Epupp: Live Tamper your Web

Tracking since Apr 1, 2026.

Changelog

• May 8, 2026
  description

  Epupp lets you tamper with web pages, live and/or with userscripts. It has two modes of operation:
  
  1. Live REPL connection from your editor to the web page, letting you inspect and modify the page on the fly, with or without the assistance of an AI agent.
  2. Userscripts: Tampermonkey style. Saved scripts that you can run, automatically or manually, on pages you visit.
  
  The two form a powerful pair. The live REPL connection, while happily supporting one-off changes or data extractions, is also a very efficient and fun means to interactively develop userscripts.

  Epupp lets you tamper with web pages, It has two modes of operation:
  
  1. Live REPL connection from your editor to the web page, letting you inspect and modify the page on the fly, with or without the assistance of an AI agent.
  2. Userscripts: Tampermonkey style. Saved scripts that you can run, automatically or manually, on pages you visit.
  
  The two form a powerful pair. The live REPL connection, while happily supporting one-off changes or data extractions, is also a very efficient and fun means to interactively develop userscripts.

Permissions & access

Permissions

scriptingactiveTabstoragewebNavigationalarms

Host access

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Screenshots

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