diff --git a/README.md b/README.md
index 49f8978..da1550f 100644
--- a/README.md
+++ b/README.md
@@ -123,16 +123,45 @@ backup API).
 
 ## Roadmap
 
-Sub-project 2 (DB + reconciliation) is **shipped**. The other two:
+Sub-projects 2 and 3 are **shipped**. Next up:
 
-- **Sub-project 3 — More 837P/835 features.** Additional 837P validation
-  rules (REF*G1 enforcement, BHT06), 835 CAS deep-parsing, 999 ACK, and
-  270/271 eligibility.
+- **Sub-project 3 (shipped) — More 837P/835 features.**
+  - **837P validation rules:** R034 enforces `REF*G1` on frequency-code
+    7/8 claims; R035 enforces `BHT06` transaction-type-code is in the
+    allowed set per payer config.
+  - **835 CAS deep-parsing:** every CAS adjustment now surfaces with its
+    CARC reason code + label (e.g. `CO-29: The time limit for filing has
+    expired`), surfaced via `GET /api/remittances/{id}` and rendered as
+    an expansion row on the Remittances page.
+  - **999 ACK transaction set:** full inbound parser + outbound
+    serializer. Auto-generated on 837 ingest when `?ack=true` is passed
+    to `POST /api/parse-837`. Persisted to the `acks` table, browsable
+    on a new `/acks` page, and downloadable as the regenerated raw
+    999 text.
+  - **270/271 eligibility (API-only):** `POST /api/eligibility/request`
+    builds a 270 from a JSON payload (subscriber, provider, payer,
+    service type); `POST /api/eligibility/parse-271` ingests the
+    response and returns structured `coverage_benefits`.
 - **Sub-project 4 — Frontend features.** Per-claim detail drawer, batch
   diff view, real-time streaming of NDJSON GET responses, advanced
   filters (date range, multi-status, saved filter sets), keyboard-driven
   navigation.
 
+### SP3 endpoints
+
+- `POST /api/parse-837?ack=true` — existing 837 parse, plus optional
+  auto-generated 999 ACK persisted alongside the batch.
+- `POST /api/parse-999` — parse an inbound 999 ACK and persist it.
+- `GET /api/acks` — list ACKs.
+- `GET /api/acks/{id}` — ACK detail, including the regenerated
+  `raw_999_text`.
+- `POST /api/eligibility/request` — build a 270 from JSON.
+- `POST /api/eligibility/parse-271` — ingest a 271 and return parsed
+  coverage benefits.
+
+The UI gains a new **Acks** page (sidebar entry) that lists persisted
+ACKs and lets you download the regenerated 999 text.
+
 ## License
 
 No license file yet; this is internal-use software. Add a `LICENSE` file
diff --git a/docs/superpowers/plans/2026-06-20-cyclone-edi-features.md b/docs/superpowers/plans/2026-06-20-cyclone-edi-features.md
index ec34b39..0d2ba44 100644
--- a/docs/superpowers/plans/2026-06-20-cyclone-edi-features.md
+++ b/docs/superpowers/plans/2026-06-20-cyclone-edi-features.md
@@ -23,7 +23,7 @@
 by the parser, so R034 scans `raw_segments` for any segment whose first
 two elements are `["REF", "G1", ...]`. No new model field is required.
 
-- [ ] **Step 1: Add failing tests**
+- [x] **Step 1: Add failing tests**
 
 Append to `backend/tests/test_validator.py`:
 
@@ -45,12 +45,12 @@ def test_r034_ref_g1_required_when_freq_1_no_ref_g1_passes(strict_ref_g1_payer):
     # expect no error (rule only fires on 7/8)
 ```
 
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement `_r034_ref_g1_required` in `validator.py`**
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement `_r034_ref_g1_required` in `validator.py`**
   - Scan `claim.raw_segments` for `["REF", "G1", *]`; only check if claim
     frequency is 7 or 8; only emit if `cfg.require_ref_g1_for_adjustments`.
-- [ ] **Step 4: Register in `_RULES` list**
-- [ ] **Step 5: Commit**
+- [x] **Step 4: Register in `_RULES` list**
+- [x] **Step 5: Commit**
 
 ### Task 2: BHT06 transaction-type-code rule (R035)
 
@@ -71,34 +71,34 @@ def test_r034_ref_g1_required_when_freq_1_no_ref_g1_passes(strict_ref_g1_payer):
 > Set Purpose Code" (which is BHT02, qualifier 353). The plan originally
 > conflated these. Use `transaction_type_code` for the new `Envelope` field.
 
-- [ ] **Step 1: Add failing tests** — frequency_code=7/8 with no REF*G1 in raw_segments should NOT fire R034 (R034 is gated on `cfg.require_ref_g1_for_adjustments`, which is False for CO). Test must use a "strict" config.
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Add `transaction_type_code: str | None = None` to `Envelope` model**
-- [ ] **Step 4: Populate it in `_build_envelope` from `seg[6]` when present**
-- [ ] **Step 5: Implement `_r035_bht06_allowed` in `validator.py`**
+- [x] **Step 1: Add failing tests** — frequency_code=7/8 with no REF*G1 in raw_segments should NOT fire R034 (R034 is gated on `cfg.require_ref_g1_for_adjustments`, which is False for CO). Test must use a "strict" config.
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Add `transaction_type_code: str | None = None` to `Envelope` model**
+- [x] **Step 4: Populate it in `_build_envelope` from `seg[6]` when present**
+- [x] **Step 5: Implement `_r035_bht06_allowed` in `validator.py`**
   - If `claim.envelope.transaction_type_code` is set and not in
     `cfg.allowed_bht06`, emit error.
-- [ ] **Step 6: Register in `_RULES` list**
-- [ ] **Step 7: Commit**
+- [x] **Step 6: Register in `_RULES` list**
+- [x] **Step 7: Commit**
 
 ### Task 3: Verify existing R031 (REF*G1 optional) keeps no-op behavior
 
 **Files:**
 - Verify: `backend/src/cyclone/parsers/validator.py:54-57`
 
-- [ ] **Step 1: Read current `_r031_ref_g1_optional`**
-- [ ] **Step 2: Confirm it stays as a no-op (returns empty tuple)**
-- [ ] **Step 3: (No commit — verification task)**
+- [x] **Step 1: Read current `_r031_ref_g1_optional`**
+- [x] **Step 2: Confirm it stays as a no-op (returns empty tuple)**
+- [x] **Step 3: (No commit — verification task)**
 
 ### Task 4: Wire `require_ref_g1_for_adjustments` into CO Medicaid factory
 
 **Files:**
 - Verify: `backend/src/cyclone/parsers/payer.py:67`
 
-- [ ] **Step 1: Confirm factory sets the flag for CO (currently `False` for v1 leniency)**
-- [ ] **Step 2: Run existing co_medicaid fixture through new R034**
-- [ ] **Step 3: Adjust fixture or factory if false positives appear**
-- [ ] **Step 4: Commit if any change**
+- [x] **Step 1: Confirm factory sets the flag for CO (currently `False` for v1 leniency)**
+- [x] **Step 2: Run existing co_medicaid fixture through new R034**
+- [x] **Step 3: Adjust fixture or factory if false positives appear**
+- [x] **Step 4: Commit if any change**
 
 ### Task 5: Phase 1 commit + full suite
 
@@ -117,11 +117,11 @@ Expected: 205 + 6 = ~211 pass.
 - Create: `backend/src/cyclone/parsers/cas_codes.py`
 - Create: `backend/tests/test_cas_codes.py`
 
-- [ ] **Step 1: Add failing tests** for known/unknown lookup, count > 100
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement `reason_label` + `all_known_codes` with ~150 CARC codes**
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing tests** for known/unknown lookup, count > 100
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement `reason_label` + `all_known_codes` with ~150 CARC codes**
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 7: Extend `GET /api/remittances/{id}` to surface `adjustments`
 
@@ -130,13 +130,13 @@ Expected: 205 + 6 = ~211 pass.
 - Modify: `backend/src/cyclone/api.py`
 - Modify: `backend/tests/test_api_gets.py`
 
-- [ ] **Step 1: Add failing tests** (empty adjustments returns `[]`, populated returns `{group, reason, label, amount, quantity}`)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Add a `get_remit_with_adjustments` method to `CycloneStore`**
-- [ ] **Step 4: Update `to_ui_remittance` (or add `to_ui_remittance_detail`) to include adjustments array**
-- [ ] **Step 5: Update endpoint to use the new mapper**
-- [ ] **Step 6: Run tests to verify they pass**
-- [ ] **Step 7: Commit**
+- [x] **Step 1: Add failing tests** (empty adjustments returns `[]`, populated returns `{group, reason, label, amount, quantity}`)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Add a `get_remit_with_adjustments` method to `CycloneStore`**
+- [x] **Step 4: Update `to_ui_remittance` (or add `to_ui_remittance_detail`) to include adjustments array**
+- [x] **Step 5: Update endpoint to use the new mapper**
+- [x] **Step 6: Run tests to verify they pass**
+- [x] **Step 7: Commit**
 
 ### Task 8: Frontend Remit type + Remittances page adjustments expansion
 
@@ -144,11 +144,11 @@ Expected: 205 + 6 = ~211 pass.
 - Modify: `src/types/index.ts`
 - Modify: `src/pages/Remittances.tsx`
 
-- [ ] **Step 1: Add `adjustments?: { group, reason, label, amount, quantity }[]` to `Remittance`**
-- [ ] **Step 2: Update Remittances page to render adjustments expansion**
-- [ ] **Step 3: Add test** in Remittances.test.tsx
-- [ ] **Step 4: Verify build + tests pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add `adjustments?: { group, reason, label, amount, quantity }[]` to `Remittance`**
+- [x] **Step 2: Update Remittances page to render adjustments expansion**
+- [x] **Step 3: Add test** in Remittances.test.tsx
+- [x] **Step 4: Verify build + tests pass**
+- [x] **Step 5: Commit**
 
 ### Task 9: Phase 2 commit + full suite
 
@@ -167,32 +167,32 @@ Expected: ~215 backend, ~9 frontend.
 - Create: `backend/src/cyclone/parsers/models_999.py`
 - Modify: `backend/src/cyclone/parsers/__init__.py`
 
-- [ ] **Step 1: Implement model classes per spec §4.1**
-- [ ] **Step 2: Wire lazy re-exports**
-- [ ] **Step 3: Verify import + simple instantiation works** (1 sanity test)
-- [ ] **Step 4: Commit**
+- [x] **Step 1: Implement model classes per spec §4.1**
+- [x] **Step 2: Wire lazy re-exports**
+- [x] **Step 3: Verify import + simple instantiation works** (1 sanity test)
+- [x] **Step 4: Commit**
 
 ### Task 11: 999 parser
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/parse_999.py`
 
-- [ ] **Step 1: Add failing tests** with minimal_999.txt fixture (basic happy path)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement orchestrator** following `parse_835.py` pattern
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing tests** with minimal_999.txt fixture (basic happy path)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement orchestrator** following `parse_835.py` pattern
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 12: 999 serializer (outbound)
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/serialize_999.py`
 
-- [ ] **Step 1: Add failing round-trip test** (parse → serialize → parse → assert equal)
-- [ ] **Step 2: Run test to verify it fails**
-- [ ] **Step 3: Implement `serialize_999`** (ISA/GS/ST/AK1/[AK2/AK3/AK4/AK5*]/AK9/SE/GE/IEA)
-- [ ] **Step 4: Run test to verify it passes**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing round-trip test** (parse → serialize → parse → assert equal)
+- [x] **Step 2: Run test to verify it fails**
+- [x] **Step 3: Implement `serialize_999`** (ISA/GS/ST/AK1/[AK2/AK3/AK4/AK5*]/AK9/SE/GE/IEA)
+- [x] **Step 4: Run test to verify it passes**
+- [x] **Step 5: Commit**
 
 ### Task 13: `acks` table + ORM + migration
 
@@ -200,22 +200,22 @@ Expected: ~215 backend, ~9 frontend.
 - Create: `backend/src/cyclone/migrations/0002_acks.sql`
 - Modify: `backend/src/cyclone/db.py`
 
-- [ ] **Step 1: Add migration SQL** per spec §4.4
-- [ ] **Step 2: Add ORM model `Ack` to `db.py`**
-- [ ] **Step 3: Add `CycloneStore.add_ack(...)` method**
-- [ ] **Step 4: Run migration on a fresh DB; verify table exists**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add migration SQL** per spec §4.4
+- [x] **Step 2: Add ORM model `Ack` to `db.py`**
+- [x] **Step 3: Add `CycloneStore.add_ack(...)` method**
+- [x] **Step 4: Run migration on a fresh DB; verify table exists**
+- [x] **Step 5: Commit**
 
 ### Task 14: `POST /api/parse-999` endpoint
 
 **Files:**
 - Modify: `backend/src/cyclone/api.py`
 
-- [ ] **Step 1: Add failing tests** (parse + persist, returns summary)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Add endpoint** mirroring `parse-835` JSON path
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing tests** (parse + persist, returns summary)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Add endpoint** mirroring `parse-835` JSON path
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 15: Auto-generate 999 on 837 ingest via `?ack=true`
 
@@ -223,13 +223,13 @@ Expected: ~215 backend, ~9 frontend.
 - Modify: `backend/src/cyclone/api.py`
 - Modify: `backend/tests/test_api_parse_persists.py`
 
-- [ ] **Step 1: Add 3 failing tests** (default no ack, ack=true happy path, ack=true with rejected claims)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Add `ack: bool = Query(False)` param to `parse_837_endpoint`**
-- [ ] **Step 4: Build `BatchAckBuilder` that converts validation report to 999**
-- [ ] **Step 5: Persist `Ack` row, attach to response body**
-- [ ] **Step 6: Run tests to verify they pass**
-- [ ] **Step 7: Commit**
+- [x] **Step 1: Add 3 failing tests** (default no ack, ack=true happy path, ack=true with rejected claims)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Add `ack: bool = Query(False)` param to `parse_837_endpoint`**
+- [x] **Step 4: Build `BatchAckBuilder` that converts validation report to 999**
+- [x] **Step 5: Persist `Ack` row, attach to response body**
+- [x] **Step 6: Run tests to verify they pass**
+- [x] **Step 7: Commit**
 
 ### Task 16: Frontend `/acks` page + sidebar entry
 
@@ -241,14 +241,14 @@ Expected: ~215 backend, ~9 frontend.
 - Create: `src/pages/Acks.test.tsx`
 - Modify: `src/components/Sidebar.tsx`
 
-- [ ] **Step 1: Add `Ack` type to `src/types/index.ts`**
-- [ ] **Step 2: Add `api.listAcks()` + `api.getAck(id)` to `src/lib/api.ts`**
-- [ ] **Step 3: Create `useAcks` hook**
-- [ ] **Step 4: Create `Acks.tsx` page** with empty state, populated list, download button
-- [ ] **Step 5: Add sidebar nav entry with `CheckCircle2` icon**
-- [ ] **Step 6: Add tests** (1-2 cases: empty + populated)
-- [ ] **Step 7: Verify typecheck + build + tests pass**
-- [ ] **Step 8: Commit**
+- [x] **Step 1: Add `Ack` type to `src/types/index.ts`**
+- [x] **Step 2: Add `api.listAcks()` + `api.getAck(id)` to `src/lib/api.ts`**
+- [x] **Step 3: Create `useAcks` hook**
+- [x] **Step 4: Create `Acks.tsx` page** with empty state, populated list, download button
+- [x] **Step 5: Add sidebar nav entry with `CheckCircle2` icon**
+- [x] **Step 6: Add tests** (1-2 cases: empty + populated)
+- [x] **Step 7: Verify typecheck + build + tests pass**
+- [x] **Step 8: Commit**
 
 ### Task 17: Phase 3 commit + full suite
 
@@ -266,54 +266,54 @@ Expected: ~225 backend, ~10 frontend.
 **Files:**
 - Create: `backend/src/cyclone/parsers/models_270.py`
 
-- [ ] **Step 1: Implement model classes per spec §4.2**
-- [ ] **Step 2: Wire lazy re-exports**
-- [ ] **Step 3: Sanity test**
-- [ ] **Step 4: Commit**
+- [x] **Step 1: Implement model classes per spec §4.2**
+- [x] **Step 2: Wire lazy re-exports**
+- [x] **Step 3: Sanity test**
+- [x] **Step 4: Commit**
 
 ### Task 19: 271 response models + service-type-code dict
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/models_271.py`
 
-- [ ] **Step 1: Implement model classes per spec §4.3**
-- [ ] **Step 2: Add inline `SERVICE_TYPE_CODES` dict** (~50 codes)
-- [ ] **Step 3: Add `service_type_description(code)` helper**
-- [ ] **Step 4: Sanity test**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Implement model classes per spec §4.3**
+- [x] **Step 2: Add inline `SERVICE_TYPE_CODES` dict** (~50 codes)
+- [x] **Step 3: Add `service_type_description(code)` helper**
+- [x] **Step 4: Sanity test**
+- [x] **Step 5: Commit**
 
 ### Task 20: 270 request parser
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/parse_270.py`
 
-- [ ] **Step 1: Add failing tests** with minimal_270.txt fixture
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement orchestrator**
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing tests** with minimal_270.txt fixture
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement orchestrator**
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 21: 271 response parser
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/parse_271.py`
 
-- [ ] **Step 1: Add failing tests** with minimal_271.txt fixture (2 EB segments)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement orchestrator** with EB segment handling
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing tests** with minimal_271.txt fixture (2 EB segments)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement orchestrator** with EB segment handling
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 22: 270 request serializer (outbound)
 
 **Files:**
 - Create: `backend/src/cyclone/parsers/serialize_270.py`
 
-- [ ] **Step 1: Add failing round-trip test**
-- [ ] **Step 2: Run test to verify it fails**
-- [ ] **Step 3: Implement `serialize_270`**
-- [ ] **Step 4: Run test to verify it passes**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing round-trip test**
+- [x] **Step 2: Run test to verify it fails**
+- [x] **Step 3: Implement `serialize_270`**
+- [x] **Step 4: Run test to verify it passes**
+- [x] **Step 5: Commit**
 
 ### Task 23: `POST /api/eligibility/request` endpoint
 
@@ -321,22 +321,22 @@ Expected: ~225 backend, ~10 frontend.
 - Modify: `backend/src/cyclone/api.py`
 - Create: `backend/tests/test_api_eligibility.py`
 
-- [ ] **Step 1: Add failing test**
-- [ ] **Step 2: Run test to verify it fails**
-- [ ] **Step 3: Implement endpoint**
-- [ ] **Step 4: Run test to verify it passes**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add failing test**
+- [x] **Step 2: Run test to verify it fails**
+- [x] **Step 3: Implement endpoint**
+- [x] **Step 4: Run test to verify it passes**
+- [x] **Step 5: Commit**
 
 ### Task 24: `POST /api/eligibility/parse-271` endpoint
 
 **Files:**
 - Modify: `backend/src/cyclone/api.py`
 
-- [ ] **Step 1: Add 2 failing tests** (happy path + parse error)
-- [ ] **Step 2: Run tests to verify they fail**
-- [ ] **Step 3: Implement endpoint**
-- [ ] **Step 4: Run tests to verify they pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Add 2 failing tests** (happy path + parse error)
+- [x] **Step 2: Run tests to verify they fail**
+- [x] **Step 3: Implement endpoint**
+- [x] **Step 4: Run tests to verify they pass**
+- [x] **Step 5: Commit**
 
 ### Task 25: Fixtures + cross-parser round-trip test
 
@@ -344,11 +344,11 @@ Expected: ~225 backend, ~10 frontend.
 - Create: `backend/tests/fixtures/minimal_270.txt`
 - Create: `backend/tests/fixtures/minimal_271.txt`
 
-- [ ] **Step 1: Write minimal_270.txt fixture** (small valid 270 request)
-- [ ] **Step 2: Write minimal_271.txt fixture** (small valid 271 response with 2 EB segments)
-- [ ] **Step 3: Add round-trip integration test** (parse 270 → serialize → parse → assert equal)
-- [ ] **Step 4: Verify tests pass**
-- [ ] **Step 5: Commit**
+- [x] **Step 1: Write minimal_270.txt fixture** (small valid 270 request)
+- [x] **Step 2: Write minimal_271.txt fixture** (small valid 271 response with 2 EB segments)
+- [x] **Step 3: Add round-trip integration test** (parse 270 → serialize → parse → assert equal)
+- [x] **Step 4: Verify tests pass**
+- [x] **Step 5: Commit**
 
 ### Task 26: Phase 4 commit + full suite
 
@@ -370,23 +370,23 @@ Verify `docs/superpowers/specs/2026-06-20-cyclone-edi-features-design.md` is on
 **Files:**
 - Modify: `README.md`
 
-- [ ] **Step 1: Update Roadmap section** to mark SP3 shipped and describe 4 areas
-- [ ] **Step 2: Commit**
+- [x] **Step 1: Update Roadmap section** to mark SP3 shipped and describe 4 areas
+- [x] **Step 2: Commit**
 
 ### Task 29: End-to-end smoke
 
-- [ ] **Step 1: Clean DB**, start server, parse 837 with `?ack=true`
-- [ ] **Step 2: Confirm 999 in response + `acks` row in DB**
-- [ ] **Step 3: Parse 999 fixture**, confirm endpoint round-trips
-- [ ] **Step 4: Build 270 request** via API, paste into parser
-- [ ] **Step 5: Commit empty** `smoke: end-to-end SP3 flow passes`
+- [x] **Step 1: Clean DB**, start server, parse 837 with `?ack=true`
+- [x] **Step 2: Confirm 999 in response + `acks` row in DB**
+- [x] **Step 3: Parse 999 fixture**, confirm endpoint round-trips
+- [x] **Step 4: Build 270 request** via API, paste into parser
+- [x] **Step 5: Commit empty** `smoke: end-to-end SP3 flow passes`
 
 ### Task 30: Final cleanup + merge worktree to main
 
-- [ ] **Step 1: Verify worktree is clean**
-- [ ] **Step 2: Discard main's stale uncommitted changes** (if any)
-- [ ] **Step 3: Fast-forward merge `edi-features` into `main`**
-- [ ] **Step 4: Remove worktree + delete branch**
+- [x] **Step 1: Verify worktree is clean**
+- [x] **Step 2: Discard main's stale uncommitted changes** (if any)
+- [x] **Step 3: Fast-forward merge `edi-features` into `main`**
+- [x] **Step 4: Remove worktree + delete branch**
 
 ---