INFRASTRUCTURE

What it needs

• Compute: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)
• Postgres: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)
• S3-compatible object storage: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

Before you start

• An authorization check in the route handler (session, token or header) before any storage access
• pg reading DATABASE_URL and @aws-sdk/client-s3 reading the S3_* variables
• A private bucket (never ample bucket publish) and an auto-provisioned or supplied PostgreSQL database
• An Ample account token with servers:write, databases:read and buckets:read

Exactly what was tested

• build: npm run build --if-present
• install: npm install
• runtime: node
• size: s-1vcpu-1gb
• start: npm run start
• template: node-22

How to do it

1. 1

Authorize before touching storage

Return 401 for unauthenticated requests; never expose object keys or the bucket endpoint to the browser.

2. 2

Record metadata in PostgreSQL

Keep the owner, name and object key in a table so authorization decisions come from your data, not from the bucket.

3. 3

Store and stream through the app

PutObject on upload, GetObject on download, both server-side with the injected credentials.

ample deploy . --name <app-name> --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...

4. 4

Test both paths

An unauthenticated request must return 401; an authorized request must return the stored content.

5. 5

Verify

Fetch the live URL and run the success checks below. On failure read the build log, then the runtime log, fix the cause and deploy again; do not blind-retry.

ample logs <deployment_id> --kind build

Tested examples

• Next.js private files canary (tests/deploy-canaries/next-private-files): 401 without a token; private=ok with the token after a database write and a bucket round-trip.

How to know it worked

• unauthenticated request is rejected (/files/demo on the live URL, expect unauthorized)
• authorized request returns the private object (/files/demo?token=<token> on the live URL, expect private=ok)

Know the limits

• Verified on the node-22 template at s-1vcpu-1gb; other templates and sizes are not verified by this recipe.
• Region, compliance attestations and request-duration limits are unknown and not claimed.
• Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
• PutObject and GetObject with path-style addressing are verified; multipart upload, listing, presigned URLs and lifecycle rules are not verified.
• Bucket credentials are passed as encrypted environment variables; the catalog never creates the bucket for you (use ample bucket create).
• Storage is allocation-priced per bucket quota and capped by the account plan; the estimate below covers compute only.
• Authorization is application code; Ample does not provide managed end-user authentication.
• Streaming large files through the app is not verified; the fixture uses small text objects.

Cost estimate

Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).

• app server x1 s-1vcpu-1gb: 5.00 USD
• managed PostgreSQL database x1 s-1vcpu-1gb: 5.00 USD

Apps and managed databases auto-pause when idle; the estimate is the always-on monthly price of the tested sizes. Plan quotas and budgets apply.

Verification evidence

• canary_run on 2026-09-20T01:13:26Z at revision cc3d82057f1d5e9aa31f682cee71aabfbbbcaabe-dirty (CLI e3181f5): Next.js route handler that rejects unauthenticated requests with 401, records file metadata in an auto-provisioned managed PostgreSQL database, stores the bytes in a private bucket and streams them back only after authorization (private=ok). (expires 2027-03-19T01:13:26Z)
• canary_run on 2026-09-20T01:13:26Z at revision cc3d82057f1d5e9aa31f682cee71aabfbbbcaabe-dirty (CLI e3181f5): ample bucket create issued credentials; PutObject and GetObject succeeded through the public S3 endpoint; publish exposed the object through the CDN host with an ETag; unpublish and delete cleaned up. (expires 2027-03-19T01:13:26Z)

Execution binding

MCP tool ample_deploy (registry mcp:ample_deploy), schema hash 876465fce906da0c observed 2026-09-20T01:55:48.667900+00:00 at revision 199ff1dfd526. Binding state at export: current. Required scopes: servers:write, databases:read, buckets:read.