Back-end

The de facto standard for web application security is the Open Web Application Security Project’s Top 10 Project. It lists the ten most prevalent security threats based on an extensive amount of data and community feedback and was updated in late 2017.

In this article, Toptal Freelance Full-stack and System Security Developer Hrvoje Gazibara discusses the changes to the OWASP Top 10’s most recent revision by illustrating new vulnerabilities, and even some that were removed.

Bulletproof data validation is fundamental to implementing a back-end API. Find out how datalize, a Node.js library, makes this easy—and formats your data nicely, too.

Without proper state management, your Angular app will become a UX nightmare. But even with that solved, persisting state across sessions and devices can be tricky. This tutorial shows how to leapfrog that challenge using Firebase.

As simple as your RESTful API may be, even internal users will want a JavaScript package that will do all the heavy lifting for them. Why build each CRUD request by hand, or worse, deal with related resources using custom code for every scenario? With ActiveResource.js, you don’t have to.

F# is a strongly typed, multi-paradigm programming language with imperative, functional, and object-oriented programming methods.

In the first part of our F# tutorial series, Toptal Freelance Software Engineer Shanglun Wang demonstrates how to get started and create a simple app using nothing but F#.

Magento is an extremely popular eCommerce platform used by businesses of all sizes, so what can we do to make it faster and more efficient? In this article, Toptal Freelance Magento Developer Paul Mestereaga explains what you can do to improve the performance of your Magento site.

JavaScript is an oddball of a language with numerous approaches to almost any problem. When ES6 added the “class” keyword, did it save the day or just muddy the waters? In this article, Toptal Freelance JavaScript Developer Justen Robertson explores OOP in modern JS.

The whole point of smart contracts is that they need to be more secure and efficient than traditional contracts. So where do smart contract oracles fit in?

In the final installment of our three-part series, Toptal Blockchain Developer John R. Kosinski explains the role of oracles in the evolution of trust.

Node 8 has brought significant performance and feature upgrades. Should you use it on new projects? Is it worth upgrading existing codebases? In this article, Toptal Freelance JavaScript Developer Youssef Sherif gives a tour of Node 8’s biggest changes and what they mean for your project.

Solidity is the programming language of choice for Ethereum and the de facto industry standard for smart contract development.

In the second article of our three-part series, Toptal Blockchain Developer John R. Kosinski takes a closer look at Solidity quirks and features, explaining how to make the most of it.

If you’re searching for the holy grail of bug-free code in JavaScript, Python, Ruby, Swift, and/or Scala, look no further! This monad tutorial by Toptal Freelance Functional Programmer Alexey Karasev takes you from category theory to the practical implementations of the Option/Maybe, Either, and Future monads, plus a sample program—in all five languages.

Oracles are changing the way we view and create smart contracts. How do we implement them in Ethereum, using nothing but Solidity and standard dev tools?

In the first article of our three-part series, Toptal Blockchain Developer John R. Kosinski explains how to get started and compile a smart contract with oracles.

The humble ERC20 token specification has become the de facto standard for Ethereum tokens. If you come across an Ethereum smart contract, chances are it’s ERC20-compliant.

In this guide, Toptal Freelance Ethereum Developer Gilad Haimov demonstrates how you can create and deploy your own ERC20 token in under an hour.

The existence of RESTful APIs is a popular myth in web development—but it’s a myth we can work with. The right tools can help keep documentation consistent and streamline automated testing. In this article, Toptal Freelance JavaScript Developer Alexander Zinchuk explores several time-saving approaches to developing REST APIs, with examples in Node.js and Ruby on Rails.

Manually gathering information about user-generated data is time-consuming, to say the least. That’s why more organizations are turning to automatic sentiment analysis methods—but basic models don’t always cut it. In this article, Toptal Freelance Data Scientist Rudolf Eremyan gives an overview of some sentiment analysis gotchas and what can be done to address them.

The Raspberry Pi is a little computer that you can get for as low as USD $5 and on which you can run many different types of software and build many different projects. In this article, I’m going to guide you through the process of setting it up as a home development server and deploying a full-stack JavaScript application that you can access from outside your network. This is great for setting up your own remote digital workspace, or simply to have control over the hardware you use for development.