Toptal Engineering Blog

Web applications are becoming more popular day by day with stable options like React.js, Angular, and Vue.js. However, a serious competitor may be on the horizon: Svelte.

In this article, Toptal freelance software developer Teimur Gasanov introduces Svelte, a new framework for building user interfaces. He does so by walking us through creating a common log-in form used by virtually every type of application.

Micro-frontend architectures decompose a front-end app into individual, semi-independent “microapps” working loosely together. This can help make large projects more manageable, e.g. when transitioning from legacy codebases.

Secure payment processing is a key prerequisite for any eCommerce operation. If it fails, the consequences can be catastrophic for any company, big or small.

In this article, Toptal Ruby on Rails Developer Henrique Reinaldo Sarmento outlines how you can create a Ruby on Rails eCommerce app, leveraging PayPal and Stripe for reliable and secure payments.

Unwanted AI bias is already a widespread problem. Machine learning models can replicate or exacerbate existing biases, often in ways that are not detected until release. So what can be done about it?

Functional Programming is a paradigm of building computer programs using expressions and functions without mutating state and data.

In this article, we will talk about doing functional programming using JavaScript. We will also explore various JavaScript methods and features that make it possible. In the end, we will explore different concepts associated with functional programming and see why they are so powerful.

WordPress developers spent years struggling with sub-optimal solutions for CI/CD. Despite the fact that they were using the most popular CMS on the market, they often had to improvise and resort to time-consuming practices.

In this article, Toptal WordPress Developer Alexa Green shares her approach to WordPress deployment using Bitbucket and some straightforward code.

The successor of the revolutionary ESP8266, the ESP32 is a next-generation microcontroller. Find out how to sample its analog-to-digital converter (ADC) from a timer interrupt using the Arduino IDE.

We reduce boilerplate with common OOP patterns, but often, the code overhead of using patterns is almost the same—if not bigger—than if we’d used boilerplate code in the first place.

In aspect-oriented programming tutorial, we implement two functions (aspects) that allow for generic database connection management and caching. These allow us to mark methods that, when called, will automatically have the required functionally present in through IL weaving.

Pattern matching is a powerful tool commonly found in functional programming languages. The Ruby 2.7 release is going to include this feature.

In this article, Toptal Ruby Developer Noppakun Wongsrinoppakun provides a breakdown of what this addition will include and why it matters.

Single sign-on is great for users, sparing them from memorizing yet another password; for businesses, removing frictio; and for developers, since less code means less things that can go wrong.

In this Flask login tutorial, we’ll write a step-by-step guide to add a SSO login button into a Flask application with SimpleLogin and Facebook as an identity provider.

Most websites today rely on CSS to deliver more style and polish, but the sheer popularity of CSS is causing many people to take it for granted and overlook its importance.

In this article, Toptal UI Developer Silvestar Bistrović explains this disconnect and outlines why you need a true CSS specialist rather than a jack of all trades.

Migrating in either direction between Microsoft SQL Server and Oracle Database? There are some significant pitfalls to be aware of…

Data collection and preparation slow down traditional NLP projects. However, transfer learning and BERT can reduce the amount of data required and change the way companies execute NLP projects.

In an age of continuous delivery, Java developers have to be confident that their changes don’t break existing code, hence automated testing. There’s more than one valid approach to it, but how can you keep them straight?

Nearly every app requires an authorization system on top of an authentication system. We often need a fine-grained permissions model to allow only specific users to access certain resources while simultaneously restricting access for everyone else.

In this tutorial, Toptal Freelance Firebase Developer Joaquin Cid teaches how to build just such a system. Called role-based authentication, we’ll learn how to implement this system in an API using Node.js and Firebase.

Subscription-based apps need a special approach when it comes to analytics. Learn how a variation on the traditional sales funnel helps you work with LTV, subscriber retention, and churn rates to make your app better—and more profitable.