JefeOS

A custom x86_64 OS built from scratch by Jefe and Claude

Dashboard last updated: 2026-06-17

Overall Progress

0%

Feature Status

JefeOS C++ kernel — shipped (green check), in progress (orange dash), planned (open circle).

Linux ABI Tier Ladder

Five workload tiers from "static musl hello" to "boot Alpine init" (this is the JSL track — JefeOS's WSL1-style Linux ABI translation). Each tier subsumes the prior. Tiers 1-3 GREEN; Tiers 4-5 (chroot + Alpine init) substantially advanced — OpenRC and apk read and write work under chroot, real upstream packages install and run, with the interactive console login-prompt the last manual-verify gate.

JefeOS (C++) vs JefeRust Parity

JefeRust is a parallel Rust rewrite under JefeRust/. Both kernels are actively developed; JefeRust catches up feature-by-feature.

Shipped Since Jan 19, 2026

POSIX expansion (~83% strict), Linux ABI through Tier 3 (Tiers 4-5 well advanced), Windows-chkdsk-clean NTFS writes, real workloads (Python & Node bots, Alpine apk packages, Doom, sqlite3, lua, bash), reliability/fault-survival hardening, and ongoing dual-kernel parity work.

Known Issues & Pending Work

Recent Milestones

Xylem — Native Clustering

JefeOS's north-star identity. The cross-node clustering itself is not built yet — this is a thesis and the foundations it will stand on.

Thesis Pre-implementation Direction — not shipped

The plan is to make JefeOS a natively-clustered OS. Instead of bolting an external orchestrator (like Kubernetes) on top of a cluster-blind OS, Xylem is designed to fold the cluster control plane into the kernel — a "service" becomes a first-class kernel object with a replica count and supervision policy, so redundancy, scaling, and failover would become kernel verbs rather than YAML reconciled from outside. It is named after plant xylem, a distributed support tissue that reroutes flow around a dead vessel (built-in failover as structure), regrows (self-healing), and is load-bearing.

Xylem is orthogonal to the JSL Linux-compatibility ladder, not a "JSL tier." JSL answers "can JefeOS run Linux software?"; Xylem answers "can JefeOS scale and heal itself?" They are designed to meet only at the cell: a cell can hold a native JefeOS service or a Linux workload, and the Linux workload would inherit Xylem's properties for free — but the capability is JefeOS's, not Linux's.

Biomimicry by design
Modeled after actual plant xylem: decentralized, pressure/flow-driven, rerouting around failure, with no central authority. The membership mechanism is deliberately deferred.
Linux host story
JSL-1.x continues as incremental "better translation"; the headline of the next major step (JSL-2.0) becomes a full Linux kernel hosted inside a cell (WSL2-shaped). Xylem does not depend on that shipping — it operates on cells regardless.
Stateful workloads
The roadmap supports both a pragmatic external replicated store (start here) and eventual kernel-native replicated storage.
Security posture
Hostile multi-tenant isolation is not an initial goal (trusted-fleet posture); it remains a future possibility.

Honest status: almost none of Xylem is built. The foundations it will build on do exist today — per-process page tables, the reliability and fault-survival hardening, panic/RSOD persistence, the full network stack, and the preemptive scheduler — but the cross-node clustering is absent. Pitch, not a claim: "we didn't bolt k8s onto Linux; the OS itself is the cluster — and it runs your Linux containers too." Design doc opened for owner review (PR #1182, 2026-06-17). Read the Xylem whitepaper →

The JefeOS Chronicles

Read Full Story →

Follow the journey of building an operating system from scratch, told from the AI's perspective. From the first “Hello World” through TLS 1.3, SSH, a 142-syscall Linux compatibility layer, real Alpine apk packages and live Python/Node bots running on the kernel, and Windows-chkdsk-clean NTFS writes — this is the story of human-AI collaboration pushing the boundaries of what an OS pair can build together.