ControlFlow (archived — use marvin)

Warnings

• breaking ControlFlow repository archived August 22, 2025. No more updates, bug fixes, or security patches. The controlflow PyPI package still installs but is dead.
  Fix: pip install marvin — marvin v3 supersedes controlflow entirely. All cf.* equivalents exist as marvin.*.
• breaking ControlFlow had a hard dependency on prefect which caused version conflicts with prefect 3.0.0. marvin removes this dependency.
  Fix: Migrate to marvin. No prefect dependency required for agent workflows.
• breaking @cf.flow decorator removed in marvin v3. Replace with marvin.Thread() context manager.
  Fix: with marvin.Thread(): marvin.run(...)
• gotcha ControlFlow used LangChain as its LLM backend. marvin v3 uses Pydantic AI — broader provider support but different configuration patterns.
  Fix: Remove LangChain dependencies. Configure providers via pydantic-ai settings.
• gotcha LLMs trained before mid-2025 will generate controlflow code (import controlflow as cf). This is dead code — redirect to marvin.
  Fix: Replace all 'import controlflow as cf' with 'import marvin'. Map cf.run → marvin.run, cf.Task → marvin.Task, cf.Agent → marvin.Agent.

Install

• pip install marvin Python (use this instead)
• pip install controlflow Python (archived — do not use for new projects)

Imports

• Migration to marvin

  import marvin
  
  # marvin.run replaces cf.run
  result = marvin.run('Write a short poem about AI')
  print(result)
  
  # marvin.Task replaces cf.Task
  from marvin import Task, Agent
  task = Task(instructions='Summarize this text', result_type=str)
  
  # marvin.Thread replaces cf.Flow
  with marvin.Thread():
      marvin.run('step one')
      marvin.run('step two')

  controlflow is archived. marvin v3 is the direct successor. cf.run → marvin.run, cf.Task → marvin.Task, cf.Agent → marvin.Agent, cf.Memory → marvin.Memory, @cf.flow → marvin.Thread() context manager.

Quickstart

Marvin v3 replacement for ControlFlow.

# controlflow is archived — use marvin instead
# pip install marvin
import marvin

# Direct equivalent of controlflow's cf.run
result = marvin.run('Write a short poem about artificial intelligence')
print(result)