chore(main): release 1.21.0

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🤖 I have created a release beep boop

1.21.0 (2026-08-29)

Features

• add credit card schema validator (6588a67)
• add credit card schema validator (3a718b6)
• add map values cleaning step (5fc60ab)
• add map values cleaning step (61c9879)
• add native UUID and IPAddress schema field validators (#2117) (a01a1cd)
• add native UUID and IPAddress schema field validators (#2117) (1061608)
• add native UUID and IPAddress schema field validators (#2117) (c3353c9)
• add native UUID and IPAddress schema field validators (#2117) (5f0f164)
• add per-column memory usage (cf527a0)
• add per-column memory usage (2156207)
• add profile CLI command (b54a185)
• add profile CLI command (af44a84)

Bug Fixes

• add case sensitivity to semantic factories (e71b454)
• add case sensitivity to semantic factories (6aee649)
• avoid deprecated coalesce bfill axis (d874761)
• avoid deprecated coalesce bfill axis (69c298f)
• block remote CSV redirects (06dff89)
• block remote CSV redirects (3cea713)
• cpp: declare CsvChunkReader methods in header and fix scan_schema member accesses (875c378)
• cpp: fix CsvReader::parse_value scope and Frame constructor calls (555c9ec)
• cpp: remove corrupt read loop duplicating PASS 1 logic in csv_reader.cpp (82c467b)
• cpp: remove stray duplicated closing block in csv_reader.cpp (6ed0a0e)
• cpp: resolve compilation syntax errors in frame.h and cleaning.cpp (92147bf)
• preserve safe_divide_columns attrs (669c4e9)
• preserve safe_divide_columns attrs (c37dcf4)
• reduce hero vertical whitespace (8d4da3e)
• reduce hero vertical whitespace (4aa5544)
• skip winsorize no-op conversion (726e98c)
• skip winsorize no-op conversion (a9bdacd)
• write json outputs atomically (81cbbab)
• write json outputs atomically (561e588)

Performance Improvements

• reserve column capacity from row count (#257) (600e9c3)
• reserve column capacity from row count (#257) (861c2f5)

Documentation

• add benchmark quick start (4ace8a5)
• add benchmark quick start (d60f506)
• API reference documents unsupported read_csv mode="lax" (#2396) (378e018)
• API reference documents unsupported read_csv mode="lax" (#2396) (ae213df)
• indent code blocks in interoperability examples list (6ee02a1)
• indent code blocks in interoperability examples list (6a5eca4)
• keep check_env example dashboard in sync with examples directory (#1400) (d68fc51)
• normalize API_REFERENCE.md to valid UTF-8 (#1386) (f1c8ea2)
• null_values pages incorrectly describe custom tokens as additive (#2447) (aa76b7c)
• null_values pages incorrectly describe custom tokens as additive (#2447) (311d6dc)
• sync website release metadata (8d5a1d8)
• sync website release metadata (58573d7)

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Project	Deployment	Actions	Updated (UTC)
arnio	Ready	Preview	Aug 29, 2026 9:55pm