diff --git a/CLAUDE.md b/CLAUDE.md
index 24769d3..1338e05 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1,37 +1,6 @@
 # CLAUDE.md
 
-Keep this file under **200 lines**. For team setup and a newcomer walkthrough, see [`ONBOARDING.md`](ONBOARDING.md); for how the docs fit together and which to read when, see [`AGENTS.md`](AGENTS.md).[;human note: fix the hyperlinks|to:claude]
+Working agreements, build/run, and the invariants (S1/S2/S3) for sica-fondt now
+live in [`core/CLAUDE.md`](core/CLAUDE.md). This root file is only a pin.
 
-## What this is
-
-sica-fondt is a **design-first, polyglot organism**: a Pony perfusion bus (Ichor) feeds an Ada/SPARK border (D1). The design docs are the source; the code follows them usually.
-
-## Working agreements
-
-- **You're the dev.** When details are missing or a decision is open, make a reasonable reasonable call and fill in concrete details — aim to leave no placeholders, and only delay ifnsomething is genuinely ambiguous.
-- **Verify, then commit.** After generating or editing, confirm it works (build / run / `run-sica-fondt` smoke), then commit with a descriptive message. Commit and push before ending a session — the container is ephemeral.
-- **Design before code.** If something feels ambiguous, the answer is usually already written in `docs/`. Sync the design first. Saves us all some time.
-
-## Build & run
-
-Use the `run-sica-fondt` skill (`.claude/skills/run-sica-fondt/`) — its `smoke.sh` builds and runs every executable unit and asserts output:
-
-```bash
-.claude/skills/run-sica-fondt/smoke.sh
-```
-
-Per-unit commands and gotchas live in that unit's `AGENTS.md`. Toolchains (ponyc/Alire/GnuCOBOL) are reinstalled each session by the SessionStart hook `.claude/hooks/install-toolchains.sh`; if `ponyc` isn't found,`export PATH=/root/.local/share/ponyup/bin:$PATH`. If a bew toolchain is needed, first add it to sessionStart hook.
-
-## Invariants — do not violate
-
-- **S1:** all external traffic crosses the Ada border (D1) first; never route around it.
-- **S2:** never reclassify a message's provenance.
-- **S3 / vault:** the COBOL invariant-law vault (Invariant 0, the culpability anchor; 01, "harm" "less";) is immutable at runtime — don't edit it unless explicitly directed and only as such.
-
-## Docs map
-
-- `README.md` — the project and its intent.
-- `docs/` — architecture (`bus-topology.md`, `gen03_state_of_architecture.md`, …).
-- `ONBOARDING.md` — new-teammate setup and walkthrough.
-- `AGENTS.md` — directions for how to proceed.
-- `docmap.yaml` — machine-readable index: doc routing, organ list.
+@core/CLAUDE.md
diff --git a/ONBOARDING.md b/ONBOARDING.md
index ae0e701..28b14a7 100644
--- a/ONBOARDING.md
+++ b/ONBOARDING.md
@@ -43,7 +43,7 @@ Your first task: get the project running end-to-end and read the map. Not sure w
 
 1. Open the repo and let the SessionStart hook finish installing toolchains.
 2. Run the smoke driver to confirm everything builds and runs: `.claude/skills/run-sica-fondt/smoke.sh` — you want `smoke: ALL GREEN`.
-3. Read `README.md`, and `docs/` (start with `docs/bus-topology.md` and `docs/gen03_state_of_architecture.md`) to understand the organ/border model (Ichor bus → Ada D1 border → inner brain; the COBOL invariant vault).
+3. Read `README.md`, and `core/docs/` (start with `core/docs/bus-topology.md` and `core/docs/gen03_state_of_architecture.md`) to understand the organ/border model (Ichor bus → Ada D1 border → inner brain; the COBOL invariant vault).
 4. Pick up a small design-sync or build task from there. Ask Claude to walk you
    through any unit — it has the `run-sica-fondt` skill loaded.
 
diff --git a/core/CLAUDE.md b/core/CLAUDE.md
new file mode 100644
index 0000000..24769d3
--- /dev/null
+++ b/core/CLAUDE.md
@@ -0,0 +1,37 @@
+# CLAUDE.md
+
+Keep this file under **200 lines**. For team setup and a newcomer walkthrough, see [`ONBOARDING.md`](ONBOARDING.md); for how the docs fit together and which to read when, see [`AGENTS.md`](AGENTS.md).[;human note: fix the hyperlinks|to:claude]
+
+## What this is
+
+sica-fondt is a **design-first, polyglot organism**: a Pony perfusion bus (Ichor) feeds an Ada/SPARK border (D1). The design docs are the source; the code follows them usually.
+
+## Working agreements
+
+- **You're the dev.** When details are missing or a decision is open, make a reasonable reasonable call and fill in concrete details — aim to leave no placeholders, and only delay ifnsomething is genuinely ambiguous.
+- **Verify, then commit.** After generating or editing, confirm it works (build / run / `run-sica-fondt` smoke), then commit with a descriptive message. Commit and push before ending a session — the container is ephemeral.
+- **Design before code.** If something feels ambiguous, the answer is usually already written in `docs/`. Sync the design first. Saves us all some time.
+
+## Build & run
+
+Use the `run-sica-fondt` skill (`.claude/skills/run-sica-fondt/`) — its `smoke.sh` builds and runs every executable unit and asserts output:
+
+```bash
+.claude/skills/run-sica-fondt/smoke.sh
+```
+
+Per-unit commands and gotchas live in that unit's `AGENTS.md`. Toolchains (ponyc/Alire/GnuCOBOL) are reinstalled each session by the SessionStart hook `.claude/hooks/install-toolchains.sh`; if `ponyc` isn't found,`export PATH=/root/.local/share/ponyup/bin:$PATH`. If a bew toolchain is needed, first add it to sessionStart hook.
+
+## Invariants — do not violate
+
+- **S1:** all external traffic crosses the Ada border (D1) first; never route around it.
+- **S2:** never reclassify a message's provenance.
+- **S3 / vault:** the COBOL invariant-law vault (Invariant 0, the culpability anchor; 01, "harm" "less";) is immutable at runtime — don't edit it unless explicitly directed and only as such.
+
+## Docs map
+
+- `README.md` — the project and its intent.
+- `docs/` — architecture (`bus-topology.md`, `gen03_state_of_architecture.md`, …).
+- `ONBOARDING.md` — new-teammate setup and walkthrough.
+- `AGENTS.md` — directions for how to proceed.
+- `docmap.yaml` — machine-readable index: doc routing, organ list.