Deployment Overview

Ultimo compiles to a single static binary — no runtime, no interpreter, no node_modules. This makes deployment straightforward on any platform that runs Linux containers or bare-metal binaries.

Build for release

cargo build --release

The optimized binary lands at target/release/<your-app> (typically 10–15 MB). Copy it anywhere and run it — zero dependencies beyond libc.

Guides

Production checklist

Before going live:

• Health check endpoint — add a GET /health route returning 200:

app.get("/health", |ctx: Context| async move {
    ctx.response().text("ok")
});

• Environment variables — don't hardcode secrets; use env vars or a secret manager

let db_url = std::env::var("DATABASE_URL")
    .expect("DATABASE_URL must be set");

• Logging — set RUST_LOG=info (or RUST_LOG=ultimo=info,my_app=debug)

• HTTPS — terminate TLS at the load balancer/reverse proxy (Caddy, nginx, cloud LB) — Ultimo serves HTTP, your infra adds the S

• Security headers — enable the built-in middleware:

app.use_middleware(ultimo::middleware::builtin::security_headers());

• Trust proxy — if behind a load balancer, enable so client_ip() reads X-Forwarded-For:

app.trust_proxy(true);

• IP filtering — restrict access if needed:

use ultimo::middleware::builtin::IpFilter;
app.use_middleware(IpFilter::allow(&["10.0.0.0/8"]).build());

• Graceful shutdown — Ultimo handles SIGTERM automatically; HTTP connections drain, WebSocket clients get close frames via broadcast_all()

• Resource limits — Ultimo binaries are lean; 64–128 MB RAM handles most workloads; set container limits accordingly

Environment variables

Ultimo apps typically read configuration from environment variables. Here's a common pattern:

use std::env;
 
let port: u16 = env::var("PORT")
    .unwrap_or_else(|_| "3000".to_string())
    .parse()
    .expect("PORT must be a number");
 
let host = env::var("HOST").unwrap_or_else(|_| "0.0.0.0".to_string());