Fly.io vs Vercel
Front door check counts, what each vendor’s status page recorded and SLA terms for these vendors.
30-day window ending
Front door checks
Every 15 minutes we send a request to a documented endpoint for each vendor from a single CheckUpstream location and count the answers. A reachable front door does not confirm that a customer action worked.
| Last 30 days | Fly.io | Vercel |
|---|---|---|
| Front door reachableOut of checks with a clear answer |
|
|
Checks 15 minutes apart cannot see disruptions shorter than that. Each vendor is checked at its own endpoints, so the counts cover different things.
Fly.io · check scope
api.machines.devapi · No vendor region
Front door reachable in 2,879 of 2,879 checks with a clear answer, last 30 days, checked every 15 minutes from a single CheckUpstream location.
- First check in this window
- Latest clear answer
Vercel · check scope
api.vercel.comapi · No vendor region
Front door reachable in 2,879 of 2,879 checks with a clear answer, last 30 days, checked every 15 minutes from a single CheckUpstream location.
- First check in this window
- Latest clear answer
What each vendor’s status page says
Recorded starts in the same 30-day window, excluding maintenance. Vendors report incidents differently; fewer posts don’t prove better reliability.
| Last 30 days | Fly.io | Vercel |
|---|---|---|
| Incidents recorded | 11 | 4 |
| Recorded incident durationMedian | 1h 28m 9 valid durations | Too few dated records 4 valid durations |
Duration uses at least 5 incidents with vendor-supplied starts and recorded closure times. First-observed starts are excluded. A record may close when a post disappears or our tracking period expires; this does not confirm recovery. A missing closure time does not mean an outage is ongoing.
Fly.io says
Partial outage in AMS
- Started
- Closure
- Not recorded
Delayed ingestion of app logs
- Started
- Closure
- Not recorded
Network outage in AMS region
- Started
- Closed in record
Vercel says
Build failures and 500 errors for functions using Edge runtime
- Started
- Closed in record
Deployment stuck in initializing state
- Started
- Closed in record
Elevated Errors Triggering Deployments
- Started
- Closed in record
Check the terms for your plan
An SLA applies to specific products and plans. Credit eligibility also depends on exclusions, evidence and filing deadlines.