Source: https://seerepo.com/r/pola-rs/polars/built
Markdown source: https://seerepo.com/r/pola-rs/polars/built.md
Description: polars is a Rust repo built with Flask, flask-cors, and Tokio. It stores its data in object_store, pyarrow, pyiceberg, deltalake, and DuckDB.

# What is polars built with?

polars is a Rust repo built with Flask, flask-cors, and Tokio. It stores its data in object_store, pyarrow, pyiceberg, deltalake, and DuckDB, reaches it with SQLAlchemy, signs people in with azure-identity, uses AI through jax and torch, makes its content with xlsxwriter and openpyxl, validates its data with schemars and Pydantic, is tested with pytest-cov, pytest-xdist, Pytest, Hypothesis, proptest, and 1 more, deploys with boto3, and uses aiosqlite, polars-io, pylance, s3fs, adbc-driver-manager, and 3 more. It has 953,615 written lines, with 671 test files.

Read on November 6, 2026, at commit a2a4dea.

Repository: https://github.com/pola-rs/polars

## Frontend

### Styles

- **pydata-sphinx-theme**
- **sphinx-design**

### Interface

- **altair**: 3 files
- **comfy-table**: 1 file
- **[matplotlib](https://seerepo.com/uses/matplotlib)**: 1 file

## Backend

### Data

- **[aiosqlite](https://seerepo.com/uses/aiosqlite)**
- **polars-io**
- **pylance**
- **s3fs**
- **object_store**: 17 files
- **[pyarrow](https://seerepo.com/uses/pyarrow)**: 14 files
- **pyiceberg**: 10 files
- **deltalake**: 7 files
- **[DuckDB](https://seerepo.com/uses/duckdb)**: 2 files
- **adbc-driver-manager**: 1 file
- **adbc-driver-sqlite**: 1 file
- **lancedb**: 1 file
- **[SQLite](https://seerepo.com/uses/sqlite)**: 1 file · [py-polars/requirements-dev.txt, line 32](https://github.com/pola-rs/polars/blob/a2a4dea74ca08840c06cc7007f7d7e8d013af49f/py-polars/requirements-dev.txt#L32)

### Data access

- **[SQLAlchemy](https://seerepo.com/uses/sqlalchemy)**: 4 files

### Sign-in

- **[azure-identity](https://seerepo.com/uses/azure-identity)**: 1 file

### AI

- **jax**: 2 files
- **[torch](https://seerepo.com/uses/torch)**: 2 files

## Support

### The base

- **[Flask](https://seerepo.com/uses/flask)**
- **flask-cors**
- **[Tokio](https://seerepo.com/uses/tokio)**: 77 files

### Content

- **xlsxwriter**: 3 files
- **[openpyxl](https://seerepo.com/uses/openpyxl)**: 1 file

### Validation

- **[schemars](https://seerepo.com/uses/schemars)**: 117 files
- **[Pydantic](https://seerepo.com/uses/pydantic)**: 2 files

### Testing

- **pytest-cov**
- **pytest-xdist**
- **Pytest**: 390 files
- **Hypothesis**: 72 files
- **proptest**: 22 files
- **moto**: 2 files

### Deploy

- **[boto3](https://seerepo.com/uses/boto3)**: 2 files

### Tools

- **boto3-stubs**
- **maturin**
- **mypy**
- **Numba**
- **numpydoc**
- **pandas-stubs**
- **pip**
- **Ruff**
- **Sphinx**
- **sphinx-copybutton**
- **sphinx-sitemap**
- **syn**: 3 files
- **proc-macro2**: 2 files
- **num-derive**: 1 file
- **quote**: 1 file

### Other

- **cloudpickle**
- **msgpack**
- **Polars**
- **polars-arrow**
- **stacker**
- **strum**
- **tzdata**
- **serde**: 171 files
- **pyo3**: 137 files
- **num-traits**: 115 files
- **rayon**: 66 files
- **bytemuck**: 48 files
- **chrono**: 41 files
- **parking_lot**: 38 files
- **futures**: 36 files
- **strum_macros**: 32 files
- **either**: 28 files
- **hashbrown**: 27 files
- **rand**: 21 files
- **slotmap**: 21 files
- **serde_json**: 19 files
- **sqlparser**: 19 files
- **bytes**: 15 files
- **bitflags**: 14 files
- **chrono-tz**: 14 files
- **memchr**: 14 files
- **regex**: 12 files
- **async-trait**: 10 files
- **libc**: 10 files
- **indexmap**: 9 files
- **simd-json**: 9 files
- **simdutf8**: 8 files
- **NumPy**: 7 files
- **percent-encoding**: 6 files
- **uuid**: 6 files
- **blake3**: 5 files
- **itoa**: 5 files
- **ethnum**: 4 files
- **flate2**: 4 files
- **half**: 4 files
- **ndarray**: 4 files
- **regex-syntax**: 4 files
- **reqwest**: 4 files
- **aws-lc-rs**: 3 files
- **base64**: 3 files
- **crossbeam-queue**: 3 files
- **fs4**: 3 files
- **hex**: 3 files
- **pandas**: 3 files
- **snap**: 3 files
- **streaming-iterator**: 3 files
- **zmij**: 3 files
- **zstandard**: 3 files
- **zstd**: 3 files
- **atomic-waker**: 2 files
- **crossbeam-channel**: 2 files
- **crossbeam-utils**: 2 files
- **dyn-clone**: 2 files
- **foldhash**: 2 files
- **fsspec**: 2 files
- **gevent**: 2 files
- **lz4**: 2 files
- **lz4_flex**: 2 files
- **once_cell**: 2 files
- **pin-project-lite**: 2 files
- **rand_distr**: 2 files
- **rmp-serde**: 2 files
- **sysinfo**: 2 files
- **xxhash-rust**: 2 files
- **aho-corasick**: 1 file
- **arboard**: 1 file
- **async-channel**: 1 file
- **async-stream**: 1 file
- **bincode**: 1 file
- **boxcar**: 1 file
- **brotli**: 1 file
- **compact_str**: 1 file
- **crossbeam-deque**: 1 file
- **fastrand**: 1 file
- **getrandom**: 1 file
- **glob**: 1 file
- **libloading**: 1 file
- **libm**: 1 file
- **mimalloc**: 1 file
- **murmur3**: 1 file
- **orjson**: 1 file
- **pytz**: 1 file
- **serde-pickle**: 1 file
- **sha2**: 1 file
- **signal-hook**: 1 file
- **thiserror**: 1 file
- **thread_local**: 1 file
- **tikv-jemalloc-sys**: 1 file
- **tikv-jemallocator**: 1 file
- **unicode-normalization**: 1 file

## Other repos with a similar stack

- [ray-project/ray](https://seerepo.com/r/ray-project/ray/built): pylance, s3fs, pyarrow, pyiceberg, deltalake, Flask, flask-cors, pydata-sphinx-theme, sphinx-design, matplotlib, SQLAlchemy, azure-identity, jax, torch, openpyxl, Pydantic, boto3 · [Compare](https://seerepo.com/compare/pola-rs/polars/vs/ray-project/ray)
- [run-llama/llama_index](https://seerepo.com/r/run-llama/llama_index/built): aiosqlite, s3fs, pyarrow, pyiceberg, DuckDB, lancedb, SQLite, matplotlib, SQLAlchemy, azure-identity, torch, Pydantic, boto3 · [Compare](https://seerepo.com/compare/pola-rs/polars/vs/run-llama/llama_index)
- [apache/airflow](https://seerepo.com/r/apache/airflow/built): aiosqlite, pyarrow, pyiceberg, DuckDB, SQLite, Flask, SQLAlchemy, azure-identity, Pydantic, boto3 · [Compare](https://seerepo.com/compare/apache/airflow/vs/pola-rs/polars)
- [apache/superset](https://seerepo.com/r/apache/superset/built): pyarrow, Flask, flask-cors, matplotlib, SQLAlchemy, xlsxwriter, openpyxl, Pydantic, boto3 · [Compare](https://seerepo.com/compare/apache/superset/vs/pola-rs/polars)
- [datawhalechina/hello-agents](https://seerepo.com/r/datawhalechina/hello-agents/built): aiosqlite, SQLite, Flask, matplotlib, SQLAlchemy, torch, openpyxl, Pydantic · [Compare](https://seerepo.com/compare/datawhalechina/hello-agents/vs/pola-rs/polars)
- [open-webui/open-webui](https://seerepo.com/r/open-webui/open-webui/built): pyarrow, SQLite, SQLAlchemy, azure-identity, openpyxl, Pydantic, boto3 · [Compare](https://seerepo.com/compare/open-webui/open-webui/vs/pola-rs/polars)

## Frequently asked questions

### What language is polars written in?

polars is written in Rust, with 953,615 written lines.

### What framework does polars use?

polars is built with Flask, flask-cors, and Tokio.

### What database does polars use?

polars stores its data in object_store, pyarrow, pyiceberg, deltalake, and DuckDB and reaches it with SQLAlchemy.

### What does polars sign people in with?

polars signs people in with azure-identity.

### Does polars use AI?

Yes. polars uses AI through jax and torch.

### What services does polars use?

polars uses aiosqlite, polars-io, pylance, s3fs, adbc-driver-manager, adbc-driver-sqlite, lancedb, and SQLite.

### Does polars have tests?

Yes. polars has 671 test files and is tested with pytest-cov, pytest-xdist, Pytest, Hypothesis, proptest, and moto.

### Which repos have a stack like polars's?

The ones that share most of its stack: ray-project/ray, run-llama/llama_index, and apache/airflow.

## What is your repo built with?

Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.