# Ace Editor

Ace (Ajax.org Cloud9 Editor)

Repository: https://github.com/ajaxorg/ace
Canonical: https://ross.abutalabs.com/products/ace
Homepage: https://ace.c9.io
Language: JavaScript
License: NOASSERTION
License Family: other
Last push: 2026-08-13T14:19:45+00:00
Link (homepage): https://ace.c9.io

## Health v2 (maintenance only)
Score: 97/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 97, release rhythm 96, longevity 100
- inputs: {"age_days": 5789, "days_push": 20, "days_rel": 26, "gap_med": 14, "n_releases_24m": 24}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 27143, forks 5262 (observed 2026-08-28T04:11:47.429623+00:00)

## What it is
Ace is a standalone, embeddable code editor written in JavaScript for the browser, originally developed as the primary editor for Cloud9 IDE. It offers native-editor-level performance and features such as syntax highlighting for 120+ languages, 20+ themes, code folding, multiple cursors, and customizable keybindings including Vim and Emacs modes.

## Use cases
- embed a code editor in a web page
- replace a textarea with a syntax-highlighted editor
- build an online IDE or playground
- add syntax highlighting for 120+ languages to a web app
- support vim and emacs keybindings in a browser editor
- edit very large files in the browser
- add a live syntax checker to a web editor

## When to choose
- you need a battle-tested, high-performance browser code editor
- you want broad language and theme support out of the box
- you need to handle huge documents (millions of lines) in the browser
- you want vim/emacs keybinding support or TextMate grammar import

## When to avoid
- you need a full IDE with built-in project management and debugging
- you want a lightweight plain textarea with minimal footprint
- you need a native desktop editor rather than a web-embedded one
- you prefer a more modern editor like Monaco or CodeMirror for new projects

## Facets
- artifact type: library
- maturity: stable
- function: editor, ui-components, frontend-framework
- domain: web-development, frontend, developer-tools, text-editors
- platform: browser, cross-platform
- tags: code-editor, syntax-highlighting, embeddable, javascript, browser-based-editor, vim-mode, emacs-mode, code-folding, multiple-cursors, nodejs

## Member repositories
- ajaxorg/ace (main) score 97
- ajaxorg/ace-builds (mirror) score 59

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:47.429623+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:54:35.029931+00:00, confidence not recorded.
  - readme: https://github.com/ajaxorg/ace (fetched 2026-08-28T04:11:47.429623+00:00, sha 2edcb90a79b8)
  - homepage: https://ace.c9.io (fetched 2026-08-29T07:52:27.387869+00:00, sha 45d57865a915)
  - registry_npm: https://registry.npmjs.org/ace-builds (fetched 2026-08-29T07:52:27.391473+00:00, sha f087958f632f)
- Data as of 2026-08-30T08:39:29.467469+00:00.