swoft also provides a set of microservices components for small and medium-sized businesses to quickly build microservices.

JavaScript has been ruling the tech arena for more than two decades and helping developers simplifying complex tasks. It allows developers to implement complex task web pages in a most simplified manner. For most of the developers minified JavaScript file is the common phenomena while very few developers may be aware of Optimized JavaScript code. While meeting through many Javascript developers, I have come to know that Optimized JavaScript code is something that confuses developers, some of them might be doing it, but they are not aware of this.

What is an Optimized JavaScript Code

When combinations of uniquely programmed logics along with small hacks utilized to enhance performance and speed is known as Optimized JavaScript code. Optimization not only optimizes performance and speed but also saves maximum development time. When you save time, you save some bucks as well.

So, I am here with some useful and fruitful hacks to help developers optimize performance, enhance speed and save time. Hope, you like the article and after going through it, you may utilize the best of Optimized JavaScript code.

What is 3D printing?

Abstract

This week I spent coding my very first public pet-app based on Telegram chat bot which acts as a Bitcoin wallet and allows to send and receive tips between Telegram users and other so-called “Lightning Apps”. I assume that you are familiar with Bitcoin & Telegram in general, i’ll try to post short and without deep jump into details. More resources about Bitcoin can be found here and Telegram is simply an instant messenger that allows you to create your custom apps (chat-bots) using their platform.

What are the key points of such app?

• Allows to rate other users ideas and answers with real value instead of
  ‘virtual likes’. This brings online conversation to completely new level
• Real example of working micro-payment app which can act with other entities
  over internet using open protocol
• All the modules are open-source projects and can be easy re-used and adjusted
  for your own project. App does not relay on third-party commercial services.
  Even it falls under e-commerce field, which is currently almost closed, the app
  is based on open solutions.

What are the use-cases?

something like this…

This post describes the steps needed for setting up automatic SSL certificates creation and renewal, using Let's Encrypt as the automated Certificate Authority, which provides a well-maintained API.
acme-dns-route53 is the tool to obtain SSL certificates from Let’s Encrypt using DNS-01 challenge with Route53 and Amazon Certificate Manager by AWS. acme-dns-route53 also has the built-in functionality for using this tool inside AWS Lambda, and this is what we are going to do.

Intro

.NET is a relative newcomer in the open-source world, and its popularity is nowhere near mainstream platforms like Node.js. So you can imagine there're few tutorials that deal with .NET and frameworks such as ASP.NET on Heroku. And those that do, probably won't use containers.

Do you see C#/.NET here? Yes, me neither.