Robert Allan JamesandClaude Sonnet 5
986d042aa7
Fourth stage of the preemptive context-switching plan, and the biggest. LithosAnanke now genuinely, continuously preempts between Hera, Hermes, and Artemis -- timer-driven, running live for the entire remainder of every boot once the Tripod fleet registers, not a bounded probe. A real design fork was resolved before writing code: the naive approach (the timer ISR calling Stage 2's sk_vm_context_switch() directly) is broken -- Stage 0's trap frame lives on whatever stack was active at interrupt time, and jumping to a different stack via Stage 2's own independent swap mid-handler would abandon that trap frame unresumed, guaranteed corruption on the first tick. Chose the safer of two named options: the ISR only ever sets a flag and returns completely normally through its own full epilogue; the actual switch happens moments later, via Stage 2's already-proven mechanism, at a safe cooperative checkpoint on the mainline (execute_colon_word()'s per-word dispatch loop, checked on literally every word, not throttled to the existing 256-word heartbeat-tuning cadence) -- confirmed with the user that word-level granularity is fine-grained enough given the eventual Zynq FPGA target where a word is a mnemonic. New capsule_vm_switch_signal.c/.h: a purpose-built run-readiness signal, deliberately separate from capsule_vm_physics.c's execution-heat engine (that one's own header documents itself as never touched from interrupt context, by design). Slot table sized with headroom (8) rather than hardcoded to today's 3 participants, so extending participation later is another register() call, not a redesign -- per direct request to leave room for swapping the participant set. Simple linear accumulate-then- threshold for this first cut; a fancier law can replace it later without touching the mechanism around it. heartbeat_tick() gains its one deliberate, documented amendment to this file's own top-half/bottom-half discipline -- the first time this codebase reaches into VM-scheduling state from real ISR context. Registration happens only after all three VMs are fully born, right before the REPL starts -- no critical-section protection yet against being switched away mid-birth-setup. Known, flagged rough edge (not reconciled this pass): MSG-TICK's own idle-pump and this new mechanism can still independently move control between the same VMs; not observed to interact badly in verification, but not fully unified either. Verified interactively at the console on all 3 architectures with continuous background preemption running throughout -- amd64 computed `1 1 + .` -> 2, aarch64 computed `1 1 + dup DUP * . CR` -> 4, both correct, REPL fully responsive, zero fault indicators over sustained runtime. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_016UNhH1mhi52i6Qihh7ZV5S
LithosAnanke v2.0.1
UEFI-bootable FORTH microkernel. Boots from firmware, initialises memory and interrupts, then runs the StarForth VM as its sole userspace runtime. No libc. No OS. Just stone and necessity.
Lithos (foundation) + Ananke (necessity) — the kernel under StarshipOS.
Status — M7.1 (Capsule System · Multi-VM Fleet)
| Milestone | Status | |
|---|---|---|
| M0–M6 | UEFI boot · PMM · VMM · IDT · APIC · heap · framebuffer VT100 console (v1.5.1-FINAL) | ✅ Complete |
| M7 | StarForth VM integration + parity validation | ✅ Complete |
| M7.1 | Capsule birth protocol · Mama FORTH vocabulary · Tripod multi-VM fleet (Hermes/Artemis) · Word-level ACL (Phases 1–7) | 🔄 In Progress |
| M8 | REPL — keyboard input, interactive Forth | Planned |
| M9 | Block storage — AHCI driver | Planned |
POST at boot: parity hash verified across amd64/aarch64/riscv64 · Mama capsule dictionary: 453 words
What's live in M7.1
- Tripod — a named multi-VM fleet (Hera the Mama VM, Artemis, two Hermes instances) births, runs, and re-births independently, verified booting live pre-REPL on all three architectures.
- Hermes — a 17-block inter-VM messaging/channel layer between fleet members, with async delivery and channel negotiation.
- Artemis — a Block Allocation Map (BAM) storage subsystem with Q48.16
block-heat tracking and cooldown/reclamation (
ART-COOL/ART-REAP). - Word-level ACL — every dictionary entry carries a TTL/allow/mode/pin
access-control record. Strict, TTL, and pinned modes; two console layers
(emergency
ok>and superuserzuse)ok>). Phases 1–7 complete (C infrastructure, FORTH policy layer,zusebootstrap superuser, Isabelle proof stubs, kernel parity); Phase 8 (Ed25519 PKI / thumbdrive challenge-response) is the only item remaining. Measured overhead once active on every check: +0.0054%–+0.0088%, CV = 0.000%, across a 3×3 Latin-square DoE campaign (architecture × seed × 30 replicates) — three orders of magnitude below the measurement floor. - VM Fleet Attractor physics — the L8 Jacquard mode selector now has a real per-VM heat channel into fleet-wide tuning, replacing hardcoded compudynamics constants with a dynamically-inferred rate.
- Kconfig build configuration — every physics/heartbeat/pipelining/ kernel-only tuning knob (~40 total) is now a discoverable, optional Kconfig symbol shared with the hosted VM build. See Quick Start below.
Quick Start
# Build kernel (requires cross-compilation toolchain, or native gcc)
make -f Makefile.starkernel ARCH=amd64
# Run in QEMU with OVMF
make -f Makefile.starkernel qemu
# Other architectures
make -f Makefile.starkernel ARCH=aarch64 qemu
make -f Makefile.starkernel ARCH=riscv64 qemu
Artifacts: build/amd64/kernel/starkernel_loader.efi · build/amd64/kernel/starkernel_kernel.elf
For the hosted VM by itself (Linux, no cross-compiler needed, no bare-metal tooling): see
the separate StarForth repository — LithosAnanke used to be a branch inside that repo,
now it's its own project with its own master.
Build configuration (optional)
Every kernel-only knob (STARFORTH_ENABLE_VM, PARITY_MODE, the shared
physics/heartbeat family, etc.) is an optional Kconfig symbol — a plain
make -f Makefile.starkernel uses the same defaults it always has unless
you opt in:
make -f Makefile.starkernel ARCH=amd64 menuconfig
make -f Makefile.starkernel ARCH=amd64 kernel_amd64_defconfig
Documentation
| System Architecture | Full kernel + VM design |
| HAL Reference | Hardware abstraction layer interfaces |
| Capsule System — M7.1 | Capsule birth protocol design |
| VM Fleet Attractor design log | Tripod/Hermes/Artemis physics + build-system history |
| Getting Started / Kconfig reference | Full symbol reference for both build targets |
| Changelog | Milestone-level history |
| Roadmap | Milestone plan through self-hosting |
License
Starship License 1.0 (SL-1.0) — free for personal, research, and educational use. Commercial use requires a separate agreement. Attribution to R.A. James (Captain Bob) must be preserved in all distributions.
Patent pending. USPTO provisional filed December 2025 — physics-grounded self-adaptive runtime system. This license does not grant patent rights. Licensing inquiries: rajames440@gmail.com
Robert A. James (Captain Bob) · Systems Engineer · Hacking since 1973