Toptal Engineering Blog

One of the new possibilities offered by Lambda@Edge is the ability to implement server-side A/B testing using Lambdas on CloudFront’s edge servers.

In this article, Toptal Full-stack Developer Georgios Boutsioukis guides you through the process and outlines the pros and cons of A/B testing with Lambda@Edge.

IMDb ratings have genre bias: For example, dramas tend to score higher. Removing common feature bias and keeping unique characteristics, it’s possible to create a new, refined score based on IMDb information.

The development of our lightweight programming language created in C++ is nearing completion and we can finally see it in action.

In the final part of our Stork series, Toptal Full-stack Developer Jakisa Tomic explains how to implement statements, tuples, and modules.

Developing a new programming language from scratch tends to create unique challenges, followed by unconventional solutions that may go against some programming dogmas.

In Part 3 of our Stork series, Toptal Full-stack Developer Jakisa Tomic elaborates on how C++ macros can help and why expression implementation might not be as straightforward as expected.

Toptal’s JavaScript Speed Coding Challenge invited creative solutions from the beginning. As the week played out, competitors got closer and closer to the maximum theoretical score. Then something unexpected happened…

Would you rather develop a statically or dynamically typed programming language? How would you devise your expression parser?

In the second part of our Stork series, Toptal Full-stack Developer Jakisa Tomic outlines his preferred approach and demonstrates how you can create a functional expression parser.

Did you ever consider creating your very own programming language, either as a result of necessity or professional curiosity?

In part one of our series, Toptal Full-stack Developer Jakisa Tomic takes the first steps toward creating a lightweight scripting language written in C++.

Cloud architects with the AWS Certified Solutions Architect - Associate qualification are in high demand, with good reason—the AWS exam sets the bar high. What’s the best way to prepare for it?

Tests should keep apps from being flaky. But tests themselves can become flaky—even the most straightforward ones. Here’s how we dove into a problematic test on a PostgreSQL-backed Rails app, and what we uncovered.

Supervised learning is the key to computer vision and deep learning. However, what happens when you don’t have access to large, human-labeled datasets?

In this article, Toptal Computer Vision Developer Urwa Muaz demonstrates the potential of semi-supervised image classification using unlabeled datasets.

Inspired by stale-while-revalidate cache control logic, modern sites implement stale-while-refresh logic on the UI side. Thankfully, React Hooks make this logic painlessly reusable across components.

Writing multiple native applications for different mobile platforms can be a daunting task, but taking a non-native approach comes with pitfalls of its own.

In this article, Toptal Mobile Developer Joel Frank outlines the concept of Write Once, Deploy Everywhere (WODE) and explains how to choose the right development path for your project.

The main artifact of all your work is most likely plain text files. So why don’t you use Notepad to create them? Find out how the Language Server Protocol can transform text editors into code editors, without coupling.

Shopping online is more convenient than ever, so how do you create an online marketplace tailored to cater to your specific needs?

In this article, Toptal JavaScript Developer Konrad Gadzinowski explores marketplace business models and payment methods for both regional and global services.

Internet privacy’s cutting-edge technology includes encrypted server name indication (ESNI) and encrypted DNS in the form of DNS over HTTPS (DoH). Find out what they are, why they exist, and how they work.

Markov Chain Monte Carlo (MCMC) methods let us compute samples from a distribution even though we can’t do this relying on traditional methods.

In this article, Toptal Data Scientist Divyanshu Kalra will introduce you to Bayesian methods and Metropolis-Hastings, demonstrating their potential in the field of probabilistic programming.