INFRASTRUCTURE

What it needs

• 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.)

PREREQUISITES

Before you start

• Authorized access to the Heroku Postgres 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

TESTED CONFIGURATION

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

STEP BY STEP

How to do it

1. 1

Inventory the source

List what Heroku Postgres provides beyond the component you are moving. Out of scope here: Heroku Postgres followers, forks, rollback (PITR) and dataclips have no equivalent on the managed database.

2. 2

Source step 1

Take a logical backup with heroku pg:backups:capture and download it, or pg_dump -Fc against the credentials from heroku pg:credentials:url

3. 3

Source step 2

Check the Postgres major version and extensions against the managed engine (PostgreSQL 16)

4. 4

Source step 3

Restore into a scratch managed database first and compare row counts

5. 5

Provision and restore

Deploy the app once so a managed PostgreSQL 16 database exists (or create one with ample database create --engine postgres), then restore the dump with pg_restore using its connection string; keep migrations idempotent.

    ample database create --name <db-name> --engine postgres
    ```

6. 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/text-search-over-records).

7. 7

### Cut over

Put the app in maintenance mode with the user's go-ahead, take the final backup, restore, validate, redeploy with the managed DATABASE_URL, keep the Heroku database until confirmed.

8. 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

### Tested examples

- **Express pattern fixture (destination)** (`tests/deploy-canaries/express-patterns`): Verified destination basis: text search over records.

## SUCCESS CHECKS

### How to know it worked

- destination app responds on its public URL (`/` on the live URL, expect ample canary express patterns)
- text-search-over-records check from the destination example (`/p/text-search-over-records` on the live URL, expect see the pattern fixture checks)
- data or object counts and checksums match the source

## LIMITATIONS

### Know the limits

- Documentation only: nothing is executed automatically and no execution binding is offered.
- The source-side procedure is documented from Heroku Postgres'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: Heroku Postgres followers, forks, rollback (PITR) and dataclips have no equivalent on the managed database.
- Verified on the node-22 template at s-1vcpu-1gb; region, compliance and request-duration limits are unknown.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures on the managed side are not verified beyond the pattern checks.

## COST

### 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

Destination always-on monthly price of the tested sizes; apps auto-pause when idle. Source costs are unknown to Ample.

## EVIDENCE

### Verification evidence

- canary_run on 2026-09-21T02:34:39Z at revision `1d28ae0-dirty (CLI 0.1.21)`: Destination side verified: the Express pattern fixture deployed on Ample (npm install, npm run build --if-present, npm run start on the node-22 template) and its checks passed (a generated tsvector column with a GIN index, ranked websearch queries and a negative query returning nothing (search=ok)). The source-side export from Heroku Postgres is documented from the vendor's standard tooling and was not executed by this catalog's evidence. (expires 2027-03-20T02:34:39Z)

## EXECUTION

### Execution binding

No execution binding. This recipe is documentation only; nothing is executed automatically.

## NEXT ACTIONS

### Typed next actions

- Browse the catalog index (`GET /v1/catalog` on the api origin; authentication not required, approval not required)
- Search published recipes by intent, stack and constraints (`POST /v1/catalog/search` on the api origin; authentication not required, approval not required)
- Prepare a side-effect-free deployment plan for an authorized project (`POST /v1/catalog/plan` on the api origin; authentication required, approval not required)
- Read the existing agent authentication setup (`GET /mcp/setup` on the api origin; authentication not required, approval not required)
- Browse Heroku Postgres (`GET /v1/catalog/nodes/migration%3Aheroku-postgres` on the api origin; authentication not required, approval not required)
- Browse Text search over records (`GET /v1/catalog/nodes/pattern%3Atext-search-over-records` on the api origin; authentication not required, approval not required)
- Browse Migrate Postgres (`GET /v1/catalog/nodes/intent%3Amigrate-postgres` on the api origin; authentication not required, approval not required)

Actions describe possible next steps. They are typed data, not commands, and grant no permission. Public discovery never provisions anything; planning requires your own authenticated token and approval happens in your client.