Migrate Railway app: FastAPI

Move FastAPI compute from Railway 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: Export variables from the Railway service (Variables tab or railway variables) into an env file kept out of the repository. Not migrated automatically: Railway cron schedules, volumes and private networking are not migrated; persistent data belongs in a managed database, a bucket or an Ample volume. Cutover: Add the custom domain with ample domain add, update DNS from the Railway target, keep the Railway service until verified, then remove it. Rollback: keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

Workflow Steps

1. Inventory the source: List what Railway app provides beyond the component you are moving. Out of scope here: Railway cron schedules, volumes and private networking are not migrated; persistent data belongs in a managed database, a bucket or an Ample volume.

2. Source step 1: Export variables from the Railway service (Variables tab or railway variables) into an env file kept out of the repository.

3. Source step 2: Translate railway.json/Nixpacks settings into the repository's build and start commands; Ample detects Node and Python builds itself.

4. Source step 3: Note Railway-only features in use: cron schedules, volumes, private networking, templates.

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, update DNS from the Railway target, keep the Railway service until verified, then remove it.

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 Railway 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: Railway cron schedules, volumes and private networking are not migrated; persistent data belongs in a managed database, a bucket or an Ample volume.

Cost Estimate

Monthly Amount: $10.00 Basis: Size prices from pricing.toml (loaded by the API)

• Components:
  • App server: s-1vcpu-1gb x1.0: $5.00
  • Managed PostgreSQL database: s-1vcpu-1gb x1.0: $5.00 Note: Destination always-on monthly price of the tested sizes; apps auto-pause when idle.

Evidence Summary

Destination side verified: the FastAPI pattern fixture deployed on Ample and its checks passed. The source-side export from Railway 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: GET /v1/catalog
• Search published recipes by intent, stack and constraints: POST /v1/catalog/search
• Prepare a side-effect-free deployment plan for an authorized project: POST /v1/catalog/plan
• Read the existing agent authentication setup: GET /mcp/setup
• Browse Railway app: GET /v1/catalog/nodes/migration%3Arailway-app
• Browse FastAPI: GET /v1/catalog/nodes/stack%3Aframework-fastapi
• Browse Migrate compute: GET /v1/catalog/nodes/intent%3Amigrate-compute.