hailo-backend-v0.2.0-iter227

ruvnet/RuVectorhailo-backend-v0.2.0-iter227May 4, 2026by ruvnet

AI Summary

Production-ready Hailo backend featuring extensive security hardening and the closure of integration gaps identified in ADR-178.

Key Highlights

Implements an eight-layer DoS gate stack with configurable environment variables.
Closes 6 of 8 integration gaps identified between Hailo backend and RuVector.
Achieves 9.6x throughput improvement over CPU fallback.
Stabilizes HEF binary compatibility with Pi 5 + AI HAT+.

New Features

Security hardening (DoS gates)
ADR-178 integration gap closure
Performance improvements (9.6x)
CI verification and audit checks
HEF binary compatibility

Full Release Notes

Branch `hailo-backend` snapshot at iter 227. NPU acceleration is the production default since iter 163.

## Performance (cognitum-v0, Pi 5 + AI HAT+, c=4 b=1)

| Metric | Value |
|---|---|
| Throughput | ~70 embeds/sec/worker |
| p50 latency | 55-57 ms |
| p99 latency | 86-90 ms (best clean runs) |
| vs cpu-fallback | 9.6× |
| NPU-bound ceiling | confirmed at ~70.6/sec (iter-179 saturation sweep) |

## Two arcs since v0.1.0-iter156b

### Arc 1 — Security / hardening (iters 174-213)

Eight-layer DoS gate stack on the gRPC worker, all env-tunable:

| Iter | Gate | Default |
|---|---|---|
| 180 | `RUVECTOR_MAX_REQUEST_BYTES` | 64 KB |
| 181 | `RUVECTOR_MAX_CONCURRENT_STREAMS` | 256 |
| 182 | `RUVECTOR_REQUEST_TIMEOUT_SECS` | 30 |
| 183 | CVE-2023-44487 rapid-reset cap | 32 |
| 184 | `RUVECTOR_HTTP2_KEEPALIVE_SECS` | 60 |
| 190 | `RUVECTOR_MAX_RESPONSE_BYTES` | 16 KB |
| 199 | `RUVECTOR_MAX_BATCH_SIZE` | 256 |
| 200 | Per-item rate-limit debit on streams | per-item |

Plus iter-174 HEF sha256 pin, iter-185 shutdown SEGV fix (5/5 SEGV → 10/10 clean), iter-191 HailoRT FFI 2s timeout, iter-209 retry short-circuit on terminal errors, iters 210-213 OOM-bounded operator-path file reads, iters 187-189 client TLS flag plumbing.

### Arc 2 — ADR-178 integration gap analysis (iters 215-227)

Goal-planner agent produced ADR-178 (459 lines) identifying 8 gaps; **6 closed**:

| Gap | Severity | Iter | Status |
|---|---|---|---|
| A | HIGH | 215 | ✅ ruvllm-bridge deploy artifacts |
| **B** | **HIGH** | **218 + 219** | **✅ `EmbeddingProvider` impl + workspace rejoin** |
| C | MEDIUM | 220 | ✅ short-term (csi-bridge docs disambiguation) |
| D | MEDIUM | 221 | ✅ short-term (`hailo-cluster-as-provider` example) |
| E | MEDIUM | 219 | ✅ folded into B |
| F | MEDIUM | 217 | ✅ ADR-167 stale stratigraphy collapsed |
| G | LOW | — | hardware-bound (Pi 4) |
| H | LOW | 216 | ✅ install-bridge.sh → install-mmwave-bridge.sh |

Plus three iter-219 follow-up side effects all caught + fixed (iters 224, 226, 227).

## Verification

- `cargo build --workspace --release`: clean (3m49s)
- `cargo check --workspace`: clean
- Cluster lib + integration tests `--features tls --test-threads=1`: 23 suites, all green; 120 lib tests
- hailo lib tests: 21 default + 22 cpu-fallback + 7 tokenizer pass
- `cargo deny check` on both hailo crates: advisories/bans/licenses/sources OK
- `cargo audit --deny warnings` with iter-224 ignores: exit 0
- Pi cognitum-v0 deployed + bit-identical embed verified
  (`vec_head=0.0181,-0.0220,0.0451,0.0159` unchanged)

## Companion artifacts

- ADR-178 (gap analysis): `docs/adr/ADR-178-ruvector-ruview-hailo-integration-gap-analysis.md`
- ADR-167 (master ADR, iter-217 collapse): `docs/adr/ADR-167-ruvector-hailo-npu-embedding-backend.md`
- HEF binary (compatible — unchanged from v0.1.0-iter156b): `hailo-encoder-v0.1.0-iter156b`

🤖 Generated with [claude-flow](https://github.com/ruvnet/claude-flow)