An editor per student, all on one container

The CS instructor needs 40 students to have 40 working VS Code environments by Tuesday. Not laptops to install on. Not container quotas to argue with IT about. Working URLs.

She points each student at the same container URL with ?id= and their student number. Student 17 gets port 7017, data directory /data/instances/17/, their own extensions, their own settings. Student 18 gets a completely separate world on the same machine.

The economics work because the substrate works. The forty instances share one container's filesystem, the kernel's page cache loads the editor binary once for all of them, and idle instances burn no CPU. Forty editors on one bare metal box cost slightly more than one editor, not forty times.

Forty students, one container URL, one rented box. The infrastructure stops being the lesson plan's enemy.