Guides · When your app is down
Your app is down. What to check, in order.
Someone tells you the app isn’t loading. Before you ask your AI to rewrite anything, work down this list. Most outages of apps built with AI have one of a handful of causes, and the error page usually says which.
1. Is it down for everyone?
Open the app on your phone with Wi-Fi off. Ask someone elsewhere to try. Or run the free launch check: it loads your app from Vigilia’s servers and tells you whether it answered, how fast, and whether the certificate is valid. If it loads for everyone but one person, the problem is on their side.
2. Read what the browser shows
| What you see | What it usually means |
|---|---|
“This site can’t be reached”, DNS_PROBE_FINISHED_NXDOMAIN | Your domain: it expired, or its DNS records changed. Check your registrar. |
“Your connection is not private”, NET::ERR_CERT_DATE_INVALID | The security certificate expired or doesn’t cover this address. Usually your host renews it, unless the domain’s DNS no longer points at the host. |
| Your host’s own “not found” or “deployment not found” | The site was unpublished, the custom domain was disconnected, or the project was paused or removed. |
| 500, 502 or 503 | The server behind the app is failing: your host, or a backend function that runs on every page. |
| A blank white page | The app crashed while starting, often on a missing environment variable. Open the console: see blank page in production. |
| The page loads, the data doesn’t | Your backend or database: an outage, a paused project, a quota, or a database rule. |
3. Is it one of your providers?
Your app depends on a host, a database and a few services. Check their status pages before anything else:
- Supabase · Vercel · Netlify · Cloudflare · Firebase
- Stripe · OpenAI · and your builder’s own status page.
If one of them is down, there is nothing to fix in your code. Tell your users, and wait.
4. Did you just publish?
If it broke right after a change, put the last working version back first and fix forward calmly. Your builder keeps a version history, and hosts such as Vercel and Netlify restore a previous deploy in a click. Then look at what changed, with the error in hand.
5. Is the database asleep or out of room?
Supabase pauses projects on its free plan after seven days of low activity, and sends a warning email about a week before. A paused project refuses every request until you choose Resume project in its dashboard. Free plans everywhere also have quotas: storage, requests, function calls. Hitting one can look exactly like an outage.
6. Is a bill unpaid?
An expired card on your host, database or domain registrar can suspend the service or let the domain lapse. Search your inbox for their emails.
7. Tell people
A one-line message (“we know, we’re on it”) on a status page or your social channels saves you a dozen support emails, and earns trust. Vigilia gives every app a free public status page with 90 days of uptime history, at getvigilia.com/status/your-app.
Next time, hear about it first
- Uptime checks: Vigilia checks your app every 5 minutes on Free and every minute on paid plans, where it can also open key pages such as checkout or sign-in and check they show what they should.
- Expiry warnings: your certificate is checked daily and your domain’s registration weekly, so neither runs out by surprise.
- Context: when it does go down, the incident says whether a provider you depend on was having an outage at the time, or whether it started right after a deploy.
Know before your users tell you
Vigilia watches your live app, explains what breaks in plain language, hands your AI the fix, and confirms it held with real visitors. One app is free.
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Questions
Why does my Supabase project say it is paused?
Supabase pauses projects on its free plan after seven days of low activity. Open the project in the Supabase dashboard and choose Resume project; it then answers requests again.