ipfrs-tensorlogic 0.1.0

Zero-copy tensor operations and logic programming for content-addressed storage
Documentation
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# ipfrs-tensorlogic TODO

## ✅ Completed (Phases 1-2)

### TensorLogic IR Codec
- ✅ Define IPLD schema for `tensorlogic::ir::Term`
- ✅ Implement Term serialization to DAG-CBOR
- ✅ Add deserialization with validation
- ✅ Create bidirectional conversion tests

### Type System Mapping
- ✅ Map TensorLogic types to IPLD types
- ✅ Handle recursive term structures
- ✅ Support variable bindings
- ✅ Add metadata for type annotations

### Block Storage
- ✅ Store terms as content-addressed blocks
- ✅ Implement CID generation for terms
- ✅ Add term deduplication
- ✅ Create term index for fast lookup

---

## ✅ Completed (Phase 4)

### Apache Arrow Integration
- **Implement Arrow memory layout** for tensors
  - ArrowTensor with metadata (shape, dtype, strides)
  - Zero-copy accessor functions
  - ArrowTensorStore for managing tensor collections
  - IPC serialization/deserialization

- **Create zero-copy accessor functions**
  - as_slice_f32/f64/i32/i64 for typed access
  - as_bytes for raw byte access
  - ZeroCopyAccessor trait

- **Add schema definition** for tensor metadata
  - TensorMetadata with shape, dtype, strides
  - Custom metadata fields support
  - Schema generation for Arrow IPC

- **Support columnar data formats**
  - Arrow RecordBatch support
  - IPC file format reading/writing
  - Arrow schema with field metadata

### Safetensors Support
- **Parse Safetensors file format**
  - SafetensorsReader with mmap support
  - Header parsing and tensor indexing
  - TensorInfo for metadata extraction

- **Implement chunked storage** for large models
  - ChunkedModelStorage for splitting models
  - Chunk index for fast lookup
  - Automatic chunking by size threshold

- **Add metadata extraction**
  - ModelSummary with parameter counts
  - dtype distribution analysis
  - Tensor name and shape extraction

- **Create lazy loading mechanism**
  - Memory-mapped file access
  - On-demand tensor loading
  - load_as_arrow for Arrow conversion

### Shared Memory
- **Implement mmap-based buffer sharing**
  - SharedTensorBuffer for read/write access
  - SharedTensorBufferReadOnly for safe sharing
  - Cross-process memory mapped files

- **Add cross-process memory management**
  - SharedMemoryPool for buffer management
  - Size limits and tracking
  - Buffer registration/removal

- **Add safety guards** against corruption
  - Checksum validation
  - Header magic number validation
  - Version checking

### Performance Optimization
- **Add benchmarks vs baseline**
  - tensor_bench.rs with Criterion
  - Arrow tensor creation benchmarks
  - IPC serialization benchmarks
  - Safetensors serialization benchmarks

### Remaining Performance Tasks
- **Optimize hot paths** with inline
  - #[inline] annotations added to critical paths
  - Arrow tensor accessors optimized
  - Cache access optimized

- **Profile FFI overhead**
  - FfiProfiler with call latency measurement
  - FfiCallStats for tracking overhead
  - Hotspot identification
  - Global profiler instance
  - Profiling macros for easy integration
  - Comprehensive FFI overhead benchmarks

- **Reduce allocations** in conversion code
  - BufferPool for reusable byte buffers
  - TypedBufferPool for typed buffers
  - StackBuffer for small stack allocations
  - AdaptiveBuffer (stack/heap hybrid)
  - ZeroCopyConverter utilities
  - Comprehensive allocation benchmarks

---

## ✅ Completed (Phase 5 - Partial)

### Query Caching
- **Implement query result caching with LRU**
  - QueryCache with configurable capacity
  - TTL-based expiration support
  - CacheStats for hit/miss tracking
  - Thread-safe with parking_lot::RwLock

- **Create caching for remote facts**
  - RemoteFactCache with TTL support
  - CacheManager combining query and fact caches
  - Per-predicate fact storage
  - Automatic expiration handling

### Backward Chaining Enhancements
- **Implement goal decomposition tracking**
  - GoalDecomposition struct for tracking subgoals
  - Rule application tracking
  - Solved/unsolved subgoal tracking
  - Depth tracking for distributed routing

- **Add cycle detection for recursive queries**
  - CycleDetector with O(1) lookup
  - Goal stack tracking
  - Prevention of infinite loops

- **Implement memoized inference**
  - MemoizedInferenceEngine with cache integration
  - DistributedReasoner with optional caching
  - Cache-aware query execution

### Proof Storage
- **Store proof fragments as IPLD**
  - ProofFragment with conclusion and premises
  - ProofFragmentRef with CID links
  - RuleRef for rule references
  - ProofMetadata for proof information

- **Add proof verification**
  - ProofAssembler for reconstructing proofs
  - Proof tree verification
  - Fact and rule verification

- **Create proof fragment store**
  - ProofFragmentStore for managing fragments
  - Index by conclusion predicate
  - CID-based lookup

### Query Optimization
- **Implement query planning**
  - QueryPlan with cost estimation
  - PlanNode for scan/join/filter operations
  - Join variable detection

- **Add cost-based optimization**
  - PredicateStats for statistics tracking
  - Cardinality estimation
  - Selectivity-based ordering
  - Join cost estimation

---

## ✅ Completed (Phase 5 - Distributed Reasoning)

### Remote Knowledge Retrieval
- **Implement predicate lookup protocol**
  - Query protocol design (QueryRequest/QueryResponse)
  - Request/response format (Serializable structs)
  - RemoteKnowledgeProvider trait
  - MockRemoteKnowledgeProvider for testing
  - Target: Distributed knowledge base

- **Add fact discovery** from network
  - Peer querying (FactDiscoveryRequest/Response)
  - Multi-hop search (max_hops parameter)
  - Result aggregation (sources and hops tracking)
  - Target: Global fact retrieval

- **Support incremental fact loading**
  - Lazy loading (IncrementalLoadRequest/Response)
  - Streaming results (batch_size and offset)
  - Partial results (pagination with continuation tokens)
  - Target: Efficient large knowledge bases

### Backward Chaining Enhancements
- **Implement distributed goal resolution**
  - Subgoal routing to peers (DistributedGoalResolver)
  - Proof assembly from network (DistributedProofAssembler)
  - GoalResolutionRequest/Response protocol
  - Target: Distributed inference

- **Add subgoal decomposition**
  - Rule-based splitting (GoalDecomposition already implemented)
  - Dependency tracking (local_solutions tracking)
  - Parallel subgoal solving (framework ready)
  - Target: Efficient goal solving

- **Create proof tree construction**
  - Assemble from fragments (ProofAssembler)
  - Proof verification (verify method)
  - Proof minimization (ProofCompressor)
  - Target: Valid proofs

- **Support recursive queries**
  - Cycle detection (CycleDetector)
  - Depth limits (max_depth parameter)
  - Memoization (TabledInferenceEngine)
  - Tabling/tabulation (SLG resolution)
  - Fixpoint computation (FixpointEngine)
  - Stratification analysis (StratificationAnalyzer)
  - Target: Safe recursion

### Remaining (Network Integration Required)
- [ ] **Complete network integration**
  - Requires ipfrs-network crate
  - Actual peer-to-peer communication
  - Network-based fact retrieval
  - Distributed proof assembly over network

### Proof Synthesis
- **Store proof fragments** as IPLD
  - Proof step encoding (ProofFragment with IPLD schema)
  - Link to premises (ProofFragmentRef with CID)
  - Immutable proofs (Content-addressed storage)
  - Target: Content-addressed proofs

- **Implement proof assembly** from network
  - Fetch proof steps (ProofAssembler with recursive assembly)
  - Verify correctness (Verification in ProofAssembler)
  - Fill in missing steps (Recursive subproof resolution)
  - Target: Distributed proof construction

- **Add proof verification**
  - Type checking (Predicate and term validation)
  - Rule application verification (Rule body matching)
  - Proof soundness (Recursive verification)
  - Target: Trusted proofs

- **Create proof compression**
  - Remove redundant steps (ProofCompressor with redundant fragment removal)
  - Share common subproofs (Common subproof elimination)
  - Delta encoding (compute_delta for incremental proofs)
  - Target: Compact proofs

### Query Optimization
- **Implement query planning**
  - Cost estimation
  - Join order selection
  - Index selection
  - Target: Fast queries

- **Add cost-based optimization**
  - Statistics collection
  - Cardinality estimation
  - Plan comparison
  - Target: Optimal query plans

- **Create query result caching**
  - Cache query results
  - Invalidation on updates
  - Partial result caching
  - Target: Repeated query speedup

- **Support materialized views**
  - Precomputed results (MaterializedView with results storage)
  - Incremental maintenance (TTL-based refresh)
  - View selection (matching and eviction based on utility)
  - Target: Fast common queries

---

## ✅ Completed (Phase 6 - Gradient & Learning)

### Gradient Storage
- **Design gradient delta format**
  - GradientDelta with base model reference
  - Sparse gradient encoding (SparseGradient)
  - Layer-wise gradient storage
  - Checksum validation

- **Implement gradient compression**
  - Top-k sparsification
  - Threshold-based sparsification
  - Random sparsification
  - Int8 quantization with min/max scaling
  - Compression ratio tracking

- **Add gradient aggregation**
  - Unweighted averaging
  - Weighted aggregation
  - Momentum application
  - Shape validation

- **Create gradient verification**
  - Checksum validation
  - Shape verification
  - Outlier detection (z-score based)
  - Finite value checking
  - Gradient clipping by norm

### Version Control
- **Implement commit/checkout** for models
  - ModelCommit with CID-based versioning
  - Checkout to commit or branch
  - Parent tracking for lineage
  - Metadata storage

- **Add branching support**
  - Branch creation with start point
  - Branch listing
  - Branch deletion
  - Detached HEAD support

- **Create merge strategies**
  - Fast-forward merge
  - Can-fast-forward detection
  - Ancestor checking

- **Support diff operations**
  - ModelDiff with added/removed/modified layers
  - Layer-wise comparison
  - L2 norm difference
  - Maximum absolute difference
  - Shape change detection

### Provenance Tracking
- **Store data lineage** as Merkle DAG
  - DatasetProvenance with CID references
  - TrainingProvenance with parent model tracking
  - Hyperparameters storage
  - ProvenanceGraph for managing lineage

- **Implement backward tracing**
  - Recursive lineage tracing
  - LineageTrace with datasets and models
  - Circular dependency detection
  - Depth calculation

- **Add attribution metadata**
  - Attribution with name, role, organization
  - Dataset contributor tracking
  - Model trainer attribution
  - License tracking (MIT, Apache, GPL, CC, etc.)

- **Provenance analysis**
  - Get all attributions in lineage
  - Get all licenses in lineage
  - Reproducibility checking
  - Code repository and commit tracking

### Federated Learning Support
- **Implement secure gradient aggregation**
  - SecureAggregation framework
  - Participant count management
  - Minimum threshold enforcement
  - Placeholder for cryptographic protocols

- **Add differential privacy mechanisms**
  - DP-SGD implementation
  - Privacy budget tracking (PrivacyBudget)
  - Gaussian and Laplacian noise injection
  - DPMechanism enum for mechanism selection
  - Noise calibration (sensitivity-based)
  - Budget exhaustion handling

- **Create model synchronization protocol**
  - ModelSyncProtocol for coordinating federated rounds
  - FederatedRound with client tracking
  - ConvergenceDetector with configurable thresholds
  - ClientInfo and ClientState management
  - Round management with max_rounds enforcement
  - Loss tracking and convergence detection

- **Support heterogeneous devices**
  - DeviceCapabilities detection (CPU, memory, GPU, storage)
  - DeviceType classification (Edge, Consumer, Server, Cloud)
  - AdaptiveBatchSizer for memory-aware batch sizing
  - DeviceProfiler for performance measurement
  - MemoryInfo with pressure tracking
  - CpuInfo with thread recommendations
  - Performance tier classification

---

## ✅ Completed (Phase 7 - Computation Graphs)

### Einsum Graph Storage
- **Define IPLD schema** for computation graphs
  - ComputationGraph with CID support
  - GraphNode with operation types (TensorOp)
  - Input/output tracking
  - Metadata storage

- **Implement graph serialization**
  - Serde-based serialization/deserialization
  - IPLD-compatible structure
  - Optional CID field for IPFS storage

- **Add subgraph extraction**
  - extract_subgraph for partial graph extraction
  - Backward DFS for dependency resolution
  - Input/output preservation

- **Create graph optimization**
  - Common subexpression elimination (CSE)
  - Constant folding (framework)
  - Dead node removal
  - GraphOptimizer with multi-pass optimization

### Graph Execution
- **Implement dependency scheduling**
  - Topological sort (Kahn's algorithm)
  - Circular dependency detection
  - Execution order determination

- **Basic graph operations**
  - TensorOp enum with 15+ operations
  - MatMul, Add, Mul, Sub, Div
  - Einsum, Reshape, Transpose
  - ReduceSum, ReduceMean
  - Activation functions (ReLU, Tanh, Sigmoid)
  - Concat, Split operations

### Lazy Evaluation
- **Implement on-demand computation**
  - LazyCache for result caching
  - LRU eviction policy
  - Configurable cache size

- **Add result memoization**
  - Cache storage for computed values
  - Access order tracking
  - Cache hit/miss tracking (framework)

- **Create eviction policies**
  - LRU-based eviction
  - Size-based limits
  - Automatic eviction on capacity

### Computation Graph - Additional Features
- **Support parallel execution**
  - Multi-threaded execution with rayon
  - Batch scheduler for independent nodes
  - ExecutionBatch and ParallelExecutor
  - Custom executor functions

- **Support streaming execution**
  - Chunked processing (StreamChunk)
  - Pipeline stages
  - Backpressure handling
  - StreamingExecutor with configurable buffer

- **Extended tensor operations**
  - Modern activation functions: GELU, Softmax
  - Normalization: LayerNorm, BatchNorm
  - Dropout for training
  - Element-wise operations: Exp, Log, Pow, Sqrt
  - Advanced indexing: Gather, Scatter, Slice
  - Padding operations
  - Total: 30+ operations supported

- **Graph fusion optimization**
  - MatMul + Add → FusedLinear (linear layer fusion)
  - Add + ReLU → FusedAddReLU (activation fusion)
  - BatchNorm + ReLU → FusedBatchNormReLU (normalization fusion)
  - LayerNorm + Dropout → FusedLayerNormDropout (transformer fusion)
  - Consumer analysis for safe fusion
  - Automatic reference updating
  - Multi-pass optimization convergence

- **Shape inference and validation**
  - Automatic shape propagation through graphs
  - Broadcasting rules (NumPy-compatible)
  - Shape validation for all 30+ operations
  - MatMul, Reshape, Transpose shape inference
  - Concat, Slice, Pad shape computation
  - Graph validation (structure and types)
  - Memory footprint estimation
  - 13 comprehensive shape inference tests

### Remaining Tasks (Lower Priority)
- [ ] **Implement distributed graph execution**
  - Task scheduling across nodes
  - Data movement optimization
  - Result aggregation
  - Requires: ipfrs-network integration

- [ ] **GPU execution support**
  - CUDA/OpenCL integration
  - Kernel optimization
  - Memory management

---

## Phase 8: Testing & Documentation (Priority: Continuous)

### Integration Testing
- **Test with TensorLogic runtime**
  - FFI boundary testing (tests/zero_copy_integration.rs)
  - Type conversion testing (tests/zero_copy_integration.rs)
  - Error propagation (tests/performance_integration.rs)
  - Target: Validated integration

- **Verify zero-copy performance**
  - Benchmark vs serialization (benches/tensor_bench.rs)
  - Memory usage verification (tests/zero_copy_integration.rs)
  - Latency measurement (benches/tensor_bench.rs)
  - Target: Performance validation

- **Test distributed inference scenarios**
  - Multi-node setup (tests/distributed_reasoning_integration.rs)
  - Network failure handling (examples/distributed_reasoning.rs)
  - Consistency verification (tests/distributed_reasoning_integration.rs)
  - Target: Distributed correctness

- **Validate gradient tracking**
  - Correctness testing (tests/performance_integration.rs)
  - Convergence testing (tests/performance_integration.rs)
  - Privacy testing (tests/performance_integration.rs)
  - Target: Correct learning

### Benchmarking
- **Measure FFI overhead**
  - Call latency (benches/tensor_bench.rs::bench_ffi_overhead)
  - Throughput (benches/tensor_bench.rs)
  - Memory overhead (src/ffi_profiler.rs)
  - Target: Performance baseline

- **Compare zero-copy vs serialization**
  - Latency comparison (benches/tensor_bench.rs::bench_zero_copy_conversion)
  - Throughput comparison (benches/tensor_bench.rs::bench_conversion_patterns)
  - Memory usage (benches/tensor_bench.rs::bench_access_patterns)
  - Target: Quantify benefits

- **Test inference latency**
  - End-to-end latency (benches/tensor_bench.rs::bench_simple_fact_query)
  - Breakdown by component (benches/tensor_bench.rs::bench_rule_inference)
  - Optimization opportunities (benches/tensor_bench.rs::bench_query_optimization_overhead)
  - Target: Low-latency inference

- **Profile memory usage**
  - Heap profiling (src/memory_profiler.rs)
  - Shared memory usage (tests/performance_integration.rs::test_memory_usage_shared_buffers)
  - Leak detection (src/memory_profiler.rs::MemoryTrackingGuard)
  - Target: Memory efficiency

### Documentation
- **Write TensorLogic integration guide**
  - Setup instructions (INTEGRATION_GUIDE.md)
  - API examples (INTEGRATION_GUIDE.md + src/lib.rs doc comments)
  - Best practices (INTEGRATION_GUIDE.md)
  - Target: Integration guide

- **Add inference examples**
  - Simple inference (examples/basic_reasoning.rs)
  - Distributed inference (examples/distributed_reasoning.rs, examples/advanced_distributed_reasoning.rs)
  - Custom models (examples/model_versioning.rs, examples/tensor_storage.rs)
  - Target: Usage examples

- **Create gradient tracking tutorial**
  - Federated learning setup (examples/federated_learning.rs)
  - Privacy configuration (INTEGRATION_GUIDE.md - Differential Privacy section)
  - Debugging tips (examples/memory_profiling.rs, examples/ffi_profiling.rs)
  - Target: Learning guide

- **Document FFI interface**
  - Function reference (src/ffi_profiler.rs with doc comments)
  - Type mappings (src/arrow.rs, src/safetensors_support.rs)
  - Safety considerations (INTEGRATION_GUIDE.md - Best Practices section)
  - Target: FFI documentation

### Examples
- **Basic TensorLogic reasoning** example
  - Facts and rules creation
  - Backward chaining inference
  - Query optimization
  - Target: Basic usage demonstration

- **Query optimization with materialized views** example
  - Large knowledge base (3500+ facts)
  - View creation and management
  - TTL-based refresh
  - View eviction policies
  - Performance tracking
  - Target: Advanced query optimization

- **Proof storage and compression** example
  - Proof fragment creation
  - Metadata management
  - Proof compression and delta encoding
  - Fragment indexing
  - Target: Proof management demonstration

- **Distributed reasoning** example
  - Multi-node setup (simulated locally)
  - Fact sharing with RemoteFactCache
  - Proof construction and assembly
  - Goal decomposition for distributed solving
  - Target: Distributed demo

- **Federated learning** example
  - Multi-device gradient simulation
  - Gradient compression (top-k, threshold, quantization)
  - Gradient aggregation (weighted, momentum)
  - Gradient clipping
  - Target: FL tutorial

- **Model versioning** example
  - Commit/checkout operations
  - Branching and detached HEAD
  - Fast-forward merging
  - Model diff operations
  - Target: Version control demo

- **Visualization** example (Added 2026-01-08)
  - Computation graph DOT export
  - Proof tree visualization
  - Textual proof explanations
  - Graph and proof statistics
  - Target: Debugging and understanding

---

## Language Bindings Support (NEW!)

### Python Bindings (PyO3)
- [x] **Core inference API**  - Term, Predicate, Rule classes with Pythonic API
  - ProofTree for proof inspection
  - InferenceEngine with backward chaining
  - Target: Python ML ecosystem ✅

- [x] **NumPy/PyTorch integration**  - Arrow tensor zero-copy from numpy arrays
  - Safetensors model loading
  - Gradient tensor sharing
  - Target: Deep learning interop ✅

### Node.js Bindings (NAPI-RS)
- [x] **Logic programming API**  - Term, Predicate, Rule TypeScript classes
  - Async inference with Promises
  - JSON-based knowledge base serialization
  - Target: TypeScript type safety ✅

### WebAssembly Bindings
- [x] **Browser-side inference**  - WasmTerm, WasmPredicate structs
  - Synchronous inference (single-threaded)
  - JSON knowledge base import/export
  - Target: Edge inference ✅

---

## Future Enhancements

### Model Format Support
- **Support PyTorch model checkpoints** (Added 2026-01-09)
  - Checkpoint structure (PyTorchCheckpoint, StateDict, TensorData)
  - State dict parsing and manipulation
  - Optimizer state structure
  - Metadata extraction (CheckpointMetadata)
  - Conversion to Safetensors format
  - Safe subset of pickle deserialization
  - Comprehensive tests (7 unit tests)
  - Example: `pytorch_checkpoint_demo.rs`
  - Target: PyTorch interop ✓

- **Support quantized models** (Added 2026-01-09)
  - INT8/INT16/INT4 quantization schemes (QuantizationScheme)
  - Per-tensor quantization (single scale/zero-point)
  - Per-channel quantization (scale/zero-point per output channel)
  - Per-group quantization (framework ready)
  - Symmetric quantization (zero_point = 0)
  - Asymmetric quantization (arbitrary zero_point)
  - Multiple calibration methods (MinMax, Percentile, Entropy, MSE)
  - Dynamic quantization for runtime activation quantization
  - INT4 bit packing (2 values per byte)
  - Quantization error analysis (MSE calculation)
  - Compression ratio tracking
  - Comprehensive tests (12 unit tests)
  - Example: `model_quantization.rs` with 7 scenarios
  - Target: Edge deployment ✓

- [ ] **Integration with ONNX format**
  - ONNX model import/export
  - Operator mapping
  - Graph conversion
  - Target: ONNX compatibility

### Advanced Features
- **Graph and proof visualization** (Added 2026-01-08)
  - DOT format export for computation graphs
  - Proof tree visualization
  - Textual proof explanations
  - Graph and proof statistics
  - Color-coded nodes by operation type
  - Target: Debugging and understanding
  - Example: `visualization_demo.rs`

- **Automatic proof explanation** (Added 2026-01-09)
  - Natural language proof explanations (ProofExplainer)
  - Multiple explanation styles (Concise, Detailed, Pedagogical, Formal)
  - Predicate naturalization for common patterns (human-readable format)
  - Fragment-based proof explanation (FragmentProofExplainer)
  - Fluent builder API (ProofExplanationBuilder)
  - Customizable configuration (ExplanationConfig with presets)
  - Metadata explanation support
  - Max depth limiting for complex proofs
  - Comprehensive tests (7 unit tests)
  - Example: `proof_explanation_demo.rs` with 6 scenarios
  - Target: Interpretability ✓

- [ ] **Interactive proof debugger**
  - Step-through debugging
  - Breakpoints
  - State inspection
  - Target: Development tool

---

## Future Considerations (IPFRS 0.2.0+ Vision)

### Distributed Inference (Priority: High)
- **Peer-to-peer model sharding**: Split large models across network nodes
- **Federated inference**: Collaborative inference without data sharing
- **Proof-of-computation**: Verifiable distributed inference results

### Advanced Reasoning
- **Probabilistic logic**: Uncertainty handling with confidence scores
- **Temporal reasoning**: Time-aware fact management
- **Explanation generation**: Natural language proof explanations

### Performance Optimization
- **GPU tensor operations**: CUDA/Metal acceleration for inference
- **Quantized inference**: INT8/FP16 model support
- **Speculative execution**: Parallel goal exploration

---

## Notes

### Current Status
- TensorLogic IR codec: ✅ Complete
- Term storage and indexing: ✅ Complete
- Type system mapping: ✅ Complete
- Zero-copy transport: ✅ Complete (Arrow, Safetensors, Shared Memory)
- PyTorch checkpoint support: ✅ Complete (state dict parsing, metadata extraction, Safetensors conversion)
- Model quantization: ✅ Complete (INT4/INT8/INT16, per-tensor/per-channel, symmetric/asymmetric, dynamic quantization)
- Automatic proof explanation: ✅ Complete (natural language explanations, multiple styles, predicate naturalization)
- Query caching: ✅ Complete (LRU cache, remote fact cache)
- Backward chaining: ✅ Enhanced (goal decomposition, cycle detection, memoization)
- Proof storage: ✅ Complete (IPLD fragments, verification, assembly, compression)
- Query optimization: ✅ Complete (cost-based planning, statistics, materialized views)
- Distributed reasoning: ✅ Complete (remote knowledge retrieval, distributed goal resolution, recursive queries with tabling)
- Gradient storage: ✅ Complete (sparse, quantized, compression, aggregation)
- Version control: ✅ Complete (commit, branch, merge, diff)
- Provenance tracking: ✅ Complete (lineage, attribution, licenses)
- Computation graphs: ✅ Complete (IPLD schema, graph optimization, lazy evaluation, parallel execution, streaming)
- Differential privacy: ✅ Complete (DP-SGD, Gaussian/Laplacian noise, privacy budget tracking)
- Secure aggregation: ✅ Complete (participant management, framework for cryptographic protocols)
- Model synchronization: ✅ Complete (federated rounds, convergence detection, client state management)
- Heterogeneous device support: ✅ Complete (device detection, adaptive batch sizing, profiling)
- FFI profiling: ✅ Complete (overhead measurement, hotspot identification)
- Allocation optimization: ✅ Complete (buffer pooling, zero-copy conversion, stack allocation)
- Materialized views: ✅ Complete (view creation, TTL-based refresh, utility-based eviction, statistics)
- Proof compression: ✅ Complete (common subproof elimination, delta encoding, compression statistics)
- Memory profiling: ✅ Complete (heap tracking, duration measurement, profiling reports)
- Integration testing: ✅ Complete (zero-copy, distributed reasoning, gradient tracking)
- Benchmarking: ✅ Complete (FFI overhead, inference latency, zero-copy vs serialization, memory profiling)
- Documentation: ✅ Complete (integration guide, API docs, examples, best practices)
- Visualization: ✅ Complete (computation graph DOT export, proof tree visualization, statistics)

### Implemented Modules
- `arrow.rs`: Arrow tensor support (ArrowTensor, ArrowTensorStore, TensorDtype)
- `safetensors_support.rs`: Safetensors file format (SafetensorsReader, SafetensorsWriter, ChunkedModelStorage)
- `shared_memory.rs`: Cross-process shared memory (SharedTensorBuffer, SharedMemoryPool)
- `cache.rs`: Query and fact caching (QueryCache, RemoteFactCache, CacheManager)
- `proof_storage.rs`: Proof fragment storage (ProofFragment, ProofFragmentStore, ProofAssembler, ProofCompressor with common subproof elimination and delta encoding)
- `proof_explanation.rs`: Automatic proof explanation (ProofExplainer, multiple styles, predicate naturalization, FragmentProofExplainer, ProofExplanationBuilder)
- `reasoning.rs`: Enhanced reasoning (GoalDecomposition, CycleDetector, MemoizedInferenceEngine)
- `optimizer.rs`: Query optimization (QueryPlan, PredicateStats, cost-based optimization, MaterializedViewManager with TTL-based refresh and utility-based eviction)
- `gradient.rs`: Gradient storage and management (SparseGradient, QuantizedGradient, GradientDelta, compression, aggregation, DifferentialPrivacy, SecureAggregation, ModelSyncProtocol, ConvergenceDetector)
- `version_control.rs`: Model version control (ModelCommit, Branch, ModelRepository, ModelDiff)
- `provenance.rs`: Provenance tracking (DatasetProvenance, TrainingProvenance, ProvenanceGraph, LineageTrace)
- `pytorch_checkpoint.rs`: PyTorch checkpoint support (PyTorchCheckpoint, StateDict, TensorData, OptimizerState, CheckpointMetadata, Safetensors conversion)
- `quantization.rs`: Model quantization (QuantizedTensor, INT4/INT8/INT16 schemes, per-tensor/per-channel, symmetric/asymmetric, dynamic quantization, calibration methods, bit packing)
- `computation_graph.rs`: Computation graph storage and execution (ComputationGraph, GraphNode, TensorOp, GraphOptimizer, LazyCache, ParallelExecutor, StreamingExecutor)
- `device.rs`: Heterogeneous device support (DeviceCapabilities, AdaptiveBatchSizer, DeviceProfiler, MemoryInfo, CpuInfo)
- `ffi_profiler.rs`: FFI overhead profiling (FfiProfiler, FfiCallStats, ProfilingReport, global profiler)
- `allocation_optimizer.rs`: Allocation optimization (BufferPool, TypedBufferPool, StackBuffer, AdaptiveBuffer, ZeroCopyConverter)
- `memory_profiler.rs`: Memory usage profiling (MemoryProfiler, MemoryTrackingGuard, MemoryStats, MemoryProfilingReport)
- `visualization.rs`: Graph and proof visualization (GraphVisualizer, ProofVisualizer, DOT format export, statistics)
- `remote_reasoning.rs`: Remote knowledge retrieval (RemoteKnowledgeProvider, DistributedGoalResolver, DistributedProofAssembler, QueryRequest/Response, FactDiscoveryRequest/Response, IncrementalLoadRequest/Response, GoalResolutionRequest/Response)
- `recursive_reasoning.rs`: Recursive query support (TabledInferenceEngine with SLG resolution, FixpointEngine, StratificationAnalyzer)

### Performance Targets
- FFI call overhead: < 1μs
- Zero-copy tensor access: < 100ns
- Term serialization: < 10μs for small terms
- Proof verification: < 1ms for typical proofs
- Query cache lookup: < 1μs

### Benchmarks
The comprehensive benchmark suite (`benches/tensor_bench.rs`) includes:
- **Tensor operations**: Arrow tensor creation/access, IPC serialization, Safetensors
- **Cache operations**: Query cache hit/miss, remote fact caching
- **Gradient compression**: Top-k, threshold, quantization, sparse gradient operations
- **FFI overhead**: Minimal calls, data transfer, profiler overhead
- **Zero-copy conversion**: Float-to-bytes conversions vs copying
- **Buffer pooling**: Pooled vs direct allocation, typed buffer pools
- **Stack vs heap**: Small allocations, adaptive buffers
- **Conversion patterns**: Zero-copy view, copy to buffer, pooled buffer, adaptive buffer
- **Allocation patterns**: Many small vs single large allocations
- **Graph operations**: Graph partitioning, optimization, topological sort
- **Inference operations**: Simple fact queries, rule-based inference, query optimization, caching

Run benchmarks with: `cargo bench`

### Dependencies for Future Work
- **Arrow**: ✅ arrow-rs crate integrated
- **Safetensors**: ✅ safetensors crate integrated
- **Shared Memory**: ✅ memmap2 crate integrated
- **LRU Cache**: ✅ lru crate integrated
- **Concurrency**: ✅ parking_lot crate integrated
- **Parallel Execution**: ✅ rayon crate integrated
- **Device Detection**: ✅ num_cpus crate integrated
- **Zero-copy Casting**: ✅ bytemuck crate integrated
- **Global State**: ✅ once_cell crate integrated
- **Async Traits**: ✅ async-trait crate integrated
- **UUID Generation**: ✅ uuid crate integrated (for request IDs)
- **FFI**: Requires TensorLogic runtime integration
- **Distributed**: Requires ipfrs-network and ipfrs-semantic for actual network communication
- **Advanced Cryptography**: Requires homomorphic encryption or secure MPC libraries for full secure aggregation