Chapter 6

Framework Comparisons

A deep dive into the differences between DSPy and LangChain. Understand when to use "Programming over Prompting" versus "Workflow Orchestration".

DSPy vs. LangChain

The choice between DSPy and LangChain often comes down to philosophy:

  • LangChain focuses on orchestration. It connects LLMs to thousands of tools, APIs, and data sources. It is great for building agents that need to browse the web or query databases out-of-the-box.
  • DSPy focuses on optimization. It treats prompts as compiled bytecode. It is great for building high-quality pipelines where accuracy and reliability are paramount.

When to Choose What

Scenario Recommended Framework
Rapid Prototyping LangChain (due to rich tooling)
Complex Reasoning DSPy (automatic optimization)
Production Optimization DSPy (metric-driven improvement)
Data Integrations LangChain (lots of loaders)

Hybrid Architecture

You don't have to choose! A powerful pattern is to use LangChain for data loading and DSPy for core logic.

# 1. Use LangChain to load data
loader = PyPDFLoader("data.pdf")
docs = loader.load()

# 2. Use DSPy to process it intelligently
class Summarizer(dspy.Module):
    # ... optimized logic ...

optimizer = dspy.BootstrapFewShot(...)
program = optimizer.compile(Summarizer(), trainset=docs)