DSPex V2 Foundation - Requirements Specification
Document Information
- Version: 1.0.0
- Date: 2025-01-19
- Status: Draft
- Phase: Foundation (Initial Phase)
Executive Summary
DSPex V2 Foundation establishes the core infrastructure for a cognitive orchestration platform that bridges Elixir and Python’s DSPy framework. This initial phase focuses on creating a minimal but extensible foundation using Snakepit for Python process management, with a clean API that can route between native Elixir and Python implementations.
Functional Requirements
FR1: Core API Surface
FR1.1 Module Management
- FR1.1.1: Initialize and manage DSPy modules (Predict, ChainOfThought, ReAct)
- FR1.1.2: Support module configuration with typed parameters
- FR1.1.3: Enable module composition and chaining
- FR1.1.4: Provide module introspection capabilities
FR1.2 Signature System
- FR1.2.1: Parse DSPy signature syntax natively in Elixir
- FR1.2.2: Validate inputs/outputs against signatures
- FR1.2.3: Support field types and constraints
- FR1.2.4: Convert between Elixir and Python representations
FR1.3 Execution Interface
- FR1.3.1: Execute DSPy operations through a unified interface
- FR1.3.2: Support both synchronous and asynchronous execution
- FR1.3.3: Handle streaming responses from LLMs
- FR1.3.4: Provide execution context and metadata
FR2: Python Bridge via Snakepit
FR2.1 Pool Management
- FR2.1.1: Configure specialized Snakepit pools for different workloads
- FR2.1.2: Support multiple Python environments (lightweight, optimizer, GPU)
- FR2.1.3: Enable pool-specific resource constraints
- FR2.1.4: Implement health checking and pool monitoring
FR2.2 Communication Protocol
- FR2.2.1: Use JSON as default serialization format
- FR2.2.2: Support binary protocols for large data (MessagePack, Arrow)
- FR2.2.3: Implement request/response correlation
- FR2.2.4: Handle streaming responses
FR2.3 Session Management
- FR2.3.1: Create and manage stateful Python sessions
- FR2.3.2: Support session affinity for complex operations
- FR2.3.3: Enable session persistence across requests
- FR2.3.4: Implement session cleanup and lifecycle management
FR3: Native Implementations
FR3.1 Signature Processing
- FR3.1.1: Implement native signature parsing
- FR3.1.2: Support signature compilation and caching
- FR3.1.3: Provide signature validation without Python
- FR3.1.4: Enable signature introspection
FR3.2 Basic Operations
- FR3.2.1: Implement native template rendering
- FR3.2.2: Support native JSON Schema validation
- FR3.2.3: Provide native metric calculations
- FR3.2.4: Enable native response parsing
FR4: Routing and Orchestration
FR4.1 Smart Router
- FR4.1.1: Route operations to native or Python based on availability
- FR4.1.2: Support fallback mechanisms
- FR4.1.3: Enable manual routing overrides
- FR4.1.4: Track routing decisions for optimization
FR4.2 Pipeline Support
- FR4.2.1: Define pipelines mixing native and Python steps
- FR4.2.2: Support parallel execution across implementations
- FR4.2.3: Enable pipeline composition and reuse
- FR4.2.4: Provide pipeline execution monitoring
Non-Functional Requirements
NFR1: Performance
NFR1.1 Latency
- NFR1.1.1: Sub-100ms latency for simple operations
- NFR1.1.2: Sub-10ms overhead for routing decisions
- NFR1.1.3: Native operations must be 10x faster than Python equivalent
- NFR1.1.4: Support streaming with <50ms initial response time
NFR1.2 Throughput
- NFR1.2.1: Handle 1000+ requests/second for cached operations
- NFR1.2.2: Support 100+ concurrent Python operations
- NFR1.2.3: Scale linearly with pool size
- NFR1.2.4: Maintain performance under mixed workloads
NFR2: Reliability
NFR2.1 Fault Tolerance
- NFR2.1.1: Graceful degradation when Python processes fail
- NFR2.1.2: Automatic recovery from transient failures
- NFR2.1.3: Circuit breaker pattern for failing operations
- NFR2.1.4: No single point of failure
NFR2.2 Error Handling
- NFR2.2.1: Comprehensive error classification
- NFR2.2.2: Actionable error messages
- NFR2.2.3: Error recovery strategies
- NFR2.2.4: Error tracking and reporting
NFR3: Scalability
NFR3.1 Horizontal Scaling
- NFR3.1.1: Support distributed deployment
- NFR3.1.2: Pool size adjustable at runtime
- NFR3.1.3: Work distribution across nodes
- NFR3.1.4: Shared nothing architecture
NFR3.2 Resource Management
- NFR3.2.1: Memory limits per Python process
- NFR3.2.2: CPU throttling capabilities
- NFR3.2.3: GPU resource allocation
- NFR3.2.4: Automatic garbage collection
NFR4: Developer Experience
NFR4.1 API Design
- NFR4.1.1: Intuitive, Elixir-idiomatic API
- NFR4.1.2: Comprehensive documentation
- NFR4.1.3: Type specifications for all public functions
- NFR4.1.4: Helpful error messages
NFR4.2 Debugging
- NFR4.2.1: Detailed logging at multiple levels
- NFR4.2.2: Request tracing across systems
- NFR4.2.3: Performance profiling hooks
- NFR4.2.4: Interactive debugging support
NFR5: Compatibility
NFR5.1 DSPy Compatibility
- NFR5.1.1: Support DSPy 2.x API
- NFR5.1.2: Handle DSPy-specific data structures
- NFR5.1.3: Preserve DSPy semantics
- NFR5.1.4: Track DSPy version compatibility
NFR5.2 Elixir Ecosystem
- NFR5.2.1: OTP compliance
- NFR5.2.2: Phoenix integration ready
- NFR5.2.3: Nx tensor compatibility
- NFR5.2.4: Telemetry integration
Constraints
Technical Constraints
- TC1: Must use Snakepit for Python process management
- TC2: Initial phase limited to core DSPy modules
- TC3: Python 3.8+ required
- TC4: Elixir 1.14+ and OTP 25+ required
Business Constraints
- BC1: 4-week development timeline for foundation
- BC2: Must maintain backward compatibility path
- BC3: Open source with Apache 2.0 license
- BC4: Must support cloud deployment
Success Criteria
Functional Success
- All core DSPy modules accessible from Elixir
- Native and Python implementations seamlessly mixed
- Pipeline execution with performance monitoring
- Comprehensive test coverage (>90%)
Performance Success
- Meeting all latency targets
- Achieving throughput goals
- Successful load testing at scale
- Performance regression tests passing
Quality Success
- Zero critical bugs in production
- <1% error rate under normal load
- 99.9% uptime for core services
- Positive developer feedback
Dependencies
External Dependencies
- Snakepit (core dependency)
- Python 3.8+ with DSPy
- Jason for JSON encoding
- Telemetry for metrics
- Nx for tensor operations (optional)
Internal Dependencies
- None (fresh start)
Risks and Mitigations
Risk 1: Python Process Management Complexity
- Mitigation: Leverage Snakepit’s proven architecture
Risk 2: Serialization Overhead
- Mitigation: Multiple protocol support, automatic selection
Risk 3: Version Compatibility
- Mitigation: Version detection and adaptation layer
Risk 4: Performance Degradation
- Mitigation: Comprehensive benchmarking and monitoring
Future Considerations
Phase 2 Extensions
- Advanced DSPy patterns (tree-of-thoughts, self-correction)
- Multi-agent coordination
- Distributed optimization
- Real-time adaptation
Long-term Vision
- Cognitive orchestration platform
- Universal variable system
- Self-optimizing pipelines
- Production ML infrastructure