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Dev tools · alternatives · 2026

KA

KnightOS is an open-source operating system designed for calculators. The project provides an SDK for building packages, though it experienced a period when package hosting was unavailable. Recently, alternative… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. KnightOS – An open-source OS for calculators launched in 2016; newer entries below may have overtaken it.

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    KnightOS▲136

    An open-source OS for calculators

    2016 · its alternatives →

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    The operating system for smart frames. Runs on a Raspberry Pi or ESP32, renders on e-ink, HDMI and LCD displays. Standalone, self-hosted, or managed from FrameOS Cloud - everything renders on the device.

    2024 · frameos.net · its alternatives →

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    An application innovation platform delivering a comprehensive experience with tools to empower organizations to modernize and build new applications, accelerate AI adoption, and fuel growth.

    2013 · coreos.com · 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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    The open-source Hubspot alternative

    2022 · erxes.io · 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 →

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    An operating system written in JavaScript. Contribute to haileys/jsos development by creating an account on GitHub.

    2012 · github.com · its alternatives →

  8. 8IB

    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…

    2014 · its alternatives →

  9. 9KA
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    At Cajal (YC W26) we’re excited to share Talos (https://github.com/cajal-technologies/talos), an open source framework for formal verification of WebAssembly modules in Lean. AI is now writing tons of the code that gets pushed to production. As code generation gets cheaper, verification becomes the bottleneck. We believe in a future where every piece of software comes with a mathematical proof that it does what its author intended - in doing so, eliminating many classes of exploits. Talos is part of the foundation for that. Talos provides a Wasm interpreter optimized for…

    Jun 2026 · github.com · its alternatives →

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    The modern calculator for macOS/iOS

    2020 · euclid.pr1mer.tech · its alternatives →

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    Kalker is a calculator that supports user-defined variables, functions, ambiguous syntax, differentiation and integration. It runs on Windows, macOS, Linux, Android, and in web browsers (with WebAssembly).

    2021 · kalk.strct.net · its alternatives →

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    An open-source robotic process automation system 🚀

    2019 · orchestra.b12.io · its alternatives →

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    A smart notepad with a built in calculator

    2019 · soulver.app · 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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    Open source mobile OS focused on privacy and security.

    2019 · grapheneos.org · 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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    CasaOS▲98

    A simple, easy-to-use, elegant open-source home cloud system

    2021 · casaos.zimaspace.com · its alternatives →

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    The open-source engineering operations platform

    2022 · github.com · its alternatives →

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    A simple command-line calculator written in Go. Contribute to alfredxing/calc development by creating an account on GitHub.

    2015 · github.com · its alternatives →

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    Hi HN - DBOS CEO here with the co-founders of DBOS, Peter (KraftyOne) and Qian (qianli_cs). The company started as a research project of Stanford and MIT, and Peter and Qian were advised by Mike Stonebreaker, the creator of Postgres, and Matei Zaharia, the creator of Spark. They believe so strongly in reliable, serverless compute that they started a company (with Mike) to bring it to the world! Today we want to share our brand new Python library providing ultra-lightweight durable execution. https://github.com/dbos-inc/dbos-transact-py Durable execution means your program…

    2024 · github.com · its alternatives →

  24. 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 →