lem-project/lem

Health v2 · maintenance only

Adoption not part of the score

3032 stars · 255 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

Lem is a general-purpose text editor and IDE written in and extensible with Common Lisp, offering Emacs/Vim-style keyboard workflows, built-in LSP support for many languages, and a full Common Lisp REPL and debugger. It runs as a terminal (ncurses) application or GUI (SDL2/webview) and can be extended live while running.

Use cases

• edit code with an Emacs-like keyboard-driven editor
• develop Common Lisp with a REPL and interactive debugger
• use LSP-based code intelligence across many languages
• extend an editor live in Common Lisp
• run a lightweight terminal IDE over ssh
• use a GUI editor with mouse support and color themes

When to choose

• you want an Emacs-like editor extensible in Common Lisp
• you do Common Lisp development and want an integrated REPL and debugger
• you need a fast terminal editor with LSP support
• you want one editor that works in terminal, ncurses, SDL2, and webview modes

When to avoid

• you need a large plugin ecosystem like VS Code's marketplace
• you prefer mouse-first GUI IDEs like JetBrains products
• you don't want to learn Lisp for customization
• you need mobile or web-based editing

Facets

application · maturity active

editor developer-tools gui cli text-editors developer-tools programming-languages windows cross-platform cli common-lisp lsp emacs-alternative extensible-editor repl ncurses sdl2 webview paredit lisp-ide linux macos desktop

Member repositories

For agents

markdown · JSON · MCP: product_card(name="lem-project/lem")