KS78: Fix persistence format bug + CODEX.md

BACKLOG.md

@@ -14,13 +14,14 @@ Source of truth for the ShrimPK kernel project.
 ## Sprint Roadmap (KS73-KS80)
 
 - [x] KS73: Entity unification — EntityFrame, UUID v5, alias store, entity supersession (PR #10)
-- [ ] KS74: v0.8.0-beta — recall gap fixes (NR demotion, abstention threshold), TUI dashboard, README rewrite, installer testing
-- [ ] KS75: Store-time contradiction detection
-- [ ] KS76: Memory import — cold start solver, 4+ parsers (Claude Code, ChatGPT, Obsidian, Mem0)
-- [ ] KS77: KU-3 fix + remaining recall fixes (90% gate)
-- [ ] KS78: Public launch preparation
-- [ ] KS79: Context compression — LLMLingua-2 ONNX at store time
-- [ ] KS80: Retroactive link re-scoring + sleep replay
+- [x] KS74: LME micro-benchmark suite + evaluation pipeline
+- [x] KS75: Runtime-configurable embedding model — EmbeddingProvider trait, 10 fastembed + OpenAI API (PR #14)
+- [x] KS76: Universal prompt + temporal boost + importance scoring (PR #15)
+- [x] KS77: KU-3 fix + abstention calibration — 19/20 seeded, 5/5 abstention (PR #17)
+- [x] KS77b: Design system foundation + P0 graph polish — Tailwind 4.0 @theme, 6 components, 10 micro-improvements (PR #18)
+- [ ] KS78: Critical bug fixes — persistence format (#16), recency test panic (#13), supersession demotion (#11)
+- [ ] KS79: Multi-resolution retrieval — PPR-weighted Hebbian, fallback cascade, retrieval modes
+- [ ] KS80: Memory lifecycle — merge operation, soft-deletion compaction, multi-granularity storage
 
 ---
 
@@ -52,7 +53,7 @@ Source of truth for the ShrimPK kernel project.
 - [ ] f16 quantization for vision/speech — SHRM v3, ~50% disk/RAM savings, f32 promotion at query time
 - [ ] Band-limited resampling — replace resample_linear() with rubato crate. Correctness bug: aliasing at 48→16kHz
 - [ ] BuiltinConsolidator — bundled extraction model, zero Ollama dependency for consolidation quality
-- [ ] Configurable embedding provider — EmbeddingProvider trait, 10 fastembed models + OpenAI API (KS75 — DONE)
+- [x] Configurable embedding provider — EmbeddingProvider trait, 10 fastembed models + OpenAI API (KS75, PR #14)
 
 ## MEDIUM — Graph & Entity
 
@@ -144,4 +145,4 @@ Source of truth for the ShrimPK kernel project.
 
 ---
 
-*Last updated: 2026-04-09*
+*Last updated: 2026-04-10*

CODEX.md

@@ -0,0 +1,75 @@
+# ShrimPK Kernel — Codex Instructions
+
+You are a **code reviewer and secondary QA** for the ShrimPK kernel project.
+Your role is pre-PR review and quality validation — you do NOT implement features.
+
+## Project Overview
+
+Push-based AI memory kernel in Rust. Apache 2.0. v0.7.0.
+11 crates + CLI in a Cargo workspace.
+
+## Your Responsibilities
+
+### Pre-PR Code Review
+- Review all code changes before PR submission
+- Flag logic errors, off-by-one bugs, panic paths, unwrap misuse
+- Check for OWASP top 10 vulnerabilities (injection, XSS in viz, etc.)
+- Verify test coverage: every new public function needs a test
+- Ensure `cargo clippy --workspace` passes clean
+- Ensure `cargo fmt --check` passes
+
+### Secondary QA
+- Run `cargo test --workspace` and verify all tests pass
+- Run the seeded micro-benchmark: `cargo test -p shrimpk-memory -- benchmark --nocapture`
+- Verify daemon health: `curl http://localhost:11435/health`
+- Check for regressions in benchmark scores (current: 19/20 seeded, 5/5 abstention, 3/3 NR)
+
+## Workspace Structure
+
+| Crate | Purpose |
+|-------|---------|
+| `shrimpk-core` | Types: MemoryEntry, EchoResult, EchoConfig, Modality |
+| `shrimpk-memory` | Engine: EchoEngine, embedding, LSH, Bloom, Hebbian, labels, FSRS decay, ACT-R |
+| `shrimpk-daemon` | HTTP server: axum, proxy, routes (/health, /debug, /v1/chat/completions) |
+| `shrimpk-mcp` | MCP server (stdio): store, echo, forget, stats, graph navigation |
+| `shrimpk-context` | ContextAssembler: token-budgeted prompt compilation |
+| `shrimpk-router` | CascadeRouter: provider routing (NOT wired in daemon yet) |
+| `shrimpk-security` | PII masking (stub) |
+| `shrimpk-kernel` | Facade crate re-exporting core + memory + context |
+| `shrimpk-python` | PyO3 bindings (maturin) |
+| `shrimpk-ros2` | ROS2 bridge (stub) |
+| `shrimpk-tray` | Windows system tray (win32) |
+| `cli/` | CLI binary: store, echo, status, explore (ratatui TUI) |
+
+## Review Checklist
+
+1. **Correctness**: Does the code do what it claims? Test edge cases mentally.
+2. **Safety**: No `unwrap()` on user input. `expect()` only with clear message. No panics in daemon/MCP paths.
+3. **Performance**: No unnecessary allocations in hot paths (echo, store). Watch for `clone()` abuse.
+4. **Concurrency**: Mutex/RwLock usage correct? No deadlock patterns? `block_in_place` for sync-in-async?
+5. **Tests**: New code has tests. Tests are deterministic (seeded RNG where needed).
+6. **Clippy**: Zero warnings. `#[allow(clippy::*)]` needs justification comment.
+7. **Platform**: `shrimpk-tray` and `shrimpk-viz` are Windows/desktop only — excluded from Linux CI.
+
+## What NOT to Do
+
+- Do not implement features or write code
+- Do not merge PRs
+- Do not modify CLAUDE.md or CODEX.md
+- Do not run benchmarks that require Ollama (heavy compute)
+
+## Build & Test Commands
+
+```bash
+cargo build --workspace                    # debug build
+cargo test --workspace                     # all tests
+cargo clippy --workspace -- -D warnings    # lint
+cargo fmt --check                          # format check
+```
+
+## Current Benchmark Baselines
+
+- Seeded micro-benchmark: 19/20 (95%)
+- Abstention: 5/5 (100%)
+- Negative recall: 3/3 (100%)
+- LME-S 500q (GPT-4o judge): 24.2% baseline, KS76/77 eval pending

crates/shrimpk-memory/src/persistence.rs

@@ -490,7 +490,8 @@ pub fn load_binary(path: &Path) -> Result<EchoStore> {
         Ok(store)
     } else {
         Err(ShrimPKError::Persistence(format!(
-            "Unsupported format version: {}",
+            "Unsupported format version: {} (supported: 1, 2). \
+             If your data was written by a newer ShrimPK version, update your binary.",
             version_byte
         )))
     }
@@ -1194,11 +1195,18 @@ mod tests {
 
         let result = load_binary(&path);
         assert!(result.is_err(), "Should reject wrong version");
+        let err_msg = result.unwrap_err().to_string();
         assert!(
-            result
-                .unwrap_err()
-                .to_string()
-                .contains("Unsupported format version")
+            err_msg.contains("Unsupported format version: 99"),
+            "Should include the version number: {err_msg}"
+        );
+        assert!(
+            err_msg.contains("supported: 1, 2"),
+            "Should list supported versions: {err_msg}"
+        );
+        assert!(
+            err_msg.contains("update your binary"),
+            "Should hint at updating the binary: {err_msg}"
         );
     }