Releases

Every tagged build of os8088, newest first, with the same notes that go on the GitHub releases page. Each one is four raw floppy images built from a single commit, booted in an emulator before it was published.

Builds before the first tag are not listed: the project was published as images on the download page without a release behind them. The download page always serves the newest release, with checksums.

v1.0.20260728 latest

v1.0.20260728

Released 2026-07-28 from 698b5878c · on GitHub

The first tagged release. Optional double buffering, a graphical boot splash, 640KB boot targets, and the Note Pad moved out of the kernel onto the software floppy.

  • Optional double buffering #22
    Switchable at runtime from the Control Panel's new Display page, and off by default on every machine -- a 256K machine draws straight to video memory as before and can never leave that path. At 500K or more of conventional memory the kernel allows a four-plane back buffer at segment 0x4000, flushed one dirty rectangle at a time when the drawing lock drops. While everything on screen is black or white all four planes hold identical bytes, so the flush writes one plane and lets the Map Mask register fan it out; the transient XOR overlays, drag outlines and menu highlights, bypass the buffer entirely.
  • A graphical boot splash #21
    A spinning 8088 over a progress bar, drawn while the kernel loads.
  • 640KB boot targets #20
    make run-640 for QEMU and make xt-640 for 86Box, so the system can be exercised on a maxed-out period machine as well as a 256K one.
  • Repository housekeeping
    A CONTRIBUTING guide (#19), SECURITY.md (#18), a CODEOWNERS file (#17) and a tracked gitleaks pre-commit hook (#16).

Note Pad is no longer on the File menu. It left the kernel and became the NOTEPAD package on the software floppy: open File > Disk and double-click it. The File menu is now Clock, Bounce, Disk and Close Window.

Kernel image
16,281 bytes
Image + .bss
39,871 of 40,960 (1,089 free)
Source
12,848 lines of assembly across 20 kernel modules
Files in os8088 v1.0.20260728
FileWhat it isSize
os8088.imgBoot disk, 1.44MB geometry: 80 cylinders, 2 heads, 18 sectors per track. For QEMU.1,474,560 bytes
os8088-360.imgBoot disk, 360KB geometry: 40 cylinders, 2 heads, 9 sectors per track. For 86Box and real XT hardware.368,640 bytes
apps.imgSoftware disk, 1.44MB: an os88fs volume holding MINES, HELLO and NOTEPAD. Not bootable.1,474,560 bytes
apps360.imgSoftware disk, 360KB. The same three packages, same filesystem, different geometry.368,640 bytes

The download page serves these same four images with their SHA-256 checksums: os8088.com/download.

What a release is here

A release is a tag on the source repository plus the four images that tag builds: a boot disk in 1.44MB and 360KB geometries, and a software disk carrying the loadable packages in the same two geometries. Nothing is compiled on the way in -- the images published are byte-for-byte the ones the build produced, which is what the checksums on the download page are for.

The kernel size quoted with each release is the assembled kernel.bin. The second figure is that image plus every buffer the kernel statically reserves, which is the number that has to stay under 0xA000 -- the offset where loaded programs begin. A release that ran out of that headroom would not build at all.