Cara's web and mobile app, a platform for artists, combines the experience of Instagram and X. It provides a space for users to showcase their portfolios and share updates on their feeds. The app's serverless backend, powered by Vercel Functions, recently incurred a significant cost of $ 98,280 due to a sudden surge in usage.
The sudden surge in app usage can be attributed to many artists migrating from Meta, primarily due to their discontent with its AI policies, to Cara, an AI-free social platform. Cara's user base skyrocketed from 40,000 to 650,000 in just a week. Meta's use of public posts for AI training, with only European users having the option to opt-out under GDPR laws, has been a primary source of dissatisfaction.
Vercel Functions is a serverless computing service provided by Vercel, a platform for deploying front-end projects. With Vercel Functions, developers can run server-side code, which allows them to create and deploy small, single-purpose functions that scale automatically and are billed based on usage. Vercel Functions is designed to support efficient and scalable backend operations for web and mobile applications, making it easier for developers to focus on building and deploying their applications without managing infrastructure – thus, a serverless offering.
Founder Jingna Zhang of Cara discovered that using Vercel to host her platform became costly as the number of users increased. On X, Lee Robison, head of product at Vercel, explains:
To provide a little more detail, your function usage spiked at 56 million function invocations per day on June 3 after the Cara app was rising in the App Store. Looks like your mobile app is consuming the API which is deployed to Vercel.
Various responses came from the community regarding Cara's serverless approach. On a Reddit thread, a respondent commented:
There’s a point where serverless ceases to be the most cost-effective approach. Few of us will get to that level, and those who do are likely facing a "good" problem, but at some point, you need to start looking into Kubernetes and running your own infrastructure. I don’t recommend this for early-stage work, but knowing it’s on the radar as a cost-saving measure is critical.
And Yan Cui, a serverless AWS Hero, tweeted:
Another Vercel billing surprise...
People are already extrapolating this and equating it to "serverless is expensive" :-(
If you have an architecture capable of succeeding as they need, it'll cost you if you weren't architected for success ahead of time.
We should acknowledge that pay-per-use pricing is more expensive at scale. But Vercel's over-usage pricing is insane!
This is not the norm with most serverless platforms.
Lastly, in a LinkedIn post, Gergely Orosz suggested that to cover increased costs, the app should add ads or introduce a paid membership with extra benefits, considering its large user base. Alternatively, the app could slow its growth, keep it smaller, or change its infrastructure to manage costs better, though this would require additional development work.