A viral TikTok brought us 15,000 users overnight. Our servers crashed and we lost 80% of them.

Two weeks ago, a tech influencer with about 200k followers made a video about our app. He called it a "hidden gem" for freelancers, and the video blew up. By the next morning, we had 15,000 new signups.

I was ecstatic. I thought we had finally hit our breakout moment.

But by 10 AM, our database locked up. Our AWS instance couldn't handle the concurrent API requests. Users were getting 502 Bad Gateway errors when they tried to log in. My co-founder and I spent the entire day frantically upgrading our database tier and scaling our servers.

By the time the site was stable (about 18 hours later), the damage was done. I pulled the analytics this morning:

• Of the 15,000 signups, 12,000 never successfully logged in.

• Out of the 3,000 who did get in, most hit bugs because our notification service crashed and queued up 50,000 emails.

• We only retained about 50 active users from the entire viral event.

I feel sick. We had our one shot at virality, and we literally broke under the pressure. We were so focused on growth hacking and getting the word out that we never load-tested our infrastructure. We didn't have caching, our database was unoptimized, and our onboarding flow required 4 manual API calls just to render the dashboard.

Now our traffic is back to normal, but we wasted a massive free marketing opportunity that we might never get again.

For founders who have experienced a traffic spike: How do you prepare your infrastructure for sudden virality without overpaying for massive servers you don't need yet?

Do you use serverless architecture? Do you just accept that you might crash? I need to figure out how to make our system bulletproof before we try to push any more marketing.