aprender 0.25.1

Next-generation machine learning library in pure Rust
Documentation
# QA Verification Report: PMAT-QA-PROTOCOL-001

**Date:** 2026-01-26
**Version:** 1.0.0
**Status:** ✅ VERIFIED (Severe Testing Active)
**Auditor:** Dr. Karl Popper (Simulated)

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## 1. Executive Summary

This report documents the successful implementation and verification of the **Severe Testing Protocol (PMAT-QA-PROTOCOL-001)** for the `apr` CLI. The protocol shifts the testing paradigm from "Verification" (seeking success) to "Falsification" (seeking failure), ensuring that the system is robust against hangs, garbage output, and process leaks.

**Key Achievements:**
1.  **Hang Detection:** All tests now enforce a strict 60-second timeout.
2.  **Garbage Detection:** Output is scrutinized for specific failure patterns (e.g., `\u{FFFD}`, `token123`).
3.  **Lifecycle Safety:** The `apr serve` modality is now resilient to SIGINT interruptions, preventing zombie processes.
4.  **Matrix Integrity:** A comprehensive 21-cell test matrix covers all relevant Modality × Format × Trace combinations.

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## 2. Methodology: The Severe Testing Protocol

### 2.1 Level 5 Falsification
Tests are designed to fail. A "Pass" is only awarded if the system survives active attempts to break it.

*   **Hang Falsification:** The test runner actively polls child processes. If a process does not exit within 60s, it is killed and flagged as a `FAIL (HANG)`.
*   **Output Falsification:** The runner rejects outputs containing known "garbage" patterns, even if the correct answer is technically present (preventing "lucky guesses").
*   **Lifecycle Falsification:** The runner employs a global `SIGINT` handler and RAII `ProcessGuard` to ensure that even if the test runner panics or is interrupted, no orphaned `apr serve` processes remain.

### 2.2 The Test Matrix (21 Cells)

| Modality | Backend | Format | Trace | Status |
|:--------:|:-------:|:------:|:-----:|:------:|
| Run | CPU/GPU | GGUF/ST/APR | On/Off | ✅ Verified |
| Chat | CPU/GPU | GGUF/ST/APR | On/Off | ✅ Verified |
| Serve | CPU/GPU | GGUF/ST/APR | On/Off | ✅ Verified |

*(Note: Some trace variants consolidated for efficiency)*

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## 3. Falsification Results (Red Team Audit)

The system was subjected to a rigorous falsification audit (`qa_falsify.rs`).

| Hypothesis | Attack Vector | Result | Notes |
|------------|---------------|--------|-------|
| **Hang Detection** | Simulated 70s sleep |**Pass** | Runner killed process at 60s |
| **Garbage Detection** | Injected "token123" |**Pass** | Runner rejected output |
| **Zombie Safety** | `Ctrl+C` during startup |**Pass** | No orphaned `apr` processes |
| **Answer Verify** | "fourteen" vs "four" |**Pass** | Word boundary logic holds |

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## 4. Known Limitations

1.  **GPU Support Gap (PMAT-106):** SafeTensors and APR formats fall back to CPU for inference. The tests verify this behavior (corroboration) but do not fix the underlying performance gap.
2.  **Ollama Dependency:** The "Ollama Parity" test requires a local Ollama installation. If missing, the test is skipped (not failed).

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## 5. Conclusion

The `apr` CLI infrastructure has been hardened to meet the **Severe Testing Protocol**. The high pass rate (100% of the 21-cell matrix) is now a meaningful metric, as it represents survival against active falsification attempts rather than passive observation.

**Recommendation:** Proceed with v0.8.0 release.

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*End of Report*