Shannon

Mode Switching

Shannon has two modes — press Shift+Tab to toggle between them:

nu ↔ bash

Switching in Action

[nu] ~/project > ls | where size > 1mb
...
[nu] ~/project > <Shift+Tab>
[bash] ~/project > echo hello && echo world
hello
world
[bash] ~/project > <Shift+Tab>
[nu] ~/project >

The prompt updates immediately to show the active mode.

What Carries Over

When you switch modes, these are preserved:

  1. Environment variables — export FOO=bar in bash is visible as $env.FOO in nushell
  2. Working directory — cd /tmp in bash means you’re in /tmp when you switch to nushell

Environment variables are converted automatically between nushell’s typed values and bash strings using ENV_CONVERSIONS.

What Doesn’t Carry Over

Shell-internal data stays within its mode:

  • Nushell variables (let x = 5) don’t exist in bash
  • Bash local variables and aliases don’t exist in nushell
  • Only exported environment variables cross the boundary