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Polars DataFrame Assistant

Teaches Claude idiomatic Polars — expressions, lazy queries, and pandas-to-Polars migration.

Data & AnalyticsIntermediate★ 33,030⑂ 3,248AI score 8/10Last updated: Aug 9, 2026

What it does

Gives Claude working knowledge of Polars, the Arrow-backed high-performance DataFrame library. It covers expression building with pl.col(), LazyFrame query optimization (predicate and projection pushdown), group_by aggregations and over() window functions, joins/concat/pivot/unpivot, I/O for CSV, Parquet, JSON, Excel, databases and cloud storage, plus streaming execution for out-of-core data. Six reference files (core_concepts, operations, pandas_migration, io_guide, transformations, best_practices) are loaded on demand.

Who it's for

  • Analysts and engineers migrating pandas code to Polars
  • Anyone crunching multi-GB CSV/Parquet files on limited RAM
  • Developers tuning ETL pipeline throughput
  • Users who want Claude to emit real Polars idioms instead of pandas-in-disguise

Examples

  1. "Rewrite this pandas script with Polars LazyFrame" — drops the index, batches computations into with_columns, swaps read_csv for scan_csv.
  2. "From a 10GB parquet log, get average latency per city and the p95 tail" — produces a pushdown-optimized scan_parquet(...).group_by(...).agg(...).collect() query.
  3. "Pivot the sales table into date × product wide format, filling nulls with 0" — suggests pivot plus fill_null(0).

· · · Install guide · · ·

Install in the Claude app (no terminal)
  1. Download the ZIP with the button below.
  2. In Claude, open Settings → Capabilities and turn on 'Code execution and file creation'. (one time)
  3. Go to Customize → Skills → + → 'Upload a skill' and upload the ZIP.
↓ Download ZIP
Install in Claude Code

Let Claude do it — paste this into Claude Code

Install the skill I found on Claude Skill Mart.
Copy the skills/polars folder from the GitHub repo K-Dense-AI/scientific-agent-skills into my ~/.claude/skills/polars/.
When it's done, tell me in one line what this skill can do.

Install with a command instead

git clone https://github.com/K-Dense-AI/scientific-agent-skills.git /tmp/sas && mkdir -p ~/.claude/skills && cp -r /tmp/sas/skills/polars ~/.claude/skills/

⚠ This is a third-party skill. Check the source repository before installing.

  1. Open your terminal.
  2. Clone the repo: git clone https://github.com/K-Dense-AI/scientific-agent-skills.git
  3. Create the skills directory: mkdir -p ~/.claude/skills
  4. Copy the skill: cp -r scientific-agent-skills/skills/polars ~/.claude/skills/
  5. Install Polars: uv pip install "polars==1.41.2" (Python 3.10+ required)
  6. Optional extras: uv pip install "polars[excel,database,fsspec,pandas,numpy]==1.41.2"
  7. Restart Claude Code, then ask something like "Use Polars to aggregate this CSV" to trigger the skill.
View source on GitHub ↗License: MIT