Supported Python Libraries

The bundled runtime ships the CPython 3.14 standard library plus these third-party packages, including their native extensions compiled to WASI and statically linked:

import ijson
import jinja2
import matplotlib
import numpy as np
import pandas as pd
from PIL import Image
from pydantic import BaseModel

Notes:

• Matplotlib renders to in-memory buffers / files (e.g. savefig to the instance filesystem); there is no display backend.
• Pillow supports reading and writing common formats (PNG round-trips are covered by integration tests).
• Packages with native code cannot be pip installed into the runtime — WASI has no dynamic linking, so native extensions must be statically linked at build time. To add one, extend the build pipeline.
• Pure-Python packages can be added without rebuilding anything via in-memory modules or the resource pipeline.