## The short version

Build and start for a Phoenix app on Ample.

### WHAT WAS VERIFIED

Verified on Phoenix: the app built and started with the documented commands and answered on its public HTTPS URL. 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`.

## 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.)

## PREREQUISITES

### Before you start

- A Phoenix project (`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`)
- An Ample account token with `servers:write`

## 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

#### Deploy

Run the synchronous deploy once and read the result.
   
   ```
   ample deploy . --name <app-name> --public
   ```

3. 3

#### Verify

Fetch the live URL on the example; on failure read the build and runtime logs.
   
   ```
   ample logs <deployment_id> --kind build
   ```

## EXAMPLES

### Tested examples

- **Phoenix pattern fixture** (`tests/deploy-canaries/phoenix-patterns`): Verified build and start on Phoenix.

## SUCCESS CHECKS

### How to know it worked

- app responds on its public URL (`/` on the live URL, expect ample canary phoenix patterns)

## COST

### Cost estimate

Estimated 5.00 USD per month (size prices from `pricing.toml` at build revision `ca0b484a7a9957c573a88d3a32dc603c3c10135a`).

- app server 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`); for this guide: the app built and started with the documented commands and answered on its public HTTPS URL. (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`.

## 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 Phoenix (`GET /v1/catalog/nodes/stack%3Aframework-phoenix` on the api origin; authentication not required, approval not required)
- Browse Configure deployment (`GET /v1/catalog/nodes/intent%3Aconfigure-deployment` on the api origin; authentication not required, approval not required)
- Browse Public web service (`GET /v1/catalog/nodes/pattern%3Apublic-web-service` 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:guides:phoenix:build-and-start`. Revision r1.

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

Formats: [HTML](/content/guides/phoenix/build-and-start/index.html) | [Markdown](/content/guides/phoenix/build-and-start.md) | [JSON contract](https://api.ample.computer/v1/catalog/recipes/page%3Aguides%3Aphoenix%3Abuild-and-start)