Quotas, Limitations, and Technical FAQ

Quota Limits

The following are the quota for users based, stratified by the three Subscription Plans offered by Fermyon Cloud:

* Signifies a resource that is not an explicit line item in the Fermyon Cloud Subscription Plan but is eligible for a quota increase for Growth and Enterprise Plan users who can reach out to Fermyon team for assistance.

Starter PlanGrowth PlanEnterprise Plan
Application Quota
Spin application count5100Contact us
Spin application package size (MB)*100100Contact us
Spin application deployments per minute*1010Contact us
Request handler duration (seconds)*1010Contact us
Rate Limiting Quota
Request execution count100,0001,000,000Contact us
Request executions per second*1,0001,000Contact us
Spin application deployments per hour*100100Contact us
Outbound requests per hour per Spin app*500500Contact us
Custom domains *5100Contact us
Custom Fermyon subdomain character count*6262Contact us
Bandwidth egress (GB)550Contact us
Key value store key size (bytes)*255255Contact us
Key value store value size (MB)*11Contact us
Key value store storage size (GB)12Contact us
Key value maximum keys*1,0241,024Contact us
SQLite StorageSee private beta documentationSee private beta documentationSee private beta documentation
Region count11Contact us

Known Limitations

Fermyon Cloud Limitations

  • A custom Fermyon subdomain must be unique
  • A user can execute a maximum of 3,000 requests per hour toward the Cloud API. This includes API requests from the CLI (spin) and navigating the Fermyon Cloud website.
  • The device and browser token lifetime for Fermyon Cloud Dashboard authentication is 7 days
  • A Spin application can have a maximum of 1 key value store

Spin Limitations

Fermyon Cloud supports Spin CLI v0.6.0 or newer. That being said, there are certain Spin SDK triggers and APIs that are not yet supported on Fermyon Cloud. Please review the table below to see what is supported today on Fermyon Cloud:

FeatureSDK Supported?
RedisNot supported
Outbound HTTPSupported
Configuration VariablesSupported
Key Value StorageSupported (only default store)
SQLite StoragePrivate Beta
Serverless AIPrivate Beta
Outbound RedisSupported
Custom TriggersNot supported

To learn more about what feature support looks like for various programming languages, visit the Spin Language Support Guide.

Other Limitations

Technical Frequently Asked Questions

  • Why do I see mixed replies from my service during an upgrade?
    • When doing an upgrade of an application, there is a gradual roll-out happening. This means that requests will hit both the existing and new modules, as the upgrade completes. You will see a pattern like the one below, showing the body reply from an HTTP request:
11:08:13 : Hello from Rust
11:08:18 : Hello from Rust - updated
11:08:19 : Hello from Rust
11:08:23 : Hello from Rust - updated
11:08:24 : Bad Gateway
11:08:26 : Hello from Rust - updated
11:08:27 : Bad Gateway
11:08:29 : Hello from Rust - updated
  • Q: It’s been over 72 hours and my custom domain hasn’t successfully verified, now what?

    • If you’re a Growth or Enterprise plan user, please reach out to support@fermyon.com. Otherwise, please go to Discord’s #cloud channel for assistance.
  • Q: How do I add a new record?

    • At this time, you can only add a maximum of 1 custom domain to your Spin application. We do not support additional records at this time. To file a feedback request, please visit github.com/fermyon/feedback.
  • Can I configure external DNS for my custom domain on Fermyon Cloud?

    • Fermyon Cloud only supports Fermyon DNS at this time for custom domains. To file a feedback request, please visit github.com/fermyon/feedback.
  • Unable to redeploy an app on Fermyon Cloud?

    • If spin deploy fails with the error No channel with app_id xxxx and name spin-deploy, but the app works locally (via spin build --up), please delete the app from your Fermyon Cloud dashboard and try again.

Next Steps

  • Learn how to engage with Fermyon to get support