propagate null in equality comparisons (#9053)
formalize implode -> explode relation (#9038)
consistently return list of date/datetime from lazy date_range (#8513)
Rename list namespace accesor from .arr to .list (#8999)
disallow time zones other than those in zoneinfo.available_timezones() (#8993)
remove window expression magic (#8992)
raise error when sorted flag not set (#8994)
in Series constructor, if inputs are time-zone-aware datetimes, convert to UTC (#8881)
parse offset-naive date time strings as Timestamp(time_unit), offset-aware datetime strings as Timestamp(time_unit, "UTC"), and remove the utc argument (#8714)
Remove deprecated tz_aware argument (#8696)

🚀 Performance improvements

speed up write_csv for time-zone-aware columns (#9093)
parallelize rolling_window group materialization (#9095)
elide hot loop in hash joins (#9075)
improve list explode perf (#8974)
Improve explodes: offsets_to_indexes performance (#8964)
avoid quadratic exclude behaviour when selecting against dtypes and/or wildcards (#8953)
use simd-json for all json parsing (#8922)
improve json_extract (#8858)
add optimizer passes and change initial order (#8811)
fused multiply sub / sub multiply (#8799)
improve parallel work distribution of sort expression ~4x (#8775)
change default row-group size (#8758)

✨ Enhancements

conversion from Utf8 to Decimal. (#9090)
default to checking sortedness in groupby_rolling… (#9063)
propagate null in equality comparisons (#9053)
implement apply for rolling/dynamic_groupby (#9049)
implement strategy=nearest for join_asof (#9024)
arr.sum expression (#9041)
formalize implode -> explode relation (#9038)
add array namespace and min/max expression (#9032)
improve error message on row-wise overflow (#9021)
properly apply slice at UNION level (#9018)
consistently return list of date/datetime from lazy date_range (#8513)
disallow time zones other than those in zoneinfo.available_timezones() (#8993)
raise error when sorted flag not set (#8994)
in Series constructor, if inputs are time-zone-aware datetimes, convert to UTC (#8881)
parse offset-naive date time strings as Timestamp(time_unit), offset-aware datetime strings as Timestamp(time_unit, "UTC"), and remove the utc argument (#8714)
error on invalid sortby expr (#8986)
Pushdown is_in to pyarrow dataset (#8930)
Array (backed by arrow::FixedSizeList datatype (#8943)
multiple enhancements for SQLContext (#8944)
add sql UNION, UNION ALL & UNION DISTINCT (#8936)
add sql compound identifiers (#8934)
add sql EXCLUDE (#8913)
add sql CASE (#8911)
add sql EXPLAIN (#8897)
improve json_extract (#8858)
add support for sql DISTINCT ON (#8824)
add LazyFrame null_count (#8837)
check categorical cache on transpose (#8836)
add support for OFFSET keyword in SQL queries (#8833)
add a new time_range utility function (#8776)
Add hint to use _saturating on overflow (#8805)
support boolean addition (#8778)
improved detail in several error messages (#8747)

🐞 Bug fixes

rolling_groupy was returning incorrect results when offset was positive (#9082)
fix null/empty in List::take_unchecked (#9074)
repeat by (#9023)
raise in to_datetime/strptime if format contains hour but not minute directive (#9044)
propagate nulls in broadcasting of order comparisons (#9050)
fix apply with passed date/datetime return_dtype (#9035)
raise error on invalid aggregation (#9013)
fix fused arithmetic in window functions (#9012)
JoinBuilder::force_parallel is modifying allow_parallel (#8617)
Fix erroneous warning in hist (#8982)
respect rechunk in parquet (#8935)
Simplify offsets_to_indexes, fix empty offsets edge cases (#8920)
sql qualified wildcards (#8916)
don't check sortedness in asof by (#8906)
check for object type in csv writer (#8894)
window function with filtered groups (#8880)
parse offset-aware strings as UTC in read_csv when try_parse_dates=True (#8864)
free buffer, but not its contents (#8848)
improve agg expr field types (#8834)
sql BETWEEN bounds should be inclusive (#8818)
sort cached window groups (#8813)
check null data before take (#8812)
fix broadcasting on integer bitwise (#8798)
correct aggregation of overlapping groups (#8794)
modify join error (#8768)
don't parallelize sort within rayon job (#8774)
fix deadlock in cache and improve parallelism/work… (#8765)
check offset before doing owned mutation (#8760)
validate data on successful deserialization (#8757)
improve supertype coercion of functions (#8755)

🛠️ Other improvements

use concrete type for time zones (#9076)
factor add_month out of add_impl_month_week_or_day (#9066)
remove unnecessary timezone trait usage, use concrete type (#9065)
Fix broken links (#9072)
bump sqlparser version (#9043)
move list namespace functions to seperate module (#9040)
Clean up arange/date_range/time_range (#9027)
Rename list namespace accesor from .arr to .list (#8999)
replace pattern match with unwrap (#9000)
remove window expression magic (#8992)
Remove deprecated tz_aware argument (#8696)
simplify take_every (#8971)
add readmes to all sub crates (#8770)
refactor(rust); improve arithmetic reuse and don't allocate on binary… (#8781)
accumulate windows flag during translation (#8773)

Thank you to all our contributors for making this release possible! @CloseChoice, @MarcoGorelli, @alexander-beedie, @avimallu, @cbowdon, @charliegallop, @chitralverma, @jonashaag, @kpberry, @mcrumiller, @petar-savov, @raymead, @ritchie46, @sorhawell, @stinodego, @tim-habitat, @uchiiii and @universalmind303