#+TITLE: CLOSOS: Multiple Simultaneous Environments
#+ID: closos-multiple-environments
#+DATE: 2026-03-22
#+FILETAGS: :architecture:lisp:os:closos:security:

* Concept
CLOSOS supports multiple simultaneous global environments, where an environment is a mapping from names to objects (functions, classes, packages).

* Key Principles
- **Isolation by Scope:** Each user or process can operate in a private environment. Redefining a system function (like `print-object`) in one environment does not affect other users.
- **Dynamic Adaptability:** Facilitates safe experimentation with new features without risking system-wide corruption.
- **Late Binding:** References are resolved against the current environment at compile/load time, enabling live updates and hot-reloading.

* Source
:PROPERTIES:
:ID:       9c69a9ab-1c96-490e-9a8e-fbeafacba30e
:END:
- [[attachment:strandh-lispos.pdf][Robert Strandh, "CLOSOS: Specification of a Lisp operating system" (2013)]]