Again, it's integrated in vs code and GitHub codespaces. If you open your project in vs code it detects the devcontainer config and automatically launches the container using docker, connects vs code remotely to code in the container, and pops open any terminals or tool executions in the container.

On GitHub codespaces it gives you a button on the website that is literally one click and get vs code in the browser connected to your dev container launched in their cloud--you don't even need vs code or anything installed and can code from a tablet for example.