Makes blk_vm_flush_all() (block_words.c) non-static and declares it in block_words.h -- it's already the entire implementation behind SAVE-BUFFERS (block_word_save_buffers() is a one-line wrapper), so sk_repl_idle() can call the exact same flush path outside word dispatch without duplicating any logic. Cheap every idle tick regardless of dirty state: every check inside is a small fixed-size scan, so no separate pre-check was needed on top of it. Caught a real bug via a live persistence test before trusting the feature: the first version gated the flush on sk_repl_get_active_vm() returning non-NULL, but NULL is that accessor's documented default (Tripod's own USE-redirect override, "restore default dispatch") -- without an active USE redirect, the flush silently no-op'd for the entire session. Confirmed live: wrote a byte via BUFFER (no UPDATE/SAVE-BUFFERS), waited past the idle cadence, killed QEMU abruptly, rebooted with the same disk image, read back 0 instead of the written 65. Fixed by threading the VM sk_repl_run()'s own loop already resolves each iteration (g_repl_active_vm ? g_repl_active_vm : vm) down as a parameter through sk_readline() into sk_repl_idle(), rather than trying to re-derive it from an accessor with the wrong default. Re-ran the same test after the fix: read back 65, matching the written byte -- the write survived an abrupt kill with no explicit flush call anywhere in the test, proving the idle-tick auto-flush genuinely ran. All three architectures re-verified clean. FABRIC-2.md Section V item 6 and the corresponding Milestone 3 punch-list item marked done. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01CXjAPTEKrgY2Mrk25KoLDn
capsules/
FORTH personality files loaded by the VM at boot. A capsule is an immutable, content-addressed payload; its XXHash64 hash is its identity. Any mutation changes the hash and the birth protocol rejects the image.
Key files
| File | Type | Purpose |
|---|---|---|
init.4th |
(m) MAMA_INIT |
Default Mama VM personality — loaded at LBN 2048 |
ACL.4th |
user | Word-level ACL system; self-activating at boot |
zuse.4th |
user | Bootstrap superuser; loaded by ACL.4th |
doe.4th |
user | DoE workload words (EXEC-DOE) — opt-in |
init-0.4th … init-9.4th |
(p) |
Numbered personality variants |
init-l8-*.4th |
(p) |
L8 Jacquard mode variants (stable/volatile/diverse/temporal/transition/omni) |
hermes/init.4th |
(p) |
Hermes baby VM personality |
artemis/init.4th |
(p) |
Artemis baby VM personality |
Block namespace
Block ranges are shared across all loaded capsules — collisions cause silent word-definition overwrites.
| Range | Owner |
|---|---|
| 2048–2099 | init.4th |
| 2100–2199 | doe.4th |
| 3000–3999 | workload capsules |
| 4000+ | user-defined (ACL.4th, zuse.4th, …) |
Each block is limited to 1024 bytes. Verify with wc -c before committing.
See also
experiments/bare_metal/README.md— DoE protocols and block namespace rulesdocs/03-architecture/word-acl/DESIGN.md— ACL system designtools/mkcapsule.c— assembles capsules intocapsule_generated.c- Project root