Език: English
Free software lets you change the programs you use. Coding agents make it cheap to write the tool you want. I built Xi, an open-source terminal code editor in TypeScript on OpenTUI, alone with AI coding agents in about three to four weeks.
Xi combines Vim's editing model with Helix-style multi-cursor selections. Forking Neovim or Helix would have meant undoing their core decisions.
Before an agent implements a command, it adds a test. The test runs the same keys in Xi and a pinned Neovim or Helix and compares the results. One test caught Xi putting the cursor on the wrong line after O and Escape. The build fails on forbidden dependencies between modules. It also fails if keystroke overhead exceeds Neovim's by more than 3 ms at the 95th percentile.
Xi is young and has few users. The tests only cover what Neovim and Helix do. I still review design decisions myself.
I will end with how to decide between building a new tool and forking or contributing.
I'll explain why a new editor cost less than a fork. Then I'll show how I check each agent change against Neovim and Helix. I'll also cover how the build enforces module boundaries and speed, and where this approach still falls short. The code is on GitHub at github.com/OlegHQ/xi.