# SvelteKit on Fly.io

Canonical: https://inetgeek.com/stacks/sveltekit-on-fly-io/

Fly.io publishes its own guide for deploying SvelteKit.

Svelte application framework that targets different deployment platforms through adapters.

## What SvelteKit needs

Every host claims to run SvelteKit, so the claim on its own decides nothing. These are the things SvelteKit requires from the platform underneath it, and what Fly.io publishes about each. Fly.io documents 2 of the 4.

| Requirement | Fly.io | Why it matters |
| --- | --- | --- |
| Max request duration | Not documented | SvelteKit load functions and form actions run on the server per request, bounded by this ceiling. |
| Edge network | Limited | The adapter decides where handlers run. An edge network is what makes the edge adapters worth choosing. |
| Build allowance | Not documented | Prerenderable routes are resolved at build time, so build allowance scales with the size of the site. |
| Scales to zero | Supported | Adapter output is usually a function per route. Scaling to zero removes idle cost at the price of a cold start. |

- Edge network source: https://fly.io/docs/reference/architecture/
- Scales to zero source: https://fly.io/docs/launch/autostop-autostart/

## What Fly.io documents

> Before you can deploy your SvelteKit app, you need to adapt it for your deployment target.

Source: https://fly.io/docs/js/frameworks/svelte/

### SvelteKit features on Fly.io

- **node_adapter**: Supported — In this example, to deploy your app on Fly.io, we'll install the Node Adapter. You can install it by executing the command ([source](https://fly.io/docs/js/frameworks/svelte/))
- **dockerfile_deploy**: Supported — That file can be automatically generated with fly launch. This command will also generate a Dockerfile for deployment. ([source](https://fly.io/docs/js/frameworks/svelte/))

## What it costs to run there

|  | Fly.io |
| --- | --- |
| Pricing model | Usage-based, no compute plan tiers; billing is pro-rated for the time resources are provisioned. |
| When you exceed a cap | No plan cap to exceed — Fly bills per second for provisioned resources. The only documented enforcement is unspecified automated scaling limits, which surface as an error message (platform-wide, all plans) |
| Regions | 17 regions |

- Pricing model source: https://fly.io/docs/about/pricing/
- When you exceed a cap source: https://fly.io/docs/about/pricing/
- Regions source: https://docs.fly.io/reference/regions/

## Whether it suits you

Workloads that ship as Docker images and need placement in particular regions. Billing is purely usage-based with no plan tiers, which suits spiky or region-pinned traffic better than a flat monthly fee.

Consider something else if: You want a predictable flat bill rather than charges that track the resources provisioned for each app.

Written by Palash Bagchi on 2026-09-05. This is a recommendation, not a sourced fact — it carries no citation because it is an opinion.

## Related

- Best hosting for SvelteKit: https://inetgeek.com/stacks/sveltekit/
- Fly.io: https://inetgeek.com/hosting/fly-io/