Super apps are pushing the limits of System Design

Building a comprehensive digital ecosystem that brings together messaging, payments, ride-hailing, and e-commerce is no small feat. These all-in-one platforms — often called super apps — bundle multiple services into a single application to give users the convenience of “everything in one app.”

Super apps like WeChat, Grab, and Paytm demonstrate what it takes to scale such platforms while keeping them resilient and maintainable. Behind the seamless experience lie complex engineering choices that keep services modular yet integrated to maintain data consistency across domains. These choices also enforce strong security while still enabling innovation.

In this newsletter, we'll break down the engineering principles that power these massive platforms. We will explore how super apps tame complexity, deliver a unified user experience, and safeguard enormous volumes of data globally. We will also uncover the architectural pillars that allow continuous growth and adaptation, offering practical lessons you can apply in your System Designs.

Let’s begin!

Architectural foundations for super apps#

Super apps combine payments, messaging, ride-hailing, and many other services in a single ecosystem. Supporting such variety requires an architecture that is both modular and resilient. A monolithic structure quickly becomes unmanageable, leading to slower releases and higher risk. That’s why many platforms eventually adopt microservicesAn architectural approach where a complex application is composed of small, independent services, each running in its own process and communicating with others via lightweight mechanisms, typically APIs., where each core service can be built, deployed, and scaled independently while keeping failures contained. Some super apps, like early versions of WeChat and Paytm, began with monolithic or layered architectures, and then gradually migrated toward microservices as they scaled.

These microservices also support mini-apps, which are lightweight extensions that plug into the platform to add new functionality. Enabled by a plugin-driven architectureA software design pattern where core functionalities are extended and customized through external, independently developed and loadable components (plugins), allowing for dynamic addition of features without modifying the core system., mini-apps can be built by first—or third-party developers—and tap into the super app’s infrastructure and user base. While this approach increases flexibility, it also brings distributed system challenges such as data consistency and inter-service latency.

The illustration below depicts how a super app leverages a plugin-driven microservices architecture:

Having explored super apps and their fundamental architecture, we can now consider how organizations decide which apps to combine into a super app.