Just another (Black) Friday

• 80% year-over-year increase in revenue

• 2x higher conversion

• Zero downtime

• Core Web Vitals shift from red to green

Their success came from deliberate performance decisions, not SREs on standby reacting to outages.

Link to headingDefense that adapts to traffic

At scale, security is as much about maintaining control as it is about protection. The same global network that keeps pages fast also shields them from attacks, automatically absorbing and filtering traffic before it reaches the origin.

Every request goes through a multi-layered firewall, and for Vercel customers, this means the platform firewall has already deflected the largest DDoS attempts long before they reach their apps.

Last year, Vercel's system Firewall triggered 3,052,195,860 request blocks, while our customer-specific Web Application Firewalls blocked 519,841,270 requests.

Platform Firewall for DDoS
Vercel’s Firewall automatically mitigates distributed denial-of-service traffic by filtering requests at the network perimeter. The system dynamically scales its defenses as load increases, so legitimate users continue to see a fast experience even during an attack.

Business logic and the Vercel Web Application Firewall
The Vercel WAF gives teams granular control to apply their own logic at the edge. Instead of static rules, the WAF lets customers define protection around business-critical routes such as checkout, login, or API endpoints. This ensures security is specific to the application, not generic to the network.

Keeping the experience human
Poorly configured bot defenses, or asking your customers to pay traffic light tax, can create friction when traffic spikes. BotID provides invisible CAPTCHA-level protection that automatically distinguishes real usrs from automated agents, without degrading UX.

Link to headingServe instantly, update intelligently

At high traffic, the goal is not just speed but predictability and origin stability. The CDN must adapt: serve from cache when possible, refresh intelligently, and collapse redundant work. Below are key techniques Vercel uses to achieve this.

Revalidation that is invisible to users
Rather than forcing every user to wait for rebuilds, Vercel supports background revalidation. Pages served stale will trigger regeneration behind the scenes while users still get a fast response.

This means a page may refresh every 5 minutes, but users never see that pause.

Request collapsing to prevent stampedes
When many requests hit an uncached or expired route at once, Vercel’s CDN collapses them into a single regeneration per region. Other requests wait and receive the result. This prevents duplicate work and protects the origin under traffic surges.

Link to headingTrack performance & availability in real time

While many companies may insist on a code freeze, Vercel customers didn't stop deploying, with 2,454,917 deployments taking place over this roughly 96 hour window.

To stay confident during peak traffic, you need full visibility into how your system behaves. Not after the fact, but while it’s running.

Observability gives you that insight: you can see latency, errors, cache behavior, and resource usage across every layer. On Vercel, that means monitoring everything from network requests to function invocations and real user metrics.

Built-in insights by layer

In the Observability dashboard, you can view metrics across these layers:

• Cache hit/miss rates, request count per region, traffic by path and bot category

• Vercel Function invocation counts, error rates, and latency

• Upstream latency and error rates to pinpoint third-party slowdowns

• Revalidation frequency and cache efficiency

• Real-user metrics aggregated over time to see how performance truly feels

Custom queries and anomaly alerts

You can write custom queries to investigate traffic, like sustained latency above threshold, error spikes, or rising cache miss rates.

Anomaly alerts, available for Pro and Enterprise users in public beta, can notify you at the earliest signs of unusual app activity.

Unified signal streams

Vercel lets you stream logs, traces, analytics, and performance data into your existing tools via Drains. You get correlated signal: a slow function call can be tied to a trace, enriched logs, and a decline in web vitals. This unified view helps you quickly root-cause regressions.

Link to headingGet ready for Black Friday with Vercel

Vercel’s global network absorbs traffic spikes, serves content from cache, and revalidates pages in the background. Built-in observability tracks performance and availability in real time so teams can monitor and adjust during peak load.

Make Black Friday just another fast, reliable day on your platform. Our team can help you validate your setup, apply the right protections, and optimize your caching strategy before traffic peaks.

Talk to sales to build a tailored readiness plan, or join our Black Friday Cyber Monday readiness webinar for a full walkthrough, best practices checklist, and a free site readiness assessment tool.