Punch list §25 item 3.4 complete. stadium_density(cell_index) reads a header's heat and mass and returns heat / mass -- a division on demand from fields already stored in the cell, matching §19.3's "read, not computed by a scheduler" literally. Stays valid Q48.16 without a special fixed-point routine, since heat is already Q48.16 and mass is a plain integer divisor. mass == 0 and an out-of-range cell_index both return 0 rather than dividing by zero -- an empty or never-admitted slot has no footprint to be dense within. Deliberately not built here, per the item's own wording: finding the densest or least-dense resident (§19.3's admission/eviction comparison) is item 3.5's scope, not this one's. Nothing calls stadium_density() yet either. Verified: three-architecture boot (amd64, aarch64, riscv64), all reaching ok> with identical dict_hash=0x3d4e1daf289da94f matching the item-3.3 baseline. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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