Mitchell Hashimoto's personal website.
Visit mitchellh.com → RSS feedOn Hacker News Jan 2014 – Oct 2026
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Since then, I've opened GitHub every single day. Every day, multiple times per day, for over 18 years. Over half my life. A handful of exceptions in there (I'd love to see the data), but I can't imagine more than a week per year.
Ghostty is now fiscally sponsored by Hack Club , a registered 501(c)(3) non-profit.
My experience adopting any meaningful tool is that I've necessarily gone through three phases: (1) a period of inefficiency (2) a period of adequacy, then finally (3) a period of workflow and life-altering discovery.
Over two years ago, in one of my first public talks about Ghostty , I shared my vision for libghostty : an embeddable library for any application to embed their own fully functional, modern, and fast terminal emulator. Libghostty is finally starting to take shape, and I'm excited to share more details about my plans…
My family is pledging another $400,000 1 to the Zig Software Foundation (ZSF). This brings our total pledged support for ZSF to $700,000, after our initial donation in 2024 .
SIMD has a reputation for being complex. I've met many very good software engineers who dismiss it as something too complex to learn or a niche optimization meant for only the highest-performance software, not useful in everyday programming.
A few months ago, users started reporting that Ghostty was consuming absurd amounts of memory, with one user reporting 37 GB after 10 days of uptime. Today, I'm happy to say the fix has been found and merged . This post is an overview of what caused the leak, a look at some of Ghostty's internals, and some brief…
As a relatively new member of adult society, and an absolute infant of the business world, I didn't think much about bank choice. I figured: you put money in, you take money out, they're all the same. I also figured a local branch of a global bank is just a fungible tentacle of the giant banking machine, so also…
The ZSF has posted their own announcement which clearly explains their mission and specifically what the money will be used for. Instead, I want to talk more broadly about why we've decided to support ZSF.
Andrew Kelley famously (or infamously, depending on your views) said "the compiler is too damn slow, that's why we have bugs." 1
We just completed rewriting the Ghostty GTK application fully embracing the GObject type system from Zig and also verifying with Valgrind every step of the way. The result is a more feature rich, stable, and maintainable Ghostty on Linux and BSD.
Whether it's building a new project from scratch, implementing a big feature, or beginning a large refactor, it can be difficult to stay motivated and complete large technical projects. A method that works really well for me is to continuously see real results and to order my work based on that.
You see a series of checkboxes checked. Schedules met. Requirements satisfied. Demos delivered. It's a good day. Good job, you, good job! A promotion is in sight.
"Prompt Engineering" emerged from the growth of language models to describe the process of applying prompting to effectively extract information from language models, typically for use in real-world applications.
I recently shipped a non-trivial Ghostty feature (unobtrusive macOS automatic updates) that was largely developed with AI.
I've had the experience of using GitHub as a maintainer for very large open source projects (1000+ contributors), as an engineer for very large closed source corporate projects, and everything smaller. Through those experiences up to today, GitHub pull requests is where I spend almost all of my time while on GitHub…
I wrote a specification for a new terminal escape sequence: OSC 7501, the Program Status Protocol . It lets any program tell the terminal what it's doing: idle, working, waiting on the user, finished, or failed, and why.
Building a native GUI for a cross-platform application is a decades old problem. Nowadays, most people just don't and fallback to using a non-native experience such as Electron instead.
I authored 1 the announcement post on the Superlogical homepage , which describes the problem statement and what we're building. 2 Read that to learn more. This post is more of a personal statement about what led to this, how it relates to my recent work, and what comes next.
For years, the primary bottleneck for virtual machine based development environments with Vagrant has been filesystem performance. CPU differences are minimal and barely noticeable, and RAM only becomes an issue when many virtual machines are active.
My writings about Ghostty, the terminal emulator I work on.