Loads turtle.4th and doe.4th, defines SDK-VERSION/SDK-HELP into an SDK vocabulary, then calls FENCE once everything is loaded -- protecting the base wordset and both cookbook capsules from FORGET. Kernel-only (EXEC doesn't exist hosted), REPL-invoked via S" sdk.4th" EXEC, not part of init.4th's boot sequence. Verified before writing the capsule, not assumed: VOCABULARY/DEFINITIONS does not actually scope word visibility in this interpreter -- vm_find_word is a flat dictionary scan that never consults CONTEXT/CURRENT. Documented plainly in the HOWTO so this isn't mistaken for namespace isolation later. Block range 5109-5115 -- discovered along the way that user-block space is capped at [2048, 5120) by mkcapsule, tighter than expected. Verified: mkcapsule --lint clean, hosted-build trace runs SDK-HELP with zero attributable VM errors, zero build warnings and identical 1012/0/0 POST results with matching dict_hash on all three kernel architectures. HOWTO: docs/working/architecture/SDK-HOWTO-20260819.md Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
docs/working/architecture/
Living system-design documentation: physics engine, HAL, heartbeat,
pipelining, word-ACL, adaptive systems, getting-started, and dated
design/finding notes for individual VM subsystems. This is the working-tier
source material that docs/formal/scraps/architecture/ is generated from.
- 03-architecture/ — Core architecture reference:
OVERVIEW.md, plusadaptive-systems/,hal/,heartbeat-system/,physics-engine/,pipelining/,word-acl/subtrees. Has its ownREADME.md. - getting-started/ — New-user and developer setup
guides (
DEVELOPER.md,INSTALL.adoc,QUICKSTART.adoc,quick-start/). Has its ownREADME.md. - architecture-internals/ —
INIT_SYSTEM.adoc,MESSAGING.adoc. - build-and-tooling/ —
BUILD_OPTIONS.adoc,DOCUMENTATION_README.adoc,INIT_TOOLS.adoc. - doxygen/ —
DOXYGEN_QUICK_REFERENCE.adoc,DOXYGEN_STYLE_GUIDE.adoc. MAMA_FORTH_SUPERVISOR_ARCHITECTURE.adoc— Mama VM supervisor design.PHYSICS_CONE_OF_INFLUENCE_DESIGN.adoc,PHYSICS_CONTROL_SYSTEM_DESIGN.adoc,PHYSICS_SIGNAL_MAP.adoc— physics-engine control-system design notes.VM_FORMALIZATION_PLAN.adoc— plan for Isabelle/HOL VM formalization.heartbeat_csv_export.md— heartbeat CSV export design (implementation status tracked in.claude/CLAUDE.md).- Dated design/finding notes for the Tripod VMs:
ARTEMIS-BAM-ACCEPTANCE-*,ARTEMIS-BLOCK-PHYSICS-DESIGN-*,ARTEMIS-FREEMAP-CAPSULE-RESERVATION-GAP-*,CAPSULE-BLOCK-PERSISTENCE-BOUNDARY-FINDING-*,CAPSULE-LOADER-DEFINITIONS-ONLY-DESIGN-*,HERMES-MESSAGE-BLOCK-STORAGE-DESIGN-*,HERMES-MESSAGE-CHANNEL-PHYSICS-DESIGN-*,K-PUSH-DICTIONARY-SHADOWING-BUG-*,VM-FLEET-ATTRACTOR-DESIGN-*,VM-PHYSICS-DYNAMIC-FLEET-DESIGN-*.
See also
docs/03-architecture/README.md— the binding-constraint Tripod/ACL docs, distinct from this design-notes tree.docs/formal/scraps/README.md— the press-ready fragment tier this material feeds.- Project root