improve reducing window function performance ~33% (#5878)
impove performance reducing window functions with numeric output ~-14% (#5841)
set_sorted flag when creating from literal (#5728)
use sorted fast path in streaming groupby (#5727)
ensure fast_explode propagates (#5676)
fix quadratic time complexity of groupby in stream… (#5614)
Aggregate projection pushdown (#5556)
improve streaming primitve groupby (#5575)
vectorize integer vec-hash by using very simple, … (#5572)
specialized utf8 groupby in streaming (#5535)

✨ Enhancements

make get_any_value fallible (#5877)
directly push all operator result into sink, prev… (#5856)
add sink_parquet (#5480)
Support parsing more float string representations. (#5824)
implement mean aggregation for duration (#5807)
implement sensible boolean aggregates (#5806)
allow expression as quantile input (#5751)
accept expression in str.extract_all (#5742)
tz-aware strptime (#5736)
Add "fmt_no_tty" feature for formatting support without r… (#5725)
lazy diagonal concat. (#5647)
to_struct add upper_bound (#5714)
inversely scale chunk_size with thread count in s… (#5699)
add streaming minmax (#5693)
improve dynamic inference of anyvalues and structs (#5690)
support is_in for boolean dtype (#5682)
add a cache to strptime (#5628)
add nearest interpolation strategy (#5626)
make cast recursive (#5596)
add arg_min/arg_max for series of dtype boolean (#5592)
prefer streaming groupby if partitionable (#5580)
make map_alias fallible (#5532)
pl.min & pl.max accept wildcard similar to pl.sum (#5511)
add predicate pushdown to anonymous_scan (#5467)
make streaming work with multiple sinks in a sing… (#5474)
add streaming slice operation (#5466)
run partial streaming queries (#5464)
streaming left joins (#5456)
file statistics so we only (try to) keep smallest table in memory (#5454)
streaming inner joins. (#5400)
build_info() provides detailed information how polars was built (#5423)
add missing width property to LazyFrame (#5431)
allow regex and wildcard in groupby (#5425)
Streaming joins architecture and Cross join implementation. (#5339)
add support for am/pm notation in parse_dates read_csv (#5373)
add reduce/cumreduce expression as an easier fold (#5364)

🐞 Bug fixes

fix lazy swapping rename (#5884)
improve equality consistency between types (#5873)
evaluate whole branch expression to determine if r… (#5864)
fix top_k on empty (#5865)
fix slice in streaming (#5854)
correct invalid type in struct anyvalue access (#5844)
don't set fast_explode if null values in list (#5838)
duration formatting (#5837)
respect fetch in union (#5836)
keep f32 dtype in fill_null by int (#5834)
err on epoch on time dtype (#5831)
fix panic in hmean (#5808)
asof join by logical groups (#5805)
fix parquet regression upstream in arrow2 (#5797)
Fix lazy cumsum and cumprod result types (#5792)
fix nested writer (#5777)
fix(rust, python) Summation on empty series evaluates to Some(0) (#5773)
empty concat utf8 (#5768)
projection pushdown with union and asof join (#5763)
check null values in asof_join + groupby (#5756)
fix generic streaming groupby on logical types (#5752)
fix date_range on expressions (#5750)
fix dtypes in join_asof_by (#5746)
fix group order in binary aggregation (#5744)
implement min/max aggregation for utf8 in groupby (#5737)
fix all_null/sorted into_groups panic (#5733)
asof join 'by', 'forward' combination (#5720)
fix pivot on floating point indexes (#5704)
fix arange with column/literal input (#5703)
fix double projection that leads to uneven union d… (#5700)
Fix a bug in floating regex handling used in CSV type inference (#5695)
fix asof join schema (#5686)
fix owned arithmetic schema (#5685)
take glob into account in scan_csv 'with_schema_mo… (#5683)
fix boolean schema in agg_max/min (#5678)
fix boolean arg-max if all equal (#5680)
early error on duplicate names in streaming groupby (#5638)
fix streaming groupby aggregate types (#5636)
convert panic to err in concat_list (#5637)
fix dot diagram of single nodes (#5624)
fix dynamic struct inference (#5619)
keep dtype when eval on empty list (#5597)
fix ternary with list output on empty frame (#5595)
fix tz-awareness of truncate (#5591)
check chunks before doing chunked_id join optimiza… (#5589)
invert cast_time_zone conversion (#5587)
asof join ensure join column is not dropped when '… (#5585)
fix ub due to invalid dtype on splitting dfs (#5579)
fix(rust, python); fix projection pushdown in asof joins (#5542)
streaming hstack allow duplicates (#5538)
fix streaming empty join panic (#5534)
fix duplicate caches in cse and prevent quadratic … (#5528)
allow appending categoricals that are all null (#5526)
tz-aware strftime (#5525)
make 'truncate' tz-aware (#5522)
fix coalesce expreession expansion (#5521)
fix nested aggregatin in when then and window expr… (#5520)
fix sort_by expression if groups already aggregated (#5518)
fix bug in batched parquet reader that dropped dfs… (#5506)
fix bugs in skew and kurtosis (#5484)
compute correct offset for streaming join on multi… (#5479)
return error on invalid sortby expression (#5478)
add missing AnyValueBuffer specialisation for Duration dtype (#5436)
fix freeze/stall when writing more than 2^31 string values to parquet (#5366)
properly handle json with unclosed strings (#5427)
fix null poisoning in rank operation (#5417)
correct expr::diff dtype for temporal columns (#5416)
fix cse for nested caches (#5412)
don't set sorted flag in argsort (#5410)
explicit nan comparison in min/max agg (#5403)
Correct CSV row indexing (#5385)

🛠️ Other improvements

Update rustc and fix clippy (#5880)
update arrow (#5862)
move join dispatch to polars-ops (#5809)
Remove dbg statement from union (#5791)
Continue removing compilation warnings (#5778)
shrink anyvalue size (#5770)
update arrow (#5766)
chore(rust,python) Change allow_streaming to streaming (#5747)
remove rev-map from ChunkedArray (#5721)
simplify fast projection by schema (#5716)
Reindent df! docs code (#5698)
remove Series::append_array (#5681)
Remove unused symbols and uneeded mut qualifier (#5672)
Include license files in Rust crates (#5675)
Use NaiveTime::from_hms_opt instead of NaiveTime::from_hms (#5664)
use xxhash3 for string types (#5617)
iso weekday (#5598)
Improve contributing guide (#5558)
streaming improvements (#5541)
Refer to DataFrame::unique instead of distinct (#5482)
don't panic if part of query cannot run strea… (#5458)
make generic join builder more dry (#5439)
use IdHash for streaming groupby generic (#5435)
fix freeze/stall when writing more than 2^31 string values to parquet (#5366)

Thank you to all our contributors for making this release possible! @AnatolyBuga, @CalOmnie, @Kuhlwein, @MarcoGorelli, @OneRaynyDay, @YuRiTan, @alexander-beedie, @andrewpollack, @ankane, @braaannigan, @chitralverma, @dannyvankooten, @ghais, @ghuls, @jjerphan, @matteosantama, @messense, @owrior, @pickfire, @ritchie46, @s1ck, @sa-, @slonik-az, @sorhawell, @stinodego, @universalmind303 and @zundertj