Toptal Engineering Blog

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...

For a successful natural language processing project, collecting and preparing data, building resilient pipelines, and getting "model ready" can easily take months of effort even with the most talented engineers. But what if we could reduce the data required to a fraction? In this article, we’ll cover how transfer learning is making world-class models open source and introduce BERT (bidirectional encoder representations from transformers). BERT is the most powerful NLP “tool” to date. We’ll explore how it works and why it will 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 a 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.

GraphQL is a domain-specific language for data query and manipulation by Facebook. It is meant to replace the de facto REST standard in API creation. In this article, Toptal Freelance GraphQL Developer Ioram Gordadze creates a GraphQL API from scratch, summarizing problems new GraphQL developers face. He also teaches us to rethink the standard methods used in REST APIs in a more GraphQL-friendly manner.