Deployment

Nexlm runs in two shapes from the same code:

Shape	Entry	Realtime	Background jobs	Best for
Vercel (serverless)	server/api/index.js	Polling fallback	On traffic + cron	Current production setup
Long-running server (Render, Railway, VPS)	server/src/index.js	Socket.io	Interval scheduler	Instant updates at scale

Vercel (current setup)

Two Vercel projects are connected to the Nexlm/nexlm GitHub repo and deploy on every push to main.

Project	Root Directory	Framework preset	Production URL
nexlm-server	server	Other	https://nexlm-server.vercel.app
nexlm-client	client	Vite	https://nexlm-client.vercel.app

1. Create a database

Create a PostgreSQL database — for example Neon from Vercel → Storage → Marketplace — and copy its connection string (use the pooled URL with ?sslmode=require).

2. Server environment variables

In nexlm-server → Settings → Environment Variables:

Variable	Value
DATABASE_URL	Your Postgres connection string
JWT_SECRET	48+ random bytes, hex
ENCRYPTION_KEY	32 random bytes, hex (64 chars) — back this up
PLATFORM_SECRET_KEY	A Stellar secret seed (S…)
CRON_SECRET	Random string (16+ chars)
CLIENT_URL	https://nexlm-client.vercel.app
PUBLIC_API_URL	https://nexlm-server.vercel.app
STELLAR_NETWORK	testnet
HORIZON_URL	https://horizon-testnet.stellar.org
CLOUDINARY_URL	Required for chat image uploads on Vercel
REQUIRE_KYC	Optional — false lets testers trade without KYC review

Generate secrets locally:

node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"   # ENCRYPTION_KEY
node -e "console.log(require('crypto').randomBytes(48).toString('hex'))"   # JWT_SECRET
node -e "import('@stellar/stellar-sdk').then(s => console.log(s.Keypair.random().secret()))"  # PLATFORM_SECRET_KEY (run in server/)

Redeploy after saving. The build runs npm run vercel-build, which generates the Prisma client and applies migrations whenever DATABASE_URL is set.

Missing variables

If anything is missing, every API request returns 500 SERVER_NOT_CONFIGURED with a details list of the variables to add — instead of Vercel's opaque FUNCTION_INVOCATION_FAILED.

3. Client environment variable

In nexlm-client → Settings → Environment Variables, set VITE_API_URL=https://nexlm-server.vercel.app and redeploy. (Production builds default to that URL if it's unset.)

4. Create an admin

Run the seed script locally against the production database:

cd server
DATABASE_URL="<production url>" ENCRYPTION_KEY=<same key> JWT_SECRET=<any> PLATFORM_SECRET_KEY=<same seed> \
ADMIN_EMAIL=ops@example.com ADMIN_PASSWORD='a-long-password-1' npm run db:seed

5. Verify

curl https://nexlm-server.vercel.app/health
# {"status":"ok","network":"testnet","runtime":"serverless","realtime":false,...}

How serverless mode works

• API — vercel.json rewrites every path to api/index.js, which boots the same Express app.
• Realtime — Socket.io isn't available on serverless functions. The client detects the failed connection and polls: the trade room and chat every 4 s, trade lists every 8 s, the market every 10 s.
• Jobs — order expiry, auto-refunds and reconciliation run at most every 15 s per instance whenever API traffic arrives. Viewing an overdue trade also settles it immediately. A daily Vercel Cron calls /api/cron/tick as a safety net; for minute-level coverage without traffic, point an external scheduler at the same endpoint with Authorization: Bearer $CRON_SECRET.
• Uploads — serverless disks are temporary, so uploads require CLOUDINARY_URL.
• Email and Friendbot — registration waits (up to 8 s) for wallet funding and the verification email so the function isn't frozen mid-request.

Long-running server (Render)

The repository also includes render.yaml for a single always-on API with Socket.io and the interval scheduler:

Setting	Value
Build	npm ci && npm run db:generate -w server
Pre-deploy	npm run db:deploy -w server
Start	npm start -w server
Health check	/health

Set the same secrets as above, then point the client's VITE_API_URL at the Render URL.

Going to mainnet

1. Set STELLAR_NETWORK=public and HORIZON_URL=https://horizon.stellar.org.
2. Use a new PLATFORM_SECRET_KEY generated offline and stored in a secrets manager.
3. Configure Smile ID production credentials (SMILE_ENV=production).
4. Configure Cloudinary and SMTP.
5. Review the security model and rate limits.
6. Run the smoke test against a staging testnet deployment before every release.

Wallets are network-specific

Testnet user wallets don't exist on mainnet. Launch mainnet with a fresh database.