Migrate Vercel app: FastAPI

Move FastAPI compute from Vercel app to Ample, one component at a time. Destination verified on Ample: the app built, started and answered on its public HTTPS URL with encrypted configuration delivered. Source procedure: Copy environment variables from the Vercel project settings (or vercel env pull) into an env file you keep out of the repository. Not migrated automatically: Edge middleware, ISR revalidation, image optimization, cron jobs and Vercel integrations are not migrated and are unverified on Ample. Cutover: Add the custom domain with ample domain add, set the documented DNS records, keep the Vercel deployment until traffic is verified, then remove the domain from Vercel. Rollback: keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

Representative Queries:

• Migrate Vercel app: FastAPI
• Where can I host FastAPI built with FastAPI?
• I need a component-scoped export/import or reconfiguration procedure for FastAPI, with compatibility checks, verification and rollback.

Prerequisites:

• Authorized access to the Vercel app source and its export tooling
• An inventory of every component in scope and out of scope
• A validated backup or copy before any cutover
• An Ample account token with servers:write, databases:read

Workflow Steps:

1. Inventory the source: List what Vercel app provides beyond the component you are moving. Out of scope here: Edge middleware, ISR revalidation, image optimization, cron jobs and Vercel integrations are not migrated and are unverified on Ample.
2. Source step 1: Copy environment variables from the Vercel project settings (or vercel env pull) into an env file you keep out of the repository.
3. Source step 2: Note the framework preset, build command and output directory; Ample detects the same from the repository.
4. Source step 3: List Vercel-only features in use: edge middleware, ISR revalidation, image optimization, cron jobs, integrations.
5. Deploy on Ample in parallel: pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template. Pass the exported variables with --env; keep the source running. Command: ample deploy . --name --public --start "python3 run.py" --env-file .env.production.
6. Validate before cutover: Run the app's own checks and, for data, compare counts and checksums; the example checks are the pattern self-tests (/p/configuration-secrets, /p/relational-records).
7. Cut over: Add the custom domain with ample domain add, set the documented DNS records, keep the Vercel deployment until traffic is verified, then remove the domain from Vercel.
8. Rollback: Point DNS or configuration back to the source. The source was never modified; deletion is a separate, user-executed step after validation.

Examples:

• FastAPI pattern fixture (destination): Verified destination basis: FastAPI compute.

Success Checks:

• Destination app responds on its public URL
• Configuration-secrets check from the destination example
• Relational-records check from the destination example
• Data or object counts and checksums match the source.

Limitations:

• Documentation only: nothing is executed automatically and no execution binding is offered.
• The source-side procedure is documented from Vercel app's standard tooling and was not executed in this catalog's evidence; the destination side was verified with the pattern fixture.
• No full source-product parity is claimed: Edge middleware, ISR revalidation, image optimization, cron jobs and Vercel integrations are not migrated and are unverified on Ample.
• Verified on the python-3.12 template at s-1vcpu-1gb; region, compliance and request-duration limits are unknown.

Cost Estimate:

• Monthly Amount: $10.00 (USD)
• Components:
  • App Server (s-1vcpu-1gb): $5.00
  • Managed PostgreSQL Database (s-1vcpu-1gb): $5.00
• Note: Destination always-on monthly price of the tested sizes; apps auto-pause when idle. Source costs are unknown to Ample.

Evidence Summary:

• Summary: Destination side verified: the FastAPI pattern fixture deployed on Ample and its checks passed. The source-side export from Vercel app is documented from the vendor's standard tooling and was not executed by this catalog's evidence.
• Last Verified At: 2026-09-21T01:14:18Z

Next Actions:

• Browse the catalog index
• Search published recipes by intent, stack and constraints
• Prepare a side-effect-free deployment plan for an authorized project