2026-06-04:

- added custom malloc for small blocks (11% faster on bench-v8)
- micro optimizations (30% faster on bench-v8)
- added resizable array buffers
- added ArrayBuffer.prototype.transfer
- added the Iterator object and methods
- added set methods
- added Atomics.pause
- added added Map and WeakMap upsert methods
- added Math.sumPrecise()
- added regexp duplicate named groups
- added base64 and hexadecimal encodings for Uint8Array
- misc bug fixes

2025-09-13:

- added JSON modules and import attributes
- added JS_PrintValue() API
- qjs: pretty print objects in print() and console.log()
- qjs: better promise rejection tracker heuristics
- added RegExp v flag
- added RegExp modifiers
- added RegExp.escape
- added Float16Array
- added Promise.try
- improved JSON parser spec conformance
- qjs: improved compatibility of std.parseExtJSON() with JSON5 and
  accept JSON5 modules
- added JS_FreePropertyEnum() and JS_AtomToCStringLen() API
- added Error.isError()
- misc bug fixes

2025-04-26:

- removed the bignum extensions and qjscalc
- new BigInt implementation optimized for small numbers
- added WeakRef, FinalizationRegistry and symbols as weakrefs
- added builtin float64 printing and parsing functions for more correctness
- faster repeated string concatenation
- qjs: promise unhandled rejections are fatal errors by default
- added column number in debug information
- removed the "use strip" extension
- qjs: added -s and --strip-source options
- qjsc: added -s and --keep-source options
- added JS_GetAnyOpaque()
- added more callbacks for exotic objects in JSClassExoticMethods
- misc bug fixes

2024-01-13:

- top-level-await support in modules
- allow 'await' in the REPL
- added Array.prototype.{with,toReversed,toSpliced,toSorted} and
TypedArray.prototype.{with,toReversed,toSorted}
- added String.prototype.isWellFormed and String.prototype.toWellFormed
- added Object.groupBy and Map.groupBy
- added Promise.withResolvers
- class static block
- 'in' operator support for private fields
- optional chaining fixes
- added RegExp 'd' flag
- fixed RegExp zero length match logic
- fixed RegExp case insensitive flag
- added os.sleepAsync(), os.getpid() and os.now()
- added cosmopolitan build
- misc bug fixes

2023-12-09:

- added Object.hasOwn, {String|Array|TypedArray}.prototype.at,
  {Array|TypedArray}.prototype.findLast{Index}
- BigInt support is enabled even if CONFIG_BIGNUM disabled
- updated to Unicode 15.0.0
- misc bug fixes

2021-03-27:

- faster Array.prototype.push and Array.prototype.unshift
- added JS_UpdateStackTop()
- fixed Windows console
- misc bug fixes

2020-11-08:

- improved function parameter initializers
- added std.setenv(), std.unsetenv() and std.getenviron()
- added JS_EvalThis()
- misc bug fixes

2020-09-06:

- added logical assignment operators
- added IsHTMLDDA support
- faster for-of loops
- os.Worker now takes a module filename as parameter
- qjsc: added -D option to compile dynamically loaded modules or workers
- misc bug fixes

2020-07-05:

- modified JS_GetPrototype() to return a live value
- REPL: support unicode characters larger than 16 bits
- added os.Worker
- improved object serialization
- added std.parseExtJSON
- misc bug fixes

2020-04-12:

- added cross realm support
- added AggregateError and Promise.any
- added env, uid and gid options in os.exec()
- misc bug fixes

2020-03-16:

- reworked error handling in std and os libraries: suppressed I/O
  exceptions in std FILE functions and return a positive errno value
  when it is explicit
- output exception messages to stderr
- added std.loadFile(), std.strerror(), std.FILE.prototype.tello()
- added JS_GetRuntimeOpaque(), JS_SetRuntimeOpaque(), JS_NewUint32()
- updated to Unicode 13.0.0
- misc bug fixes

2020-01-19:

- keep CONFIG_BIGNUM in the makefile
- added os.chdir()
- qjs: added -I option
- more memory checks in the bignum operations
- modified operator overloading semantics to be closer to the TC39
  proposal
- suppressed "use bigint" mode. Simplified "use math" mode
- BigDecimal: changed suffix from 'd' to 'm'
- misc bug fixes

2020-01-05:

- always compile the bignum code. Added '--bignum' option to qjs.
- added BigDecimal
- added String.prototype.replaceAll
- misc bug fixes

2019-12-21:

- added nullish coalescing operator (ES2020)
- added optional chaining (ES2020)
- removed recursions in garbage collector
- test stack overflow in the parser
- improved backtrace logic
- added JS_SetHostPromiseRejectionTracker()
- allow exotic constructors
- improved c++ compatibility
- misc bug fixes

2019-10-27:

- added example of C class in a module (examples/test_point.js)
- added JS_GetTypedArrayBuffer()
- misc bug fixes

2019-09-18:

- added os.exec and other system calls
- exported JS_ValueToAtom()
- qjsc: added 'qjsc_' prefix to the generated C identifiers
- added cross-compilation support
- misc bug fixes

2019-09-01:

- added globalThis
- documented JS_EVAL_FLAG_COMPILE_ONLY
- added import.meta.url and import.meta.main
- added 'debugger' statement
- misc bug fixes

2019-08-18:

- added os.realpath, os.getcwd, os.mkdir, os.stat, os.lstat,
  os.readlink, os.readdir, os.utimes, std.popen
- module autodetection
- added import.meta
- misc bug fixes

2019-08-10:

- added public class fields and private class fields, methods and
  accessors (TC39 proposal)
- changed JS_ToCStringLen() prototype
- qjsc: handle '-' in module names and modules with the same filename
- added std.urlGet
- exported JS_GetOwnPropertyNames() and JS_GetOwnProperty()
- exported some bigint C functions
- added support for eshost in run-test262
- misc bug fixes

2019-07-28:

- added dynamic import
- added Promise.allSettled
- added String.prototype.matchAll
- added Object.fromEntries
- reduced number of ticks in await
- added BigInt support in Atomics
- exported JS_NewPromiseCapability()
- misc async function and async generator fixes
- enabled hashbang support by default

2019-07-21:

- updated test262 tests
- updated to Unicode version 12.1.0
- fixed missing Date object in qjsc
- fixed multi-context creation
- misc ES2020 related fixes
- simplified power and division operators in bignum extension
- fixed several crash conditions

2019-07-09:

- first public release
