Issues

• (this as Writable<this>).field = ... no longer works in 5.9.0

  bug
  sindresorhus/type-fest#1515 · Filter by author DayKev opened on Sep 4, 2026

• bug: Replace<> (when ${number} is Search)

  bug
  sindresorhus/type-fest#1506 · Filter by author salisbury-espinosa opened on Aug 18, 2026

• bug: constraint on PathUnion in PickDeep

  bug
  sindresorhus/type-fest#1502 · Filter by author salisbury-espinosa opened on Aug 15, 2026

• ConditionalPick and ConditionalKeys break on types with index signatures

  bug
  sindresorhus/type-fest#1501 · Filter by author ettmetal opened on Aug 15, 2026

• bug: Get<> ==> unknown

  bug
  sindresorhus/type-fest#1499 · Filter by author salisbury-espinosa opened on Aug 14, 2026
  1

• SetRequired should remove 'undefined' from the possible value

  enhancement
  sindresorhus/type-fest#1467 · Filter by author IlyaSemenov opened on Jun 29, 2026
  5

• Proposal: Type Trimming for Tuples

  type addition
  sindresorhus/type-fest#1444 · Filter by author airismadeupofair opened on Jun 2, 2026
  4

• Bug: IsEqual<100, 100n> is False

  bug
  sindresorhus/type-fest#1442 · Filter by author Emiyaaaaa opened on Jun 1, 2026
  6

• Proposal: RequiredExcept<T, Keys> and OptionalExcept<T, Keys>

  enhancement
  sindresorhus/type-fest#1427 · Filter by author ManorSailor opened on May 16, 2026
  2

• OmitOptional and OmitOptionalDeep: Removes non-required keys from an object.

  type addition
  sindresorhus/type-fest#1426 · Filter by author cprecioso opened on May 15, 2026
  3

  

• Except not playing well conditional types and/or infer

  bug
  sindresorhus/type-fest#1421 · Filter by author gt-hive-benedict-lee opened on May 12, 2026
  1

• Numeric comparison types: support for bigints?

  enhancement
  sindresorhus/type-fest#1413 · Filter by author ajvincent opened on Apr 30, 2026
  

• Proposal: NarrowBy<T, Filters extends { [K in Paths<T>]?: any }>

  type addition
  sindresorhus/type-fest#1397 · Filter by author salisbury-espinosa opened on Apr 3, 2026
  1

• possible bug in ConditionalPickDeep (enum case)

  bug
  sindresorhus/type-fest#1389 · Filter by author salisbury-espinosa opened on Mar 21, 2026
  1

• options to conditional-keys

  type addition
  sindresorhus/type-fest#1385 · Filter by author salisbury-espinosa opened on Mar 19, 2026
  2

• We may need to allocate a separate package for custom eslint rule lint-rules/validate-jsdoc-codeblocks.js

  type addition
  sindresorhus/type-fest#1384 · Filter by author salisbury-espinosa opened on Mar 18, 2026
  3

• type-fest / ts-extras eslint plugin released.

  meta
  sindresorhus/type-fest#1382 · Filter by author Nick2bad4u opened on Mar 17, 2026
  1

• Get incorrect behavior

  bug
  sindresorhus/type-fest#1372 · Filter by author salisbury-espinosa opened on Feb 21, 2026
  1

• Suggestions: Extends<T, U>, Not<T>, IsExactType<T, U>

  type addition
  sindresorhus/type-fest#1371 · Filter by author ghost opened on Feb 19, 2026
  7

• Merge broken after upgrade to 5.4.2

  bug
  sindresorhus/type-fest#1342 · Filter by author strblr opened on Jan 28, 2026
  6

• HasRequiredKeys discussion

  bugenhancement
  sindresorhus/type-fest#1334 · Filter by author ghost opened on Jan 26, 2026
  18

• Proposal: ConditionalPaths

  type addition
  sindresorhus/type-fest#1328 · Filter by author bvandrc opened on Jan 20, 2026
  1

• ArraySlice should wrap around for -T['length'] < Start/End < 0

  enhancement
  sindresorhus/type-fest#1325 · Filter by author Bertie690 opened on Jan 3, 2026

• DeepValuesOf

  type addition
  sindresorhus/type-fest#1315 · Filter by author bvandrc opened on Dec 18, 2025

• HasNonNullish?

  type addition
  sindresorhus/type-fest#1311 · Filter by author stevenvachon opened on Dec 9, 2025
  1