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Ironclad OS

People like that it is an open source, formally verified Unix-like kernel written in Ada, and that many UNIX programs reportedly run on it. Critics say it is not yet proven for real-time production use and that its verification claims are unclear.

Summarized from 16 comments.

People like that it is an open source, formally verified Unix-like kernel written in Ada, and that many UNIX programs reportedly run on it. Critics say it is not yet proven for real-time production use and that its verification claims are unclear.

recommend
12
criticize
4
months recommended
2 of 13

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The 13 most detailed of 16 comments. Each links to the original.

  1. I know only one OS working on that which is open source Ironclad OS

    Recommends · Oct 2026 · in “Several vulnerabilities have been discovered in the Linux kernel”

  2. A formally verified OS is a great step towards better security.

    Recommends · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  3. Great to see an open source kernel written in Ada.

    Recommends · Nov 2025 · in “There's No Rust on This Ironclad Kernel”

  4. They don’t prove anything important about the kernel clearly at all.

    Criticizes · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  5. I don't see any interesting specifications in the repo

    Criticizes · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  6. it seems to be little more than a mission statement

    Criticizes · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  7. I'm skeptical that this is actually production usable for the hard real-time use cases

    Mixed · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  8. fully posix-compliant, meaning that you can run a lot of UNIX programs on it already

    Recommends · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  9. My main concern is speed and the lack of capability based security.

    Mixed · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  10. it makes me happy to see it getting a bit more love

    Recommends · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  11. is not wanting to boot on my QEMU

    Mixed · Nov 2025 · in “Ironclad OS project popping out Unix-like kernel using Ada”

  12. I am huge fan of works like this

    Recommends · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

  13. Commercial support is not free, and the pricing for that is almost always something you have to ask for.

    Criticizes · Nov 2025 · in “Ironclad – formally verified, real-time capable, Unix-like OS kernel”

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