Deployment

Rex produces a single binary and a build output directory. Deploy it anywhere you can run a container or a Linux binary.

Docker

Rex includes a Dockerfile in every project. Build and run locally:

docker build -t my-app .
docker run -p 3000:3000 my-app

Example Dockerfile

FROM ghcr.io/limlabs/rex:latest AS builder
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
RUN rex build

FROM ghcr.io/limlabs/rex:latest
WORKDIR /app
COPY --from=builder /app/.rex .rex
COPY --from=builder /app/public public
CMD ["rex", "start"]

Docker Compose

version: "3.8"
services:
  web:
    build: .
    ports:
      - "3000:3000"
    environment:
      - PORT=3000

Cloud platforms

Rex works with any platform that supports Docker containers.

Railway

Deploy directly from a GitHub repo — Railway auto-detects the Dockerfile:

1. Connect your repo on Railway
2. Railway builds the Docker image and deploys
3. Set the PORT environment variable if needed (Railway provides it automatically)

Fly.io

fly launch
fly deploy

Fly detects the Dockerfile. Add a fly.toml to configure regions and scaling:

[http_service]
  internal_port = 3000
  force_https = true

AWS App Runner

1. Push your image to ECR
2. Create an App Runner service pointing to the image
3. Set the port to 3000

Google Cloud Run

gcloud run deploy my-app \
  --source . \
  --port 3000 \
  --allow-unauthenticated

Cloud Run builds from the Dockerfile and deploys a serverless container.

Azure Container Apps

az containerapp up \
  --name my-app \
  --source . \
  --ingress external \
  --target-port 3000

DigitalOcean App Platform

1. Connect your GitHub repo
2. Select "Dockerfile" as the build method
3. Set the HTTP port to 3000

Production readiness

Before deploying to production, verify:

• Visual correctness — review every page and interactive element in a staging environment
• Functional testing — test forms, navigation, data fetching, and error states
• Security — audit dependencies, validate user input, configure HTTPS and security headers
• Performance — run load tests to understand throughput and latency under expected traffic
• Monitoring — set up logging, error tracking, and health checks
• Environment variables — ensure secrets are stored securely and not committed to source control