Deploy an app

This page packages a TypeScript server as a container image on elide.dev/elide.

Write the app

// server.ts
import { Hono } from "hono";

const app = new Hono();

app.use(async (c, next) => {
  await next();
  console.log(JSON.stringify({ method: c.req.method, path: c.req.path, status: c.res.status }));
});

app.get("/healthz", (c) => c.text("ok"));
app.get("/", (c) => c.json({ greeting: process.env.GREETING ?? "hello" }));

export default app;

// healthcheck.mjs
const res = await fetch("http://127.0.0.1:8080/healthz");
process.exit(res.ok ? 0 : 1);

{
  "name": "deploy-app",
  "type": "module",
  "dependencies": {
    "hono": "^4.7.0"
  }
}

Run elide install --ecosystems=npm once to write aube-lock.yaml.

Write the Dockerfile

FROM elide.dev/elide:1.6.0
WORKDIR /app
COPY package.json aube-lock.yaml ./
RUN elide install --ecosystems=npm
COPY . .
EXPOSE 8080
HEALTHCHECK --interval=10s --timeout=3s CMD ["elide", "healthcheck.mjs"]
CMD ["--allow-read=/app,/root/.cache/aube", "--allow-net=api.example.com", "serve", "--no-tui", "--host", "0.0.0.0", "--port", "8080", "server.ts"]

# .dockerignore
node_modules
.env

docker build -t my-app .
docker run -d --name my-app -p 8080:8080 -e GREETING=hi my-app
curl http://127.0.0.1:8080/

{"greeting":"hi"}

docker inspect --format '{{.State.Health.Status}}' my-app prints healthy once the first check passes. docker stop ends the server within a second, with exit code 143.

Pass environment variables

process.env holds the container’s variables; pass them with docker run -e NAME=value or Docker’s --env-file .env. This supplies configuration without copying the file into the image.

For local runs with Elide 1.6.2 or later, the launcher reads .env and .env.local automatically. Use --env-file to select other files or --no-env to disable loading. Elide does not set NODE_ENV. See Environment and properties for precedence and Environment variables for JavaScript access.

Restrict the server

Programs run unrestricted until a sandbox flag is given. Grant a server what it needs and nothing else:

Global flags go before the command (serve, run). --deny-net and --deny-run need the = form. Leaving the npm store out of --allow-read stops the server at startup:

Error: Filesystem read denied by policy: /app/node_modules/hono

A blocked outbound call names the flag:

fetch to '169.254.169.254:80' denied by --deny-net

Every flag: Sandbox and Limits.

Read logs

console.log writes to stdout and console.error to stderr; docker logs shows both:

{"method":"GET","path":"/healthz","status":200}
{"method":"GET","path":"/","status":200}

elide serve --no-tui prints no access log, and a handler that throws answers 500 without printing the error. Log requests and errors in the app, or export request spans, metrics, and errors with OpenTelemetry.

Deploy a JVM app

• Build a JVM image from elide.pkl with a ContainerImage artifact: JVM Containers.
• Compile a native executable: Native Image.