Back in July, Meta launched Threads, a text-focused social app. The timing of the launch was strategic, as it took place during a period of user limitations on Twitter. This resulted in Threads becoming a popular alternative, with a staggering 100 million accounts signing up in just 5 days, making it the fastest-growing app across all platforms.
Jesse Chen, the Engineering Manager of Threads, recently wrote a blog post and gave interviews discussing the challenges of the project. The short development timeline and the need to scale up to accommodate an unprecedented number of users were the main hurdles faced.
To start off, Threads began development in January with a small, agile team. They wanted to keep the project under wraps at first and gradually expand the team. Currently, there are 3 product managers, 1 designer, and approximately 60 engineers working on the project.
The development approach involved leveraging Instagram’s foundation to maximize efficiency. The backend was built using Django, incorporating data modeling, logic, and security systems, as well as server architecture. This approach allowed them to reuse components from Instagram. For the mobile apps, Swift was used as the primary language for iOS, while Android utilized Jetpack Compose. Initially, the features were limited to meet the scheduled launch date.
In June, the final version of Threads’ code was submitted to the app store, getting ready for the anticipated launch in July. Once the launch date was set, the core team, along with infrastructure engineers in 4 different cities, prepared to handle the incoming traffic. They utilized monitoring tools like ODS and Scuba.
The most challenging aspect they identified was managing the influx of followers when accounts with a significant number of followers joined Threads. They had to find a way to handle this unprecedented scale.
Despite the speed at which users signed up, with 1 million accounts in just 1 hour and reaching 30 million accounts on the first day, the well-established foundation of the Meta platform ensured the backend could handle the traffic without any issues.
Looking ahead, Threads’ future involves rapidly introducing new features and improving the backend to handle the specific scalability requirements. Additionally, as Threads initially announced its intent to support the ActivityPub protocol, a decentralized social protocol, future enhancements will involve incorporating that as well.
TLDR: Meta successfully launched Threads as a text-based social app, attracting 100 million accounts within just 5 days. The development team faced challenges with the short timeline and managing the unprecedented scale. Leveraging Instagram’s foundation, they utilized Django for backend development and Swift for iOS. Threads plans to continue expanding features and improving scalability, including integrating the ActivityPub protocol.