Detect
Deadlines, integrity checks and supervised services make failures visible instead of silent.
Bounded · fail-closed · observable
REIST-OS · Resilient x86 Research Operating System Resilience is a system property.
REIST-OS is a compact x86 research operating system. Its working i386 system detects faults, contains damage and validates bounded recovery; a separate x86_64 bootstrap now proves the migration foundations through generation-scoped FIFO scheduling.
- Ring-3 isolation
- Bounded recovery
- i386 fallback + x86_64 path
[boot] kernel CRC32 verified
[storage] AHCI controller ready
BOOT_OK
RESOURCE_QUARANTINED 0
media identity verified
undo journal recovered
storage fence released
RESOURCE_REINTEGRATED_RW 0
C:\>_
Engineering principles
Fail closed before side effects.
Every critical path is designed around explicit bounds, protected state and evidence-driven recovery.
Contain
Ring-3 domains, generation-scoped handles and output fences limit the authority of failed components.
Recover
Transactional storage and bounded restart paths restore a known state without blind retries.
Validate
Fresh reads, identity checks, CRCs and self-tests verify the result before capability is restored.
Reintegrate
Read/write access returns only after every required recovery gate has passed.
Diagnose
Build IDs, failure context and bounded panic records turn hardware tests into actionable evidence.
System architecture
Small layers. Explicit authority.
Ring 3Shell · compositor · audio and storage services · system toolsVersioned syscalls, bounded IPC and supervised generations
KernelSupervisor · scheduler · VFS · safety domainsProtected control objects and revocation
StorageMBR provisioning · FAT12 · REIST FAT32 · EXT2Transactional metadata, journal and fail-closed fencing
HardwareAHCI/SATA · ATA/IDE · USB/PS/2 · PCI · Ethernet · HDABounded polling, mediated resources and explicit device qualification
x86_64Higher-half paging · ELF64 · CPL3 · syscalls · PIT preemption · four-slot FIFOAccepted isolated bootstrap through R8.1k; not yet the production system
Storage lifecycle
Provision, maintain and recover without blind mutation.
The current Ring-3 toolset covers empty-disk setup, bounded administration and rescue execution while the kernel retains authority over every state transition.
Partition and format
fdisk creates aligned MBR partitions on empty disks. format provides verified REIST FAT32 quick format and a bounded full scan that blacklists defective data clusters.
Live maintenance
devctl, mount and umount expose explicit down/up and filesystem lifecycle operations with protected root resources, deadlines and media requalification.
Resident administration
Integrity-checked rescue tools remain executable after root-storage loss. System programs use a lowercase /bin, /sbin and /libexec/reist hierarchy, while the shell provides command history with cursor navigation.
Verified project status
Runs in VMs and on real BIOS hardware.
REIST boots through its own BIOS/MBR path, runs isolated userspace programs and supervised GUI, audio and storage components, provides an in-memory kernel log through dmesg, and has completed bounded SATA recovery on real hardware. The desktop starts only on an explicit shell command so boot diagnostics remain visible.
Research scope: REIST-OS is not certified and does not claim general fail-operational or safety-critical suitability.
- VerifiedQEMU AHCI/SATA guest pathBoot, filesystem I/O and Ring-3 recovery probe
- VerifiedLive disk provisioning in QEMUAligned MBR partition, REIST FAT32 quick/full format and mounted result
- VerifiedReal SATA hotplug recoveryQuarantine, journal recovery and read/write reintegration
- VerifiedVMware desktop and audio pathExplicit desktop start, system sounds and one-shot WAV playback
- VerifiedASUS USB keyboard and kernel logxHCI/USB boot input and paged
dmesgdiagnostics confirmed on hardware - ActiveStaged x86_64 migrationR8.1k proves ELF64 CPL3 execution, timer preemption and a four-generation FIFO; i386 remains the production fallback
AI transparency
Agent-assisted, human-directed.
REIST-OS is developed with agentic AI assistance to automate as much implementation, testing, documentation and repetitive verification as responsibly possible. This use is disclosed so the origin and review path of project changes remain clear.
AI does not develop REIST-OS without control.
- Work follows explicit architecture contracts, scoped tasks and acceptance gates.
- Generated changes are built, tested, documented and committed with traceable evidence.
- Architecture decisions, safety claims, release decisions and real-hardware validation remain under human direction and review.
- Automation increases coverage and speed; it does not replace engineering responsibility.
Captured from QEMU
The actual system, not a mock-up.
These are accepted captures from real REIST-OS guest runs, not mock-ups. They document the production i386 path; the newer x86_64 work is intentionally represented by test evidence rather than a synthetic desktop image.
SYSINFO identifies the current i386 Ring-3 system; x86_64 remains a separately gated bootstrap.
Build and run
One repository. Three targets.
The Windows build produces a raw BIOS disk, a floppy image and a ready-to-run VMware package.
PowerShell
.\scripts\build-windows.ps1 -Target real_hwOutput: build\reist-os.img
REIST-OS
Inspect the mechanisms, not just the claims.
The source, tests, architecture contracts and executable roadmap are available together.