Install & Compatibility
Where this runs
tested against v2.10.1 · pip install
no network on importno background threads
Install × environment matrix
Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux
py 3.10
✕ build_error
✓ 6.4s
py 3.11
✕ build_error
✓ 5.8s
py 3.12
✕ build_error
✓ 5.6s
py 3.13
✕ build_error
✓ 5.6s
py 3.9
✕ build_error
✕ build_error
326MB installed
● package 326MB
Code
Verified usage
Verified import paths — ran on the pinned version, not inferred.
dy
✓ import dataframely as dy
✗ from dataframely import *
Top-level API uses `dy` prefix; wildcard imports pollute namespace and may conflict with `infer_schema` (removed from __all__ in v2.9.1)
Column
✓ from dataframely import Column
✗ from dataframely.column import Column
Column is re-exported at top-level; internal module paths are private and may change
Schema
✓ from dataframely import Schema
✗ from dataframely.schema import Schema
Schema is re-exported at top-level; internal module paths are private and may change
Quickstart: define a schema and validate a Polars DataFrame.
import polars as pl
import dataframely as dy
# Define a schema
schema = dy.Schema({
"name": dy.String(),
"age": dy.Int32(),
"email": dy.String().email(),
})
# Validate a DataFrame
df = pl.DataFrame({
"name": ["Alice", "Bob"],
"age": [30, 25],
"email": ["alice@example.com", "bob@example.com"],
})
result = schema.validate(df)
print(result.valid) # True
print(result.errors) # []
Errors
Common errors & fixes
AttributeError: module 'dataframely' has no attribute 'infer_schema'
`infer_schema` was removed from the top-level module's `__all__` in v2.9.1.
fixUse `dy.infer_schema` instead of relying on wildcard import. Ensure you have `import dataframely as dy`.
PolarsSchemaValidationError: Column 'email' not found in DataFrame
`validate` removes columns not in the schema unless `strict=False` is passed.
fixAdd missing columns to schema or pass `strict=False` to keep extra columns.
TypeError: unsupported operand type(s) for +: 'Decimal' and 'float'
Using float values for Decimal type constraints before v2.7.0.
fixUpgrade to dataframely >=2.7.0 or use integer values for Decimal constraints.
Upgrade
Version history
2.10.1latest on PyPI · released May 27, 2026
Audit
Dependencies
polarsrequiredCore dependency — dataframely validates Polars DataFrames