Indium is a JavaScript development environment for Emacs.

Indium is Free Software, licensed under the GPL v3.0. You can follow its development on GitHub.

Indium connects to a browser tab or nodejs process and provides several features for JavaScript development, including:

  • a REPL (with auto completion) & object inspection;
  • an inspector, with history and navigation;
  • a scratch buffer (M-x indium-scratch);
  • JavaScript evaluation in JS buffers with indium-interaction-mode;
  • a stepping Debugger, similar to edebug, or cider.

This documentation can be read online at

It is also available in Info format and can be consulted from within Emacs with C-h i m indium RET.

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