## The short version

Deploy a CSV import tool built with Phoenix on Ample using the browser file uploads pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as `DATABASE_URL`, a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables.

### WHAT WAS VERIFIED

Verified on Phoenix: content-type and size validation that rejects disallowed files, an object written to a private bucket and a row linking the record to the object key (reject=ok upload=ok linked=ok).

## INFRASTRUCTURE

### What it needs

- [Compute](/content/discover/primitive/compute/index.html): verified (Apps run in isolated x86_64 Firecracker microVMs; sizes are the priced VM sizes.)  
- [Postgres](/content/discover/primitive/postgres/index.html): 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](/content/discover/primitive/s3-compatible-object-storage/index.html): verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

## PREREQUISITES

### Before you start

- A Phoenix project that builds and starts with the documented commands (mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs)  
- A PostgreSQL driver reading `DATABASE_URL` at runtime (auto-provisioned when omitted, or supplied with --env)  
- A bucket from `ample bucket create` with its credentials passed as encrypted `S3_*` environment variables  
- An Ample account token with servers:write, databases:read, buckets:read

## STEP BY STEP

### How to do it

1. 1

### Build and start

`mix deps.get`, `MIX_ENV=prod mix compile` and `mix release` in the builder, then the release bin script with `PHX_SERVER=true` on the elixir-1.18 template; `PORT`, `DATABASE_URL` and `SECRET_KEY_BASE` read in config/runtime.exs. The server must bind 0.0.0.0 on `PORT`.

2. 2

### Implement the pattern on PostgreSQL

The fixture's module implements browser file uploads: content-type and size validation that rejects disallowed files, an object written to a private bucket and a row linking the record to the object key (reject=ok upload=ok linked=ok). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. 3

### Wire object storage

Create the bucket(s), then pass endpoint, region, bucket and keys as --env values. Use path-style addressing. Keep private data in an unpublished bucket.

4. 4

### Deploy

Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.

```
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=...
```

5. 5

### Verify

Fetch the live URL and the pattern self-test route(s) (`/p/browser-file-uploads`) from the example; then run your own checks. On failure read `ample logs <deployment_id> --kind build` then `--kind runtime`.

```
ample logs <deployment_id> --kind build
```

## EXAMPLES

### Tested examples

- **Phoenix pattern fixture** (`tests/deploy-canaries/phoenix-patterns`): Multi-pattern Phoenix app whose browser file uploads module was checked live; the module is under `tests/deploy-canaries/_pattern-modules`.

## SUCCESS CHECKS

### How to know it worked

- app responds on its public URL (`/` on the live URL, expect ample canary phoenix patterns)  
- browser-file-uploads self-test (`/p/browser-file-uploads` on the live URL, expect reject=ok upload=ok linked=ok)

## COST

### Cost estimate

Estimated 10.00 USD per month (size prices from pricing.toml at build revision ca0b484a7a9957c573a88d3a32dc603c3c10135a).

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

Upper-bound monthly price of the tested sizes. Buckets are allocation-priced per quota and not included.

## EVIDENCE

### Verification evidence

- canary_run on 2026-09-20T23:45:31Z at revision `4d1511e574302f3904b75088bd4048a0975218b3 (CLI 0.1.21)`: Phoenix pattern fixture deployed on Ample (mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; `PORT`, `DATABASE_URL` and `SECRET_KEY_BASE` read in config/runtime.exs); checks passed for browser-file-uploads and configuration-secrets. Pattern proof: content-type and size validation that rejects disallowed files, an object written to a private bucket and a row linking the record to the object key (reject=ok upload=ok linked=ok). (expires 2027-03-19T23:45:31Z)  
- canary_run on 2026-09-20T23:45:31Z at revision `4d1511e574302f3904b75088bd4048a0975218b3 (CLI 0.1.21)`: The same Phoenix app deployed with a --release-command migration; the marker it created was readable after activation. (expires 2027-03-19T23:45:31Z)

## EXECUTION

### Execution binding

MCP tool `ample_deploy` (registry `mcp:ample_deploy`), schema hash `876465fce906da0c` observed 2026-09-22T00:31:22.774679+00:00 at revision `e6446ceea69b`. Binding state at export: schema_changed. Required scopes: servers:write, databases:read, buckets:read.

## 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 CSV import tool (`GET /v1/catalog/nodes/workload%3Acsv-import-tool` on the api origin; authentication not required, approval not required)  
- Browse Phoenix (`GET /v1/catalog/nodes/stack%3Aframework-phoenix` on the api origin; authentication not required, approval not required)  
- Browse Browser file uploads (`GET /v1/catalog/nodes/pattern%3Abrowser-file-uploads` on the api origin; authentication not required, approval not required)  
- Browse Deploy web app (`GET /v1/catalog/nodes/intent%3Adeploy-web-app` 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.

## ABOUT THIS RECIPE

### Identifiers and status

Recipe `page:recipes:csv-import-tool:phoenix:attachments`. Revision r1.

release **published** support **verified** execution **blocked (schema_changed: live tool schema differs from the recorded binding)**

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