Notion's Recipe for High-Velocity Web Experimentation
Notion's website team faces a distinctive challenge: how to communicate a platform that spans everything from personal travel planning to enterprise knowledge management. With millions of diverse visitors arriving each week, the marketing site must resonate across that entire spectrum—and the team needs to iterate and test relentlessly to make that happen.
The solution involved moving from ECS to Vercel, integrating Statsig for feature management, and leaning into edge-level execution. The result: hotfix deployment time dropped from one hour to 15 minutes (a 75% decrease), rollbacks happen in seconds, and the site now maintains an average Cumulative Layout Shift score of 0.09 or better.
Shifting From Infrastructure Management to Iteration
Before the move, Notion ran its marketing site on ECS. But the team is made up of web experience specialists, not infrastructure engineers, and the overhead of handling traffic spikes, autoscaling, and slow deployments was eating into iteration time. Vercel removed that burden entirely.
With infrastructure maintenance abstracted away, the team now leans on fast deploys and Instant Rollbacks to push changes quickly and revert them just as fast when needed. What once took an hour for a hotfix now takes just 15 minutes, and rolling back a change happens in seconds.
Edge-Based Experimentation With Minimal Payload
Notion’s marketing sites are built with Next.js and connected to Statsig for experimentation. The integration pushes experiment updates automatically to Vercel's Edge Config store. Middleware then makes routing decisions at the edge, with the Statsig SDK bootstrapped directly from Edge Config rather than making a separate request to the Statsig API.
Keeping experiments server-side minimizes payload sizes and latency, so running tests doesn't drag down Core Web Vitals. The consistent CLS scores at 0.09 or better reflect that approach.
Feature Flags Built Into the Workflow
The Vercel Toolbar's integrated feature flag controls let both engineers and non-engineers toggle experiments without leaving the preview environment. Notion's marketing team uses these flags to run tests targeting top-of-funnel growth, specifically focusing on increasing the number of new onboarded users.
Experimentation is deeply rooted across Notion's broader team, with hundreds of tests run per year. The combination of Statsig and Vercel gives them seamless integration and holistic metric analysis—top-line performance numbers alongside detailed views of how each flag is behaving.
Keeping Performance in Check
Constant experimentation requires constant vigilance. Notion uses Vercel's monitoring tools to track site-wide performance and resolve issues as they arise. Weekly queries and ad-hoc dashboards help the engineering team watch metrics like page errors and caching issues, ensuring experiments don't compromise the user experience.
The overall impact since adopting Vercel: fewer infrastructure concerns, faster deployments, and more time spent iterating on the kind of updates that actually connect with users.
