Add fast paths for series.arg_sort and dataframe.sort (#19872)
Much faster Series construction from subclasses of standard Python types (#20166)
Utilize the RangedUniqueKernel for Enum/Categorical (#20150)
Reduce memory copy when scanning from Python objects (#20142)
Construct Series for bytes/binary data 10x faster when dtype not explicitly set (#20157)
Don't instantiate validity mask when unneeded in Parquet (#20149)

✨ Enhancements

Retry with reloaded credentials on cloud error (#20185)
Support reading Enum dtype from csv (#20188)
Improve dtype inference and load for DataFrame cols constructed from Python Enum values (#20180)
Allow sorting of lists and arrays (#20169)
Add maintain_order parameter to joins (#20026)
Allow for to_datetime / strftime to automatically parse dates with single-digit hour/minute/second (#20144)
Issue warning when using to_struct() without a list of field names (#20158)
Experimental cloud write support (#20129)
Add lazy support for pl.select (#20091)
Enable view arrow export in write_delta (#20092)

🐞 Bug fixes

Don't trigger length check in array construction (#20205)
Allow row encoding for 32-bit architectures (e.g. WASM) (#20186)
Properly project unordered column in parquet prefiltered (#20189)
Csv stop simd cache if eol char is hit (#20199)
Estimated size for object (#20191)
Respect parallel argument in parquet (#20187)
Only validate UTF-8 for selected items when all below len 128 (#20183)
Serialize categories of Enum in arrow metadata (#20181)
Don't use RLE encoding for Parquet Boolean (#20172)
Invalid bitwise_xor for ScalarColumn (#20140)
Series construct with large nested u64 (#20167)
Add temporal feature gate in is_elementwise_top_level (#20177)
Column name mismatch or not found in Parquet scan with filter (#20178)
Raise if apply returns different types (#20168)
Deal with masked out list elements (#20161)
Fix index out of bounds in uniform_hist_count (#20133)
Implement arg_sort for Null series (#20135)
Handle slice pushdown in PythonUDF GroupBy (#20132)
Check shape for *_horizontal functions (#20130)
Properly coerce types in lists (#20126)
Incorrect aggregation of empty groups after slice (#20127)
DataFrame .get_column after drop_in_place (#20120)
Subtraction with underflow on empty FixedSizeBinaryArray (#20109)
Materialize smallest dyn ints to use feature gate for i8/i16 (#20108)
Return null instead of 0. for rolling_std when window contains a single element and ddof=1 and there are nulls elsewhere in the Series (#20077)
Only slice after sort when slice is smaller than frame length (#20084)
Preserve Series name in __rpow__ operation (#20072)
Allow nested is_in() in when()/then() for full-streaming (#20052)

📖 Documentation

Add more Rust examples to User Guide (#20194)
Expand plotting docs (#19719)
Fix Rust examples in user guide (#20075)
Update by param description for rolling_*_by functions (#19715)
Correct supported compression formats (#20085)
Specify strictness in cast (#20067)

📦 Build system

Upgrade sqlparser-rs from version 0.49 to 0.52 (#20110)
Bump memmap2 to version 0.9 (#20105)
Bump object_store to version 0.11 (#20102)
Bump fs4 to version 0.12 (#20101)
Bump thiserror to version 2 (#20097)
Bump atoi_simd to version 0.16 (#20098)
Bump chrono-tz to 0.10 (#20094)
Update Rust dependency ndarray to 0.16 (#20093)
Bump Rust toolchain to nightly-2024-11-28 (#20064)

🛠️ Other improvements

Deprecate ddof parameter for correlation coefficient (#20197)
Move Bitwise aggregations to FunctionExpr (#20193)
Add ragged lines test (#20182)
Set delta version check higher (#20153)
Fix typo in assertion in datatype copy test (#20121)
Move horizontal methods to polars-ops (#20134)
Remove useless SeriesTrait::get implementations (#20136)
Add a bunch more automated row encoding sortedness tests (#20056)

Thank you to all our contributors for making this release possible! @DzenanJupic, @MarcoGorelli, @YichiZhang0613, @alexander-beedie, @coastalwhite, @dependabot, @dependabot[bot], @flowlight0, @henryharbeck, @iharthi, @ion-elgreco, @jqnatividad, @lukapeschke, @lukemanley, @mcrumiller, @nameexhaustion, @ptiza, @ritchie46, @siddharth-vi, @stijnherfst, @stinodego and @wsyxbcl