Fly.io deployment

What gets deployed

Fly.io is used to run the API service (apps/api) as a container built from the monorepo. The deployment uses Turbo prune to keep the image lean while still including shared packages.

Files to know

• apps/api/fly.toml — Fly app configuration (region, port, health checks, scaling).
• apps/api/Dockerfile — multi-stage Bun build using turbo prune @plop/api --docker.
• apps/api/.dockerignore — trims the build context.

Prerequisites

• Install the Fly CLI (flyctl) and log in.
• Confirm you have all required API secrets (see env-and-secrets).

Configure the Fly app

Update apps/api/fly.toml before the first deploy:

• app — set this to your Fly app name.
• primary_region — pick the region closest to your database or users.
• min_machines_running / [[vm]] — adjust for your availability + budget.
• PORT / internal_port — keep this aligned with the API port (defaults to 3003).

Set required secrets

From the repo root, set the API environment variables on Fly. Replace the values below with your production secrets (for local dev, use the .env examples in env-and-secrets).

fly secrets set --config apps/api/fly.toml \
  APP_URL=https://app.plop.email \
  NEXT_PUBLIC_SUPABASE_URL=... \
  SUPABASE_SECRET_KEY=... \
  DATABASE_PRIMARY_URL=... \
  DATABASE_LHR_URL=... \
  DATABASE_SESSION_POOLER=... \
  UPSTASH_REDIS_REST_URL=... \
  UPSTASH_REDIS_REST_TOKEN=... \
  INBOX_ROOT_DOMAIN=in.plop.email \
  INBOX_WEBHOOK_SECRET=... \
  ALLOWED_API_ORIGINS=https://app.plop.email

Optional billing variables (only if Polar billing is enabled):

fly secrets set --config apps/api/fly.toml \
  POLAR_ACCESS_TOKEN=... \
  POLAR_ENVIRONMENT=production \
  POLAR_WEBHOOK_SECRET=... \
  POLAR_STARTER_MONTHLY_PRODUCT_ID=... \
  POLAR_STARTER_YEARLY_PRODUCT_ID=... \
  POLAR_PRO_MONTHLY_PRODUCT_ID=... \
  POLAR_PRO_YEARLY_PRODUCT_ID=... \
  POLAR_ENTERPRISE_MONTHLY_PRODUCT_ID=... \
  POLAR_ENTERPRISE_YEARLY_PRODUCT_ID=...

Deploy

Run the deploy from the repo root:

fly deploy --config apps/api/fly.toml

The Dockerfile sets NODE_ENV=production and runs the API with Bun.

Verify

fly status --config apps/api/fly.toml
fly logs --config apps/api/fly.toml
curl https://<your-app>.fly.dev/health

Scaling and regions

Common operations:

fly scale count 2 --config apps/api/fly.toml
fly scale memory 1024 --config apps/api/fly.toml
fly regions add lhr --config apps/api/fly.toml

If you add regions, ensure your read replica URLs (DATABASE_LHR_URL, DATABASE_SESSION_POOLER) are set appropriately.