# PMAT v2.180.1 - Critical Hotfix

**Release Date**: October 29, 2025
**Type**: Hotfix Release
**Priority**: HIGH

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## Critical Bug Fix

### TDG Baseline Backend Issue

**Problem**: TDG baseline commands failed with "Sled backend not available" error because `TieredStore::new()` was hardcoded to use the deprecated sled backend.

**Impact**: 
- `pmat tdg baseline create` commands failed
- `pmat tdg baseline compare` commands failed  
- All TDG baseline functionality broken without sled-backend feature
- Affected all v2.180.0 users

**Root Cause**: 
- File: `server/src/tdg/storage.rs` lines 121, 128
- Hardcoded: `StorageBackendType::Sled`
- Should be: `StorageBackendType::Libsql` (default backend)

**Fix**:
- Changed `TieredStore::new()` to use `StorageBackendType::Libsql`
- Updated storage paths: `.pmat/tdg-warm.db` and `.pmat/tdg-cold.db`
- Also updated documentation comment from "Sled backend" to "Libsql backend"

**Files Changed**:
- `server/src/tdg/storage.rs` (3 lines)

---

## Installation

```bash
cargo install pmat --version 2.180.1
```

---

## Verification

After upgrading, verify the fix:

```bash
# Should now work without sled-backend feature
pmat tdg baseline create --output .pmat/test-baseline.json --path .

# Clean up test
rm .pmat/test-baseline.json
```

---

## Upgrade Recommendation

**All v2.180.0 users should upgrade immediately** to v2.180.1. The TDG baseline feature is completely broken in v2.180.0.

---

## Full Changelog

### Fixed
- **CRITICAL**: TDG baseline commands now work with default libsql backend (server/src/tdg/storage.rs)
  - Changed hardcoded `StorageBackendType::Sled` to `StorageBackendType::Libsql`
  - Updated storage paths to use `.db` extension
  - Commit: [to be added]

### No Other Changes
- All other v2.180.0 features unchanged
- No breaking changes
- No new features

---

## Timeline

- **v2.180.0 Released**: October 29, 2025 (morning)
- **Bug Discovered**: October 29, 2025 (during Sprint 67 dogfooding)
- **Bug Fixed**: October 29, 2025 (same day)
- **v2.180.1 Released**: October 29, 2025 (same day)

**Turnaround**: < 4 hours from discovery to hotfix release

---

## Credits

**Bug Discovery**: Claude Code (AI Assistant) during Sprint 67 TDG dogfooding
**Root Cause Analysis**: Five Whys methodology applied
**Fix**: Single-line change (Sled → Libsql) × 2 locations
**Verification**: Tested TDG baseline creation on PMAT codebase

---

## Contact

**Issues**: https://github.com/paiml/paiml-mcp-agent-toolkit/issues
**Documentation**: https://paiml.github.io/pmat-book/

---

**Version**: v2.180.1
**Release Date**: October 29, 2025
**Type**: Critical Hotfix
**Severity**: HIGH (TDG baseline feature completely broken in v2.180.0)
