How did you deploy and launch four applications in the working environment?

To deploy and run four applications in a working environment, I usually use containerization with Docker and orchestration with Docker Compose or Kubernetes. This allows isolating each application and managing their lifecycle centrally.

Example with Docker Compose for four applications:

version: '3'
services:
  app1:
    build: ./app1
    ports:
      - "8001:8000"
  app2:
    build: ./app2
    ports:
      - "8002:8000"
  app3:
    build: ./app3
    ports:
      - "8003:8000"
  app4:
    build: ./app4
    ports:
      - "8004:8000"

Running all applications with one command:

docker-compose up -d

If the environment is more complex, I use CI/CD pipelines for automation of build, testing, and deployment. I can also apply Python virtual environments (venv) and system services (systemd) to manage applications on the server.