Excellent. The alignment between the analyses is clear, and the provided feedback adds valuable tactical layers to the initial strategy. I’ve synthesized both documents into a single, unified action plan that incorporates the best ideas from both.
This is the most robust, performant, and resilient path forward.
Unified Action Plan: The Dynamic Signature System
Executive Summary
We are fully aligned. The core problem is the static, hard-coded question -> answer
string signature in dspy_bridge.py
, which discards the rich metadata from Elixir’s signature DSL. The solution is to refactor the Python bridge into a dynamic signature factory driven by a richer payload from Elixir.
This plan incorporates key tactical enhancements like resilient fallbacks and performance caching.
Key Enhancements from the Synthesis
- Resilient Fallback Mechanism: For backward compatibility and stability, if dynamic signature creation fails for any reason, the Python bridge will log a warning and fall back to the old
question -> answer
signature. This ensures the system never fully breaks. - Performance via Caching: To avoid the overhead of generating the same signature class repeatedly, the Python bridge will cache generated classes in memory. A hash of the signature definition will serve as the cache key.
- Granular TDD Approach: We will adopt a strict TDD approach, starting with a failing test for a multi-field signature to prove the system works end-to-end.
- Enriched Signature DSL: We will enhance the Elixir
DSPex.Signature
DSL to officially support field descriptions, which will be passed to DSPy.
Refined Code Implementation
Here are the critical code changes that combine the best of both analyses.
1. Python: dspy_bridge.py
(The Core Engine)
This refactor turns the bridge into an intelligent, dynamic, and cached factory.
# In dspy_bridge.py
import dspy
import time
import logging
# ... (rest of imports and setup) ...
class DSPyBridge:
def __init__(self, mode="standalone", worker_id=None):
"""Initialize the bridge with program registry and signature cache."""
self.programs = {}
# NEW: Cache for dynamically generated signature classes
self.signature_cache = {}
# ... (rest of init) ...
def _get_or_create_signature_class(self, signature_def: Dict[str, Any]) -> type:
"""
Gets a signature class from cache or creates it dynamically.
This is a performance optimization.
"""
# Create a stable key for caching
signature_key = json.dumps(signature_def, sort_keys=True)
if signature_key not in self.signature_cache:
debug_log(f"Cache miss for signature: {signature_key}. Creating new class.")
self.signature_cache[signature_key] = self._create_signature_class(signature_def)
return self.signature_cache[signature_key]
def _create_signature_class(self, signature_def: Dict[str, Any]) -> type:
"""Dynamically builds a dspy.Signature class from a detailed definition."""
class_name = signature_def.get('name', 'DynamicSignature').split('.')[-1].replace("_", "")
docstring = signature_def.get('description', 'A dynamically generated DSPy signature.')
attrs = {'__doc__': docstring}
# Dynamically create InputField and OutputField attributes
for field_def in signature_def.get('inputs', []):
field_name = field_def.get('name')
if field_name:
attrs[field_name] = dspy.InputField(desc=field_def.get('description', ''))
for field_def in signature_def.get('outputs', []):
field_name = field_def.get('name')
if field_name:
attrs[field_name] = dspy.OutputField(desc=field_def.get('description', ''))
# Use type() to create the class dynamically
return type(class_name, (dspy.Signature,), attrs)
def create_program(self, args: Dict[str, Any]) -> Dict[str, Any]:
"""Creates a new DSPy program using a dynamically generated signature."""
program_id = args.get('id')
signature_def = args.get('signature', {})
try:
# Use the new cached generator
DynamicSignatureClass = self._get_or_create_signature_class(signature_def)
program = dspy.Predict(DynamicSignatureClass)
except Exception as e:
# RESILIENT FALLBACK
debug_log(f"Dynamic signature creation failed: {e}. Falling back to Q/A.")
program = dspy.Predict("question -> answer")
DynamicSignatureClass = None # Indicate fallback was used
program_info = {
'program': program,
'signature_class': DynamicSignatureClass,
'signature_def': signature_def,
# ...
}
# ... (store program_info in self.programs or self.session_programs) ...
return {'program_id': program_id, 'status': 'created'}
def execute_program(self, args: Dict[str, Any]) -> Dict[str, Any]:
program_id = args.get('program_id')
inputs = args.get('inputs', {})
# ... (get program_info) ...
program = program_info['program']
signature_def = program_info['signature_def']
# This is the magic: unpacks the dict into named arguments
result = program(**inputs)
# Dynamically extract outputs
output_fields = [field['name'] for field in signature_def.get('outputs', [])]
outputs = {
name: getattr(result, name, None) for name in output_fields
}
return outputs
2. Elixir: Enriching the Signature & Payload
To power the Python factory, we need to send it a rich recipe.
dspex/signature/signature.ex
(Proposed DSL enhancement):
We can support descriptions by slightly modifying how we parse fields. A tuple {type, description}
can be used.
# In DSPex.Signature.Compiler, a small change to parse_fields_side
# would allow this intuitive syntax:
defmodule MySignature do
use DSPex.Signature
signature text: {:string, "The input text to analyze."},
style: {:string, "The desired style, e.g., 'formal' or 'casual'."}
->
sentiment: {:string, "The detected sentiment: positive, negative, or neutral."}
end
dspex/adapters/type_converter.ex
(The Payload Builder):
This module will now be responsible for creating the rich “recipe” for Python.
# In DSPex.Adapters.TypeConverter
def convert_signature_to_format(signature_module, :python, _opts) do
signature = signature_module.__signature__()
%{
"name" => to_string(signature.module),
"description" => get_module_doc(signature.module),
"inputs" => convert_fields_to_python_format(signature.inputs),
"outputs" => convert_fields_to_python_format(signature.outputs)
}
end
defp convert_fields_to_python_format(fields) do
Enum.map(fields, fn
# New pattern to extract description
{name, {type, desc}, _constraints} ->
%{"name" => to_string(name), "type" => to_string(type), "description" => desc}
# Existing pattern
{name, type, _constraints} ->
%{"name" => to_string(name), "type" => to_string(type), "description" => ""}
end)
end
# Helper to get @moduledoc
defp get_module_doc(module) do
case Code.get_doc(module, :moduledoc) do
{_line, doc} when is_binary(doc) -> doc
_ -> ""
end
end
Final Implementation Plan
This is a refined, actionable, week-by-week plan.
Week 1: Core Dynamic System (Get it working)
- Day 1: Implement the Python bridge changes in
dspy_bridge.py
:_create_signature_class
, cached_get_or_create_...
, and the resilientcreate_program
handler. - Day 2: Update the Elixir
TypeConverter
andSignature.Compiler
to support and send the enriched payload with descriptions. - Day 3-4: Write the first end-to-end integration test based on the TDD case below. Make it pass. This validates the entire pipeline.
- Day 5: Refactor and clean up.
Week 2: Production Hardening & Documentation
- Day 1-2: Rigorously test the caching and fallback mechanisms. Add performance benchmarks to confirm minimal overhead.
- Day 3-4: Update all documentation, especially
docs/SIGNATURE/2025*.md
, to reflect the new, superior architecture. Create a simple migration guide for users. - Day 5: Final review and merge.
The Key Test Case (TDD)
This test, written on Day 3, will drive the development and prove success.
# in test/dspex/signature_integration_test.exs
defmodule MultiOutputSignature do
use DSPex.Signature
@moduledoc "A signature for testing multiple outputs."
signature text: {:string, "The text to analyze."}
->
sentiment: {:string, "The sentiment of the text."},
language: {:string, "The detected language of the text."}
end
test "executes a program with a multi-output dynamic signature" do
# Use the python_port adapter for this test
adapter = DSPex.Adapters.Registry.get_adapter(:python_port)
# Ensure the LM is configured (can use mock for this)
adapter.configure_lm(%{model: "mock-model"})
# 1. Create the program
{:ok, prog_id} = adapter.create_program(%{
id: "multi_output_test_#{System.unique_integer()}",
signature: MultiOutputSignature
})
# 2. Execute the program
inputs = %{text: "I love coding in Elixir. It is a joy."}
{:ok, result} = adapter.execute_program(prog_id, inputs)
# 3. Assert the result has the correct structure
assert is_map(result)
assert Map.has_key?(result, "sentiment")
assert Map.has_key?(result, "language")
assert is_binary(result["sentiment"])
assert is_binary(result["language"])
# Example assertion (with a capable mock or real LM)
# assert result["language"] == "english"
end
Next Action: Begin the Python bridge refactor as outlined in Week 1, Day 1. This plan is clear, low-risk, and delivers immense value by unlocking the full potential of your signature system.