Poetry and Vercel

Vercel is a cloud platform designed to simplify website and web application deployment and scaling, adopting a serverless approach to relieve developers from server management complexities. Renowned for supporting frontend frameworks like React, Vue.js, and Next.js, Vercel also facilitates the deployment of serverless functions written in Python, enabling the creation of full-stack applications. To deploy a Python project on Vercel, developers need to ensure their codebase includes all necessary Python files, a requirements.txt listing dependencies, along with configuration files and optional components like static assets and serverless functions.

Deploying with Poetry

However, if a Python project utilizes pyproject.toml and Poetry instead of requirements.txt, a few adjustments may be needed to accommodate Poetry's features for dependency declaration, version management, and other tasks.

Here is sample vercel.json file that can be used to deploy Poetry projects.

{
  "builds": [
    {"src": "/app/main.py", "use": "@black-raven/vercel-poetry"}
  ],
  "routes": [
    {"src": "/(.*)", "dest": "app/main.py"}
  ]
}

This JSON configuration specifies the builds and routes for a Vercel deployment, replacing the default @vercel/python builder with @black-raven/vercel-poetry for enhanced dependency management. It includes a single build configuration where the source is set to /app/main.py, utilizing the specified package for handling dependencies. Additionally, it defines a route configuration where any request to the root directory / or its subdirectories will be directed to app/main.py. This setup ensures that the main Python file is appropriately handled for deployment on Vercel using the custom @black-raven/vercel-poetry builder.