Posted by Chiko Shimizu, Developer Advocate, and Tamao Imura, Developer Marketing Manager
With Mercari, millions of people can buy and sell almost anything. The company was founded in Japan in 2013 and is now the largest C2C marketplace for smartphones in Japan. Mercari’s Client Architect team started using Jetpack Compose in 2020 with the aim of using modern solutions and technologies that are scalable over the long term to build their tech stack for new applications.
What they have done
The Mercari team had to implement a design system with complex status management and design in Android views – a very complex task. With Jetpack Compose they could not only implement this complex system, but also spend less time developing the individual screens.
Jetpack Compose also helped the team write UI code for their new app using the design system, which made the UI code precise and easy to understand. As a result, the team can spend more time writing screens and business logic, such as hands-on support for the dark topic.
In addition, the Mercari team wrote a proof-of-concept tool to integrate Figma into the design system, which automatically generates UI code from the component designs. The team said this tool was easier to develop with Compose because of its declarative nature.
“Once Android developers get used to writing Jetpack Compose code, they don’t want to go back.” – Anthony Allan Conda, Android Tech Lead at Mercari
Between Jetpack Compose and their new design system, Mercari was able to use far less code to write screens. On screens with infinitely scrollable content – a common use case – the code was actually reduced by around 56%. As a result, they could write more screens in the same amount of time, giving them more time to write business logic and other pieces of code.
Plus, they could do more with the user interface itself, such as: B. Include animations and use intuitive APIs, e.g. Animated Visibility, Dissolve, and Animatable.
Mercari plans to continue using Jetpack Compose in its new application until its release. Your design system with the Android SDK written in Jetpack Compose is also designed for use with multiple applications in Mercari.
Learn more about Jetpack Compose.