docs: bring Fable back — ecosystem advisory map

11 links mapped across the Fable ecosystem:
- Bun in Rust (Fable 5 writes production Rust for Bun rewrite)
- Letta sleep-time compute (FlatLedger validation)
- fable5-methodology (53★), fable-mode (711★)
- LifeOS (16.5k★), oh-my-pi (16.8k★) — key competitors
- mattpocock/skills (161k★), davidondrej/skills (1.9k★)
- AI-Builder-Club/skills (813★), oh-my-opencode (done)
- Claude multi-agent docs (done)

Harness-over-prompts thesis validated at 16.8k★ scale.
No vendoring. Advisory only.

docs/receipts/README.md

@@ -44,6 +44,7 @@ Current authority order: **live receipt > committed receipt > memory**.
 - `kunchen-dotfiles-advisory-map-20260705.json` — maps Kun Chen's dotfiles video + repo (Nix-based Mac agentic setup) as advisory-only. Includes 10 Windows adaptation mappings (Nix→winget/WSL, Homebrew→Chocolatey, Zsh→PowerShell, Westerm→Windows Terminal, Herder→tmux, etc.). Validates: TRUTH.md reproducibility pattern, flat-ledger.ts global memory pattern, worktree-isolation.ts agent isolation pattern. No vendoring.
 - `claude-multi-agent-docs-advisory-map-20260709.json` — maps Claude Platform managed agents multi-agent docs as advisory-only. Auth-walled page (HTML extracted via curl, content in JSON hydration blob). Validates execution-pipeline primary/worker pattern. No code changes warranted.
 - `bun-in-rust-advisory-map-20260709.json` — maps Jarred Sumner's "Rewriting Bun in Rust" blog post as advisory-only. Key: Bun acquired by Anthropic (Dec 2025), rewritten from Zig to Rust using Claude Fable 5 for memory safety. Validates LLM-as-compiler pattern (Fable 5 wrote the Rust), verify-gate pattern (systematic prevention > one-off fixes), FlatLedger pattern (state must live outside unsafe context). 22M monthly downloads. 5 takeaways. No vendoring.
+- `fable-ecosystem-return-advisory-map-20260709.json` — Bringing it back. Maps 11 links across the Fable ecosystem: Bun in Rust (Fable 5 writes Rust), Claude multi-agent docs (primary/worker delegation), Letta sleep-time compute (FlatLedger pattern), fable5-methodology (53★), fable-mode (711★), LifeOS (16.5k★), oh-my-pi (16.8k★), mattpocock/skills (161k★), davidondrej/skills (1.9k★), AI-Builder-Club/skills (813★), oh-my-opencode (already mapped). Key: LifeOS and oh-my-pi are the most relevant competitors validating the harness-over-prompts thesis. No vendoring.
 
 ## Memory quarantine
 

docs/receipts/fable-ecosystem-return-advisory-map-20260709.json

@@ -0,0 +1,125 @@
+{
+  "schema": "fable.external_project.review.v1",
+  "id": "fable-ecosystem-return-advisory-map-20260709",
+  "title": "Bringing Fable Back \u2014 Ecosystem Advisory Map",
+  "source": {
+    "type": "multi-link batch",
+    "links": [
+      "https://bun.com/blog/bun-in-rust",
+      "https://platform.claude.com/docs/en/managed-agents/multi-agent",
+      "https://www.letta.com/blog/sleep-time-compute/",
+      "https://github.com/UnpaidAttention/fable5-methodology",
+      "https://github.com/mrtooher/fable-mode",
+      "https://github.com/AI-Builder-Club/skills",
+      "https://github.com/mattpocock/skills",
+      "https://github.com/davidondrej/skills",
+      "https://github.com/danielmiessler/LifeOS",
+      "https://github.com/opensoft/oh-my-opencode",
+      "https://github.com/can1357/oh-my-pi"
+    ],
+    "fetchedAt": "2026-07-09T02:53:57.583504+00:00"
+  },
+  "blogReviews": [
+    {
+      "blog": "Bun in Rust",
+      "url": "https://bun.com/blog/bun-in-rust",
+      "status": "already receipted",
+      "receipt": "bun-in-rust-advisory-map-20260709.json"
+    },
+    {
+      "blog": "Claude Managed Agents Multi-Agent",
+      "url": "https://platform.claude.com/docs/en/managed-agents/multi-agent",
+      "status": "already receipted",
+      "receipt": "claude-multi-agent-docs-advisory-map-20260709.json"
+    },
+    {
+      "blog": "Letta Sleep-time Compute",
+      "url": "https://www.letta.com/blog/sleep-time-compute/",
+      "status": "new",
+      "key": "AI agents think during downtime by rewriting memory state. Validates FlatLedger pattern."
+    }
+  ],
+  "externalProjectReviews": [
+    {
+      "repo": "UnpaidAttention/fable5-methodology",
+      "stars": 53,
+      "license": "unknown",
+      "description": "Transferable self-enforcing methodology for AI coding agents. Playbook, skills, contracted subagents.",
+      "relevance": "Directly validates delegated execution model (worktree + verify-gate). Transferable methodology = TRUTH.md.",
+      "action": "watch"
+    },
+    {
+      "repo": "mrtooher/fable-mode",
+      "stars": 711,
+      "license": "unknown",
+      "description": "Claude skill activating Fable-style behavior: multi-stage planning, sub-agent delegation, self-improvement.",
+      "relevance": "Directly validates execution-pipeline architecture. Multi-stage planning matches pipeline spec.",
+      "action": "watch"
+    },
+    {
+      "repo": "AI-Builder-Club/skills",
+      "stars": 813,
+      "license": "unknown",
+      "description": "Codebase harness + loop engineer.",
+      "relevance": "Skills-as-harness pattern validation.",
+      "action": "advisory"
+    },
+    {
+      "repo": "mattpocock/skills",
+      "stars": 161495,
+      "license": "MIT",
+      "description": "Skills for Real Engineers. Directly from .claude directory.",
+      "relevance": "Massive market validation of skills-as-config pattern. 161k stars.",
+      "action": "advisory"
+    },
+    {
+      "repo": "davidondrej/skills",
+      "stars": 1918,
+      "license": "MIT",
+      "description": "Access to David Ondrej personal agent skills.",
+      "relevance": "Individual agent skills repo pattern growing.",
+      "action": "advisory"
+    },
+    {
+      "repo": "danielmiessler/LifeOS",
+      "stars": 16510,
+      "license": "MIT",
+      "description": "General Purpose AI Harness. Coding, building, creating, business, life, work.",
+      "relevance": "MOST RELEVANT COMPETITOR. General-purpose AI harness same as fable-agent. Study architecture.",
+      "action": "study"
+    },
+    {
+      "repo": "opensoft/oh-my-opencode",
+      "stars": null,
+      "license": "MIT",
+      "description": "Already mapped at c4843c7. User says \"old but still good.\"",
+      "relevance": "Already receipted. Still valid for pattern reference.",
+      "action": "already receipted"
+    },
+    {
+      "repo": "can1357/oh-my-pi",
+      "stars": 16812,
+      "license": "MIT",
+      "description": "AI terminal agent: hash-anchored edits, tool harness, LSP, Python, browser, subagents.",
+      "relevance": "MOST RELEVANT COMPETITOR. Hash-anchored edits = verify-gate. Tool harness = execution-pipeline. Subagents = worktree-isolation.",
+      "action": "study"
+    }
+  ],
+  "ecosystemKeyTakeaways": [
+    "Fable ecosystem growing: fable5-methodology (53\u2605), fable-mode (711\u2605), oh-my-pi (16.8k\u2605). Community building Fable patterns.",
+    "LifeOS (16.5k\u2605) and oh-my-pi (16.8k\u2605) are key competitors. Both validate harness-over-prompts.",
+    "mattpocock/skills (161k\u2605) is biggest market signal for skills-as-config.",
+    "Sleep-time compute validates FlatLedger: state outside LLM context during idle.",
+    "No vendoring. Study LifeOS and oh-my-pi architecture."
+  ],
+  "advisoryOnly": true,
+  "noActionRequired": true,
+  "fableAgentStatus": {
+    "containers": 12,
+    "phase": 4,
+    "autoPatchProven": false,
+    "tests": "295 passing, 69 files",
+    "commit": "5dfd34b",
+    "receipts": 32
+  }
+}