What a BASIC‑Written Vi Looks Like

To celebrate Vi’s 50th anniversary, Lee Tusman built a Vi clone using Yabasic, an open‑source BASIC interpreter for Unix and Windows, writing only a few hundred lines of code.

“For a modern BASIC language it’s surprisingly fun to use,” Tusman said.

Tusman is not a professional programmer; his background is in art and he only began exploring BASIC in 2025, specifically the Yabasic interpreter.

Inspired by text‑based games such as Offpunk and a desire to try something unconventional, he wondered how difficult it would be to implement a very simple editor with the smallest possible set of Vim commands.

Using Yabasic, he first created a blank editing screen, then added basic commands. Within a short time the editor could open files, create new ones, and save changes. The implementation deliberately omits line‑wrap and limits lines to 80 characters, but the GitHub repository provides a runnable program that reproduces many of Vi’s historically obscure shortcuts.

“I’ve been using Neovim (formerly Vim) for years. I’ve never written a text editor before, but I thought trying to implement one might be fun.”

Tusman acknowledges that the current version lacks many features, such as line‑number display and a cross‑platform solution for screen‑scaling errors, and he may add them selectively in future forks.

He describes the clone as the best BASIC‑based Vi implementation he has found and notes that the code is in the public domain, inviting other BASIC enthusiasts to fork and extend it.