Refactor Synthesizer Stack 1/4: Foundation

[EmanueleDeRossi1]

Summary

Start the refactoring of synthesizer architecture to use composition pattern with BaseSynthesizer as infrastructure base and TemplateSynthesizer as orchestration layer.

Problem / Opportunity

Current synthesizer stack has duplicated code across multiple synthesizer classes (PromptSynthesizer, ConfigSynthesizer, etc.) and lacks clear separation of concerns. Need cleaner architecture with reusable components.

Users & Use Cases

• SDK developers maintaining synthesizer code
• Users creating custom synthesizers
• Use case: Cleaner, more maintainable synthesizer architecture

Proposal

Replace current synthesizer hierarchy with:

BaseSynthesizer

• Core base class (not used directly)
• Provides model management, progress tracking, common utilities
• Inherited by all synthesizers

TemplateSynthesizer

• Orchestration layer using composition pattern
• Delegates to specialized components:
  • TemplateLoader (template management)
  • TemplateRenderer (template rendering)
  • LLMExecutor (or similar component, or delegate it to utility functions: LLM execution with retry/batching
• Single synthesizer for all template-based synthesis

Acceptance Criteria

• BaseSynthesizer provides core infrastructure without business logic
• TemplateSynthesizer orchestrates synthesis pipeline via components
• TemplateLoader manages template discovery and validation
• TemplateRenderer handles template rendering
• LLMExecutor manages LLM calls with retry/batching
• ResponseParser handles response parsing
• All components are testable in isolation
• Existing synthesizer functionality preserved