Dev tools · alternatives · 2026
24 alternatives to I built an open-source kernel for Texas Instruments calculators
You know that old TI calculator you used in high school, then put in a box and forgot about? Have you ever wished you had an operating system for your calculator with preemptive multitasking, dynamic memory management, a tree filesystem conforming to the FHS, and all the comforts of Unix? Well, good news: that's totally a thing that exists. I've been working on my kernel for about three and a half years now and I'm looking for new contributors to help out. It's written entirely in z80 assembly, and it's both challenging and fun to work on. There's an IRC channel for contributors or people…
An open-source kernel designed for Texas Instruments calculators, written entirely in z80 assembly. It provides preemptive multitasking, dynamic memory management, and a Unix-like filesystem for vintage calculators.… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. I built an open-source kernel for Texas Instruments calculators launched in 2014; newer entries below may have overtaken it.
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Hi there! I've been on-and-off working on TacOS for a few months, which follows some UNIX-derived concepts (exec/fork, unix-style VFS, etc) and is now able to run a port of Doom, with a fairly small amount of modifications, using my from-scratch libc. The performance is actually decent compared to what I expected. Very interested to hear your thoughts. Thank you!
2025 · github.com · its alternatives →
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I launched NumPad v1 on here a few years ago, and back then it wasn't much more than a thin CodeMirror wrapper around the calculator engine I'd written. Now I've rewritten it as a PWA that supports multiple documents, persists them to IndexedDB, and has a syncing service for paying customers. Syncing is handled by Automerge[1] under the hood, which should make it relatively easy to get document sharing working too. [1] https://automerge.org/
2022 · numpad.io · its alternatives →
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🌐 The Internet Computer! Free, Open-Source, and Self-Hostable. - HeyPuter/puter
2024 · github.com · its alternatives →
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Hi HN, I’m Dvir, a young developer. Last year, I got rejected after a job interview because I lacked some CPU knowledge. After that, I decided to deepen my understanding in the low level world and learn how things work under the hood. I decided to try and create an OS in C and ASM as a way to broaden my knowledge in this area. This took me on the most interesting ride, where I’ve learned about OS theory and low level programming on a whole new level. I’ve spent hours upon hours, blood and tears, reading different OS theory blogs, learning low level concepts, debugging, testing and working on…
Oct 2025 · github.com · its alternatives →
- 6IM
https://github.com/siraben/ti84-forth Hi HN! For the past year I've been getting into programming in Z80 assembly (especially for the TI-84+). More recently I've been learning about the Forth programming language and after a lot of searching online (in vain) for a Forth interpreter for the TI-84, I decided to write one myself. It's been fun demoing this to others, because it's a very unexpected use of a calculator. It's my largest project to date, and I'm interested to know what the HN community thinks, please feel free to critique my code! -- Ben
2018 · its alternatives →
- 7KA
2016 · knightos.org · its alternatives →
- 8IM
https://github.com/siraben/zkeme80 As a successor to my previous project[1], a Forth interpreter that runs under the TI operating system, I decided to go all the way and write my own assembler and OS. This is a project I've been working on for just over a month, but there's still a long way to go. The idea is to have a kernel + the Forth interpreter and compiler, then users can modify how their operating system works through the Forth files. My Forth implementation is mostly ANS-standard conforming, so most code should work right out of the box without any problem. See…
2019 · its alternatives →
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I pretty much always have a kernel project going on, and have been that way for decades. Over the past couple of years, that's been Anos, which has gotten further along than any of my previous hobby kernels, supporting IPC, multitasking, SMP (x86-64 only right now) and running on real hardware. LLMs (mostly Claude Code) have been used during development, but I learned early on that it's not _great_ at code at this level, so I've restricted its use to mostly documentation and tests. There's _a little_ AI code in the user space, but I have a strict "no AI code" rule in the kernel itself. I…
Apr 2026 · github.com · its alternatives →
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The core question: how did HP's scientific calculators actually work at the gate level? That rabbit hole led to building one from scratch. The architectural decision everything else follows from: a decimal calculator should store numbers as BCD — one decimal digit per 4-bit nibble. A standard byte-oriented CPU (Z80, 6502) fights that layout constantly. So I designed a small custom CPU in Verilog where 4 bits is the natural data width and memory is nibble addressable. What the project covers: - Custom CPU: Harvard architecture, 12-bit ISA, 8-state execution FSM, hardware stack guard with a…
May 2026 · github.com · its alternatives →
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This project contains no code from Linux, BSD, Minix, or any other OS. Everything up until this point is written entirely from scratch, including a pure microkernel (that only implements multiprocessor priority scheduling, memory management, and interprocess communication), a work-in-progress implementation of the standard C library, and a variety of servers that provide drivers and other essential OS functionality. At the time of writing this post, the servers provide drivers for the keyboard, NVMe SSDs (that works on real hardware), a Unix-like virtual file system (with a single root…
2024 · github.com · its alternatives →
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This is a personal project I've been working on and off for the past few years. It's a set of tools that have allowed me to prototype quickly small (and increasingly bigger) kernels, and create userspace programs to interact with them. Supports riscv64, amd64 and i386. The intel port has been tested and used on real hardware, from big dual-socket Xeon machines to an old X220. It is all C, I have plan to make rust bindings for the kernel library. But again, they're plans at this stage. Porting to new architectures is relatively simple, a basic port to riscv took me a couple of weeks of…
2024 · github.com · its alternatives →
- 13AD
A new calculator software cannot really bring attention (https://chachatelier.fr/chalk/) However, I wrote a full article explaining why I had to build something "new" that does not behave like usual desktop calculator softwares : TL;DR All "small" calculator softwares I know share the same design flaws. And the GUI is not the only stumbling block in their poor efficiency. Handling correctly numerical approximations - expected or not - is crucial to trust the results. It is usually not done in lightweight tools. It should. So I prove that if I could do it, OS manufacturers…
2022 · its alternatives →
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A multitasking monolithic Kernel based x86 targeting Operating System written in C# from scratch aiming for high-level implementation of drivers in managed environment. - amaneureka/AtomOS
2017 · github.com · its alternatives →
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BareMetal for the private/public cloud. Contribute to ReturnInfinity/BareMetal-Cloud development by creating an account on GitHub.
Jan 2026 · github.com · its alternatives →
- 16IB
We wanted to do something very challenging to prove to ourselves that we can do anything we put our mind to. The reasoning for why we chose to build a toy TPU specifically is fairly simple: - Building a chip for ML workloads seemed cool - There was no well-documented open source repo for an ML accelerator that performed both inference and training None of us have real professional experience in hardware design, which, in a way, made the TPU even more appealing since we weren't able to estimate exactly how difficult it would be. As we worked on the initial stages of this project, we…
2025 · tinytpu.com · its alternatives →
- 17GI
Hi all! I'm going into my freshman year, and figured that the best way to prepare for the intro to programming Racket course would be to implement my own garbage-collected, dynamically typed, functional programming language in C ;) Anyways... here's the repo: https://github.com/liam-ilan/crumb I started learning C over the summer, so I still have a whole lot to learn... Any feedback would be greatly appreciated! :D
2023 · its alternatives →
- 18MP
I have been working on this game somewhat sparsely for the past three years or so. However, it is still in a very early stage, and there is a lot of work to do. One of my friends encouraged me to post about it here, since he felt people might find interesting how I don’t use any libraries for it. The game can be played on a browser by virtue of WebAssembly. There are native ports using either MiniFB or SDL2, but you have to build those yourself. I decided to write the game in C because I feel like it is a simple language that a lot of people can understand well enough, and I didn’t think I…
2023 · zamfofex.neocities.org · its alternatives →
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A fast, rootless sandbox and virtual resource runtime for any workload, including untrusted and AI-generated code. Daemonless: a real, kernel-enforced container in ~3.5 ms from an OCI image, out of one static binary - getkern/kern
Aug 2026 · github.com · its alternatives →
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I've been working on this for ~3 months now, with pretty slow progress to be honest. So far I've got an ATA PIO mode hard disk driver, a FAT32 file system, a real time clock driver, and of course the essentials (interrupts, keyboard, pixel graphics). Kernel panics also cause a blue screen of death xD. It uses a bitmap physical memory allocator, and I'm fixing some issues with paging at the moment as a work towards running userspace applications. I'd be interested to see your thoughts on it :D
2024 · github.com · its alternatives →
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Everything that would be here is in the README. I hope this gets big, it has tons of potential.
2013 · github.com · its alternatives →
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I work on R00M 101, a Reddit-based OSINT profiler. While building it, I realized most open-source intelligence (OSINT) tools are scattered across GitHub, outdated blog posts, or random Discords. So I put together a public-facing directory of 100+ OSINT tools used by analysts, journalists, and security folks, free, filterable, and categorized by risk, platform, and use case. The idea was to make something useful and no-friction. Built with static HTML + SQL backend + a lot of caffeine. Would love feedback on how to improve the UX or tool curation. If anyone wants to contribute tools or help…
2025 · r00m101.com · its alternatives →
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I've been tired with the current options on the market for awhile and decided to do something about it after the running into the disaster that is MLOps at my last two startups and having to manage a multiple operation platforms both for my fellow ML engineers, the general application CI/CD and orchestration layers while simultaneously building the application itself. Its still extremely early for the product but its functioning and is well on its way. I'd love feedback on the approach and peoples thoughts on the problem space. Personally my irritations have been in the poor tooling,…
2025 · egdaemon.com · its alternatives →
- 24AO
We're two college students building an XR(AR/VR) native Operating System with a custom kernel. We're also Open Source so feel free to check our GitHub Repository- https://github.com/manaskamal/XenevaOS . The journey hasn't exactly been easy, we've been criticized by a lot saying that whatever we're doing is impractical and that we're too ambitious. Regardless, we've been committed to reach our goal. Here to answer all questions and doubts. Answering one question beforehand because we know someone is going to ask it - Q: Why use your own kernel/ Why don't you use…
2025 · getxeneva.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →