prefecthq / prefect
Prefect is a workflow orchestration framework for building resilient data pipelines in Python.
github.com/prefecthq/prefectIndexed at b749a67Up to date with upstream
About this codebase
This repository is a full-stack orchestration platform: it ingests workflow definitions and runtime events through the Python server/CLI and integration modules, transforms them into persisted orchestration state (flow runs, task runs, artifacts, logs, and events) via server APIs and worker execution, and outputs a running control plane exposed through REST endpoints plus two web UIs (`ui` and `ui-v2`) for monitoring and managing executions.
Written by gpt-5.4-nano from the index
4,839 files and 36,096 symbols in 14 modules, led by Python (1,863 files) and TypeScript (1,574).
Code health
This codebase scores 7.6 out of 10 for code health, which we rate good. It also scores maintainability 7.9 and static performance 9.8 out of 10. The three are scored separately and never blended into one number. Risk is concentrated, as it usually is: 73 of 4,839 files are git hotspots, and they average 3.9 — which is where the fixes pay off most.
On the leaderboards:#1 of 3 Workflow orchestrators#9 of 44 Python repos
Do next
1 thing worth doing this quarter.
Worth planning
Delete 173 unused symbols and files (7,506 lines)
Nothing in the graph reaches them, across 77 files; every reader and agent pays to skip them.
- symbols
- 173
- lines
- 7,506
- safe to delete
- Yes(inferred)
Medium effort
Improve what Repowise can see
Add a test coverage report
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- line coverage
- Unknown, no report
Small effortReview the 292 proposed decisions
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- 292
- accepted
- 0
Medium effort
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[](https://repowise.dev/repo/prefecthq/prefect?src=badge_card)What is prefect?
prefect is a workflow orchestration framework for building resilient data pipelines in Python. It turns Python scripts into workflows that can use scheduling, caching, retries, dependencies, branching logic, and event-based automations. The repository uses Python for orchestration and includes TypeScript and JavaScript web interfaces.
Written by a model from the README and the index
Key features of prefect
- Prefect lets Python data pipelines use scheduling, caching, retries, and event-based automations.
- Prefect workflows can handle retries, dependencies, and complex branching logic.
- Prefect tracks workflow activity through a self-hosted server instance or Prefect Cloud dashboard.
- Prefect deployments can run workflows on a schedule, manually from the UI or CLI, or in response to events.
How prefecthq/prefect works
Workflow definitions and runtime events enter through the Python server, CLI, and integration modules. The src directory defines typed API contracts, validators, type aliases, and REST payload schemas used by the orchestration layer. Server APIs and workers transform workflow activity into persisted flow runs, task runs, artifacts, logs, and events. The prefect logging modules provide logging infrastructure, while prefect exceptions defines project exceptions. The ui and ui-v2 directories provide web interfaces for monitoring and managing executions. REST endpoints and the web interfaces expose the resulting orchestration state.
Prefect is a workflow orchestration framework for building resilient data pipelines in Python. This page is a map of the prefecthq/prefect repository, written primarily in Python, rebuilt from the source each time it is indexed. Repowise parses every symbol, computes a dependency graph, scores per-file code health from complexity, duplication, test coverage and churn, mines git history for hotspots and ownership, and lifts the architectural decisions into documentation you can read here or query through MCP.
The codebase has 4,839 files and 36,096 symbols in 14 modules, led by Python, TypeScript and Shell. Code health is 7.6 out of 10, rated good.
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Getting started with prefect
- Install Prefect with pip.
pip install -U prefect - Install Prefect with uv.
uv add prefect - Start a local Prefect server.
prefect server start
Commands copied from the README
prefecthq/prefect FAQ
What is prefect?
prefect is a Python workflow orchestration framework for building resilient data pipelines. It turns scripts into workflows with scheduling, retries, caching, and event-based automations.
How does prefect work?
prefect accepts workflow definitions and runtime events through its Python server, CLI, and integrations. Workers and server APIs persist execution state, which REST endpoints and web UIs expose for monitoring and management.
How do I install prefect?
Install prefect with pip install -U prefect or uv add prefect. Start a local server with prefect server start.
What language is prefect written in?
prefect is primarily written in Python. The repository also includes TypeScript and JavaScript code for its web interfaces.
How is the prefect code organized?
prefect is organized around the src directory, server and worker orchestration, integrations, tests, documentation, and the ui and ui-v2 web interfaces. Central Python files include prefect/__init__.py and prefect/logging/loggers.py.
When should I use prefect?
Use prefect to build and operate Python data pipelines that need scheduling, retries, caching, dependencies, branching, or event-based execution. Workflow activity can be monitored through a self-hosted server or Prefect Cloud.
What license does prefect use?
prefect uses the Apache-2.0 license.
Answers written by a model from the README and the index