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+---
+phase: 3
+slug: printer-configuration
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-10
+---
+
+# Phase 3 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | pytest 8.x |
+| **Config file** | none — discovered via standard pytest directory scan |
+| **Quick run command** | `pytest tests/test_printer_crud.py -x -q` |
+| **Full suite command** | `pytest tests/ -v` |
+| **Estimated runtime** | ~5 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `pytest tests/test_printer_crud.py -x -q`
+- **After every plan wave:** Run `pytest tests/ -v`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 5 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 03-01-01 | 01 | 1 | PRNT-01, PRNT-02 | integration | `pytest tests/test_printer_crud.py::test_create_printer_persisted -x` | ❌ W0 | ⬜ pending |
+| 03-01-02 | 01 | 1 | PRNT-04 | integration | `pytest tests/test_printer_crud.py::test_create_printer_duplex -x` | ❌ W0 | ⬜ pending |
+| 03-01-03 | 01 | 1 | PRNT-05 | integration | `pytest tests/test_printer_crud.py::test_create_printer_color_mode -x` | ❌ W0 | ⬜ pending |
+| 03-01-04 | 01 | 1 | PRNT-06 | integration | `pytest tests/test_printer_crud.py::test_create_printer_paper_size -x` | ❌ W0 | ⬜ pending |
+| 03-01-05 | 01 | 1 | PRNT-07 | integration | `pytest tests/test_printer_crud.py::test_create_printer_collate -x` | ❌ W0 | ⬜ pending |
+| 03-01-06 | 01 | 1 | PRNT-09 | integration | `pytest tests/test_printer_crud.py::test_printer_survives_page_refresh -x` | ❌ W0 | ⬜ pending |
+| 03-02-01 | 02 | 1 | PRNT-08 | integration | `pytest tests/test_printer_crud.py::test_printer_grouped_by_client -x` | ❌ W0 | ⬜ pending |
+| 03-03-01 | 03 | 2 | PRNT-10 | integration | `pytest tests/test_printer_crud.py::test_printer_detail_shows_driver -x` | ❌ W0 | ⬜ pending |
+| 03-01-XX | 01 | 1 | PRNT-03 | manual | Manual browser test | n/a | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `tests/test_printer_crud.py` — stubs for PRNT-01 through PRNT-10 (integration tests)
+- [ ] `tests/test_client_crud.py` — stubs for client creation and listing (can merge into test_printer_crud.py)
+
+*Existing infrastructure covers framework and conftest.py — no new infrastructure needed.*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Alpine.js auto-populates port name from IP | PRNT-03 | Browser-side Alpine.js reactivity cannot be tested with pytest TestClient | 1. Open /printers/new 2. Type "192.168.1.100" in IP field 3. Verify port field shows "IP_192_168_1_100" 4. Edit port field manually 5. Change IP field 6. Verify port field keeps manual value |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 5s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending