Apply database schema changes for Astro | Ample
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.)
PREREQUISITES
Before you start
- A migration command that reads DATABASE_URL and exits non-zero on failure
- A PostgreSQL database (supplied or managed)
- An Ample account token with servers:write and 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
- Write an idempotent migration
Create tables and markers with IF NOT EXISTS or a migration framework so a re-run is safe.
- Deploy with the release command
Ample runs the command before activation; a non-zero exit fails the release.
ample deploy . --name <app-name> --public --release-command "node migrate.cjs"
- Verify the marker through the app
Serve a route (/migrated) that reads something only the migration creates.
- 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
EXAMPLES
Tested examples
- Astro release-command canary (
tests/deploy-canaries/astro-postgres-app): node migrate.cjs runs before activation against the auto-provisioned managed database.
SUCCESS CHECKS
How to know it worked
- migration marker is readable (
/migratedon the live URL, expect migrated=release-ok)
LIMITATIONS
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.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
- Apps and their managed databases are placed together; cross-node shared databases are unsupported.
- The release command runs once per release on the app VM; there is no separate migration runner or rollback of a partially applied migration.
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
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.
EVIDENCE
Verification evidence
- canary_run on 2026-09-20T01:42:25Z at revision
199ff1dfd52683832ae75d3f98b53a7a4bff7f96-dirty (CLI e3181f5): The same Astro app deployed with --release-command node migrate.cjs; /migrated reported the migration marker. (expires 2027-03-19T01:42:25Z)
EXECUTION
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.
NEXT ACTIONS
Typed next actions
- Browse the catalog index (
GET /v1/catalogon the api origin; authentication not required, approval not required) - Search published recipes by intent, stack and constraints (
POST /v1/catalog/searchon the api origin; authentication not required, approval not required) - Prepare a side-effect-free deployment plan for an authorized project (
POST /v1/catalog/planon the api origin; authentication required, approval not required) - Read the existing agent authentication setup (
GET /mcp/setupon the api origin; authentication not required, approval not required) - Browse Astro (
GET /v1/catalog/nodes/stack%3Aframework-astroon the api origin; authentication not required, approval not required) - Browse Configure deployment (
GET /v1/catalog/nodes/intent%3Aconfigure-deploymenton the api origin; authentication not required, approval not required) - Browse Transactional workflows (
GET /v1/catalog/nodes/pattern%3Atransactional-workflowson 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.