There's a particular kind of developer who looks at their tools and thinks: I could build that. Most of the time, this impulse gets filed under "interesting but impractical." Sometimes, someone actually does it.
A developer named Joshua Barretto built a text editor from scratch and now uses it as their daily driver. Not as an experiment. Not as a side project gathering dust. As the actual tool they reach for when writing code. The write-up is a fascinating look at what happens when theoretical knowledge meets practical necessity.
Why Build Your Own Editor?
The obvious question is: why? VS Code exists. Vim exists. Emacs has been around longer than most developers have been alive. The ecosystem is mature, the tools are free, and they work. Building a text editor from scratch is the definition of reinventing the wheel.
Barretto's motivation isn't about replacing existing tools for everyone. It's about understanding them deeply enough to build one yourself. There's a category of knowledge that only comes from implementation. You can read about rope data structures for text buffers, but you don't really understand the tradeoffs until you've implemented one and watched it fall over under real-world use.
The other driver is control. Modern text editors are remarkably complex. VS Code ships with a JavaScript runtime, extension marketplace, integrated terminal, debugger, and git client. That complexity enables powerful features but comes with weight. A custom editor strips away everything except what you actually need. The result is faster, lighter, and perfectly suited to your specific workflow.
The Technical Decisions
Building a text editor means confronting a series of surprisingly difficult problems. How do you represent text in memory efficiently? A naive approach - storing text as a string - breaks down the moment you need to insert characters in the middle of a large file. Every insertion requires shifting thousands of characters in memory.
Barretto's solution uses a rope data structure - essentially a binary tree where each leaf contains a string fragment. Insertions and deletions become tree operations rather than array shifts. It's more complex to implement but scales far better as file size grows. The tradeoff: more complexity, better performance at scale.
Then there's rendering. Text on screen seems simple until you consider syntax highlighting, line wrapping, Unicode handling, ligatures, and smooth scrolling. Each feature adds layers of complexity. A production editor needs to handle all of this without dropping frames. That's genuinely difficult.
The write-up goes into detail on these tradeoffs. Not abstractly, but with the specificity that comes from hitting real problems. Why certain rendering optimisations matter. Which features turned out harder than expected. Where simplicity won over feature completeness.
Daily Driving Custom Tools
The interesting part isn't building the editor. It's using it. That's where theory meets friction. Small bugs that seemed minor in testing become annoying when they interrupt your workflow fifty times a day. Missing features you never thought about suddenly matter when you need them.
Barretto's experience highlights how much invisible complexity exists in mature tools. Auto-save seems trivial until you implement it and realise you need file watching, conflict resolution, and backup strategies. Undo/redo looks simple until you consider cursor position restoration, grouped operations, and memory management.
Daily use also forces prioritisation. With limited development time, which features matter most? Syntax highlighting for your primary language might be essential. Support for fifty languages might not be. A plugin system might seem critical until you realise you never actually used plugins in your previous editor.
What This Means for Developers
Building your own text editor isn't practical for most developers. The opportunity cost is too high. But the exercise reveals something valuable: understanding your tools deeply changes how you use them. Knowing why a feature exists, what tradeoffs it required, which problems it solves - that knowledge makes you a better user of any tool.
There's also a broader point about software complexity. Modern development tools have accumulated decades of features. Some are essential. Many are legacy. A few are actively harmful to workflow. Building from scratch forces you to question which is which. The result might not be better than established tools, but the thinking process is valuable regardless.
For anyone considering a similar project, Barretto's write-up is worth reading in full. It's honest about the difficulties, clear about the tradeoffs, and specific about implementation details. The kind of technical writing that's rare and useful.
Most developers won't build their own text editor. But understanding what goes into one makes you better at using the editors that already exist. And for the few who do take on the challenge, there's something satisfying about working in a tool you built yourself. Even if nobody else ever uses it.