Apply Database Schema Changes for React Router

Apply database schema changes for a React Router app on Ample with a release command. node migrate.cjs runs against the injected DATABASE_URL before the new release goes live, and the release fails instead of activating if the migration fails.

Summary

• Framework operation: Framework
• Workload: Apply database schema changes
• Release Status: Published
• Support Status: Verified
• Execution Status: Ready

Prerequisites

• 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

Resource Requirements

• Compute: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
• Postgres: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

Workflow Steps

1. Write an idempotent migration: Create tables and markers with IF NOT EXISTS or a migration framework so a re-run is safe.

2. Deploy with the release command: Ample runs the command before activation; a non-zero exit fails the release.

   Command: ample deploy . --name --public --release-command "node migrate.cjs"

3. Verify the marker through the app: Serve a route (/migrated) that reads something only the migration creates.

4. 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.

   Command: ample logs --kind build

Success Checks

• Migration marker is readable via HTTP GET at the path /migrated, expecting migrated=release-ok.

Limitations

• Verified on the node-22 template at s-1vcpu-1gb; other templates and sizes are not verified by this recipe.
• Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.

Cost Estimate

• Monthly Amount: $10.00
• Currency: USD
• Breakdown:
  • App server: s-1vcpu-1gb - $5.00
  • Managed PostgreSQL database: s-1vcpu-1gb - $5.00

Examples

• React Router release-command canary: node migrate.cjs runs before activation against the auto-provisioned managed database.