# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [1.21.0] - 2025-11-06

### Added

#### Multi-Language SDK Implementation
- **C implementation**: Complete C library with 33 comprehensive tests (445 LOC test code)
- **Rust FFI bindings**: Safe wrapper with 4 core tests + Criterion benchmarks (875 LOC)
- **Python SDK via Cython**: Pythonic API with comprehensive test suite (674 LOC)
- **C++ with MLX**: GPU-accelerated implementation for Apple Silicon
- **Go CGO integration**: Seamless C/Go interop for performance-critical paths

#### Photon/Emitter Refactoring
- Replaced Sampler/Sample pattern with light-themed Emitter/Emit architecture
- Implemented luminance tracking for performance-based node selection
  - Range: 10-1000 lux (twilight → bright daylight)
  - Base: 100 lux (office lighting)
  - Dynamic brightness adjustment: +10% on success, -10% on failure
- Performance-based weighting using brightness values for node selection

#### Quantum-Resistant Integration
- OP Stack quantum finality integration example (`examples/op_stack_quantum_integration.go`)
- Post-quantum cryptographic proofs:
  - ML-DSA-65 digital signatures
  - ML-KEM-1024 key encapsulation
  - Quantum-resistant Merkle tree implementation
- Layer 2 rollup integration with quantum-resistant finality guarantees

#### Examples and Documentation
- 7 progressive tutorial examples:
  - `01-simple-bridge`: Cross-chain transfer basics
  - `02-ai-payment`: AI-powered payment validation
  - `03-qzmq-networking`: Quantum-secure ZMQ messaging
  - `04-grpc-service`: gRPC service integration (planned)
  - `05-python-client`: Python SDK usage examples
  - `06-typescript-integration`: TypeScript SDK (planned)
  - `07-ai-consensus`: Full AI consensus orchestration
- Package-level documentation (`doc.go`) with comprehensive API docs
- ~8,000 lines of new documentation across examples and guides

### Changed

#### Architecture Improvements
- Moved 1,631 lines of marketplace code from `ai/` to `examples/ai-marketplace/`
- Consolidated duplicate structures (configs, interfaces, context)
- Net reduction of 672 lines through deduplication
- Clean, DRY, orthogonal package layout

#### Test Coverage Improvements
- AI package: 37.1% → 74.5% coverage (+37.4pp)
- Core consensus: 432/580 lines tested
- Removed untestable blockchain-dependent code to examples
- High-coverage packages maintained:
  - `utils/codec`: 100%
  - `version`: 100%
  - `protocol/flare`: 95.7%
  - `protocol/focus`: 91.1%
  - `protocol/horizon`: 88.9%
  - `protocol/wave`: 83.3%

### Performance

**AI Consensus Benchmarks** (Apple M1 Max, Go 1.24.5):
- Model decisions: 1.5 μs per decision (660K decisions/sec)
- Simple model learning: 628 ns per training example
- Feature extraction: 37 ns (zero allocations)
- Sigmoid operations: 5.6 ns (179M ops/sec)
- Memory efficiency: 912 bytes per decision, 18 allocations

**C Implementation**:
- 33/33 tests passing (100% pass rate)
- 1000 blocks processed in < 0.001 seconds
- Zero-copy operations where possible
- Minimal memory footprint

**Rust Implementation**:
- 4/4 tests passing (100% pass rate)
- Zero-cost abstractions
- Memory safety guarantees

**Multi-Language Status**:
| Language | Status      | Tests          | Test LOC |
|----------|-------------|----------------|----------|
| Go       | Production  | Full suite     | Core     |
| C        | Production  | 33 tests       | 445      |
| Rust     | Production  | 4 tests        | 875      |
| Python   | Research    | Comprehensive  | 674      |
| C++/MLX  | Development | In progress    | -        |

### Deprecated
- `Sampler`/`Sample` APIs in photon package (still functional, use `Emitter`/`Emit` for new code)

### Fixed
- Build compatibility across all language implementations
- Test coverage reporting for AI package
- Documentation gaps in protocol packages

### Security
- Quantum-resistant cryptography integration for Layer 2 rollups
- Post-quantum signature schemes (ML-DSA)
- Post-quantum key encapsulation (ML-KEM)

---

## [1.17.0] - 2025-01-12

### 🎉 Major Release: Multi-Language SDK with 100% Test Parity

This release introduces complete multi-language support for the Lux consensus engine with C, Rust, Python, and Go implementations, all achieving 100% test parity and comprehensive benchmarks.

### ✨ Features

#### Multi-Language Implementation
- **C Implementation**: High-performance native C library with optimized hash tables
- **Rust FFI Bindings**: Safe Rust wrapper with zero-cost abstractions
- **Python SDK (Cython)**: High-level Python bindings with Pythonic API
- **Go CGO Integration**: Conditional compilation with seamless switching

#### Quantum-Resistant Features
- OP Stack Integration with ML-DSA-65 and ML-KEM-1024
- Quantum-resistant Merkle trees
- Example implementation provided

#### Performance Achievements
- Per-second throughput figures from this release were retracted by the
  2025-11-10 SDK audit: the C/Rust/Python/Go SDKs measure data-structure
  insertion (or the Rust `u8` overflow bug), not consensus. The honest
  consensus-bound rate is ≈21K votes/sec (C FFI). See
  `.github/workflows/README.md` and the "Honest Assessment" block in `LLM.md`.

### 📊 Test Coverage
- 100% test parity across all 4 implementations
- 15 test categories with comprehensive coverage
- All performance targets exceeded

### 🔧 Technical Improvements
- Custom hash table for O(1) operations
- Thread-safe with read-write locks
- Vote caching for performance
- Memory-efficient implementations

### 📦 Installation
See README.md for detailed installation instructions for each language.

### 📈 Benchmarks
Run benchmarks with:
- C: `make benchmark`
- Rust: `cargo bench`
- Python: `python3 benchmark_consensus.py`
- Go: `go test -bench=.`

---

## Links

- [v1.21.0]: https://github.com/luxfi/consensus/releases/tag/v1.21.0
- [v1.17.0]: https://github.com/luxfi/consensus/releases/tag/v1.17.0