Node.js - v20.0.0

We're excited to announce the release of Node.js 20! Highlights include the new Node.js Permission Model,
a synchronous import.meta.resolve, a stable test_runner, updates of the V8 JavaScript engine to 11.3, Ada to 2.0,
and more!

As a reminder, Node.js 20 will enter long-term support (LTS) in October, but until then, it will be the "Current" release for the next six months.
We encourage you to explore the new features and benefits offered by this latest release and evaluate their potential impact on your applications.

Notable Changes

Permission Model

Node.js now has an experimental feature called the Permission Model.
It allows developers to restrict access to specific resources during program execution, such as file system operations,
child process spawning, and worker thread creation.
The API exists behind a flag --experimental-permission which when enabled will restrict access to all available permissions.
By using this feature, developers can prevent their applications from accessing or modifying sensitive data or running potentially harmful code.
More information about the Permission Model can be found in the Node.js documentation.

The Permission Model was a contribution by Rafael Gonzaga in #44004.

Custom ESM loader hooks run on dedicated thread

ESM hooks supplied via loaders (--experimental-loader=foo.mjs) now run in a dedicated thread, isolated from the main thread.
This provides a separate scope for loaders and ensures no cross-contamination between loaders and application code.

Synchronous import.meta.resolve()

In alignment with browser behavior, this function now returns synchronously.
Despite this, user loader resolve hooks can still be defined as async functions (or as sync functions, if the author prefers).
Even when there are async resolve hooks loaded, import.meta.resolve will still return synchronously for application code.

Contributed by Anna Henningsen, Antoine du Hamel, Geoffrey Booth, Guy Bedford, Jacob Smith, and Michaël Zasso in #44710

V8 11.3

The V8 engine is updated to version 11.3, which is part of Chromium 113.
This version includes three new features to the JavaScript API:

• String.prototype.isWellFormed and toWellFormed
• Methods that change Array and TypedArray by copy
• Resizable ArrayBuffer and growable SharedArrayBuffer
• RegExp v flag with set notation + properties of strings
• WebAssembly Tail Call

The V8 update was a contribution by Michaël Zasso in #47251.

Stable Test Runner

The recent update to Node.js, version 20, includes an important change to the test_runner module. The module has been marked as stable after a recent update.
Previously, the test_runner module was experimental, but this change marks it as a stable module that is ready for production use.

Contributed by Colin Ihrig in #46983

Ada 2.0

Node.js v20 comes with the latest version of the URL parser, Ada. This update brings significant performance improvements
to URL parsing, including enhancements to the url.domainToASCII and url.domainToUnicode functions in node:url.

Ada 2.0 has been integrated into the Node.js codebase, ensuring that all parts of the application can benefit from the
improved performance. Additionally, Ada 2.0 features a significant performance boost over its predecessor, Ada 1.0.4,
while also eliminating the need for the ICU requirement for URL hostname parsing.

Contributed by Yagiz Nizipli and Daniel Lemire in #47339

Preparing single executable apps now requires injecting a Blob

Building a single executable app now requires injecting a blob prepared by
Node.js from a JSON config instead of injecting the raw JS file.
This opens up the possibility of embedding multiple co-existing resources into the SEA (Single Executable Apps).

Contributed by Joyee Cheung in #47125

Web Crypto API

Web Crypto API functions' arguments are now coerced and validated as per their WebIDL definitions like in other Web Crypto API implementations.
This further improves interoperability with other implementations of Web Crypto API.

This change was made by Filip Skokan in #46067.

Official support for ARM64 Windows

Node.js now includes binaries for ARM64 Windows, allowing for native execution on the platform.
The MSI, zip/7z packages, and executable are available from the Node.js download site along with all other platforms.
The CI system was updated and all changes are now fully tested on ARM64 Windows, to prevent regressions and ensure compatibility.

ARM64 Windows was upgraded to tier 2 support by Stefan Stojanovic in #47233.

WASI version must now be specified

When new WASI() is called, the version option is now required and has no default value.
Any code that relied on the default for the version will need to be updated to request a specific version.

This change was made by Michael Dawson in #47391.

Deprecations and Removals

• [3bed5f11e0] - (SEMVER-MAJOR) url: runtime-deprecate url.parse() with invalid ports (Rich Trott) #45526

url.parse() accepts URLs with ports that are not numbers. This behavior might result in host name spoofing with unexpected input.
These URLs will throw an error in future versions of Node.js, as the WHATWG URL API does already.
Starting with Node.js 20, these URLS cause url.parse() to emit a warning.

Semver-Major Commits

• [9fafb0a090] - (SEMVER-MAJOR) async_hooks: deprecate the AsyncResource.bind asyncResource property (James M Snell) #46432
• [1948d37595] - (SEMVER-MAJOR) buffer: check INSPECT_MAX_BYTES with validateNumber (Umuoy) #46599
• [7bc0e6a4e7] - (SEMVER-MAJOR) buffer: graduate File from experimental and expose as global (Khafra) #47153
• [671ffd7825] - (SEMVER-MAJOR) buffer: use min/max of validateNumber (Deokjin Kim) #45796
• [ab1614d280] - (SEMVER-MAJOR) build: reset embedder string to "-node.0" (Michaël Zasso) #47251
• [c1bcdbcf79] - (SEMVER-MAJOR) build: warn for gcc versions earlier than 10.1 (Richard Lau) #46806
• [649f68fc1e] - (SEMVER-MAJOR) build: reset embedder string to "-node.0" (Yagiz Nizipli) #45579
• [9374700d7a] - (SEMVER-MAJOR) crypto: remove DEFAULT_ENCODING (Tobias Nießen) #47182
• [1640aeb680] - (SEMVER-MAJOR) crypto: remove obsolete SSL_OP_* constants (Tobias Nießen) #47073
• [c2e4b1fa9a] - (SEMVER-MAJOR) crypto: remove ALPN_ENABLED (Tobias Nießen) #47028
• [3ef38c4bd7] - (SEMVER-MAJOR) crypto: use WebIDL converters in WebCryptoAPI (Filip Skokan) #46067
• [08af023b1f] - (SEMVER-MAJOR) crypto: runtime deprecate replaced rsa-pss keygen parameters (Filip Skokan) #45653
• [7eb0ac3cb6] - (SEMVER-MAJOR) deps: patch V8 to support compilation on win-arm64 (Michaël Zasso) #47251
• [a7c129f286] - (SEMVER-MAJOR) deps: silence irrelevant V8 warning (Michaël Zasso) #47251
• [6f5655a18e] - (SEMVER-MAJOR) deps: always define V8_EXPORT_PRIVATE as no-op (Michaël Zasso) #47251
• [f226350fcb] - (SEMVER-MAJOR) deps: update V8 to 11.3.244.4 (Michaël Zasso) #47251
• [d6dae7420e] - (SEMVER-MAJOR) deps: V8: cherry-pick f1c888e7093e (Michaël Zasso) #45579
• [56c436533e] - (SEMVER-MAJOR) deps: fix V8 build on Windows with MSVC (Michaël Zasso) #45579
• [51ab98c71b] - (SEMVER-MAJOR) deps: silence irrelevant V8 warning (Michaël Zasso) #45579
• [9f84d3eea8] - (SEMVER-MAJOR) deps: V8: fix v8-cppgc.h for MSVC (Jiawen Geng) #45579
• [f2318cd4b5] - (SEMVER-MAJOR) deps: fix V8 build issue with inline methods (Jiawen Geng) #45579
• [16e03e7968] - (SEMVER-MAJOR) deps: update V8 to 10.9.194.4 (Yagiz Nizipli) #45579
• [6473f5e7f7] - (SEMVER-MAJOR) doc: update toolchains used for Node.js 20 releases (Richard Lau) #47352
• [cc18fd9608] - (SEMVER-MAJOR) events: refactor to use validateNumber (Deokjin Kim) #45770
• [ff92b40ffc] - (SEMVER-MAJOR) http: close the connection after sending a body without declared length (Tim Perry) #46333
• [2a29df6464] - (SEMVER-MAJOR) http: keep HTTP/1.1 conns alive even if the Connection header is removed (Tim Perry) #46331
• [391dc74a10] - (SEMVER-MAJOR) http: throw error if options of http.Server is array (Deokjin Kim) #46283
• [ed3604cd64] - (SEMVER-MAJOR) http: server check Host header, to meet RFC 7230 5.4 requirement (wwwzbwcom) #45597
• [88d71dc301] - (SEMVER-MAJOR) lib: refactor to use min/max of validateNumber (Deokjin Kim) #45772
• [e4d641f02a] - (SEMVER-MAJOR) lib: refactor to use validators in http2 (Debadree Chatterjee) #46174
• [0f3e531096] - (SEMVER-MAJOR) lib: performance improvement on readline async iterator (Thiago Oliveira Santos) #41276
• [5b5898ac86] - (SEMVER-MAJOR) lib,src: update exit codes as per todos (Debadree Chatterjee) #45841
• [55321bafd1] - (SEMVER-MAJOR) net: enable autoSelectFamily by default (Paolo Insogna) #46790
• [2d0d99733b] - (SEMVER-MAJOR) process: remove process.exit(), process.exitCode coercion to integer (Daeyeon Jeong) #43716
• [dc06df31b6] - (SEMVER-MAJOR) readline: refactor to use validateNumber (Deokjin Kim) #45801
• [295b2f3ff4] - (SEMVER-MAJOR) src: update NODE_MODULE_VERSION to 115 (Michaël Zasso) #47251
• [3803b028dd] - (SEMVER-MAJOR) src: share common code paths for SEA and embedder script (Anna Henningsen) #46825
• [e8bddac3e9] - (SEMVER-MAJOR) src: apply ABI-breaking API simplifications (Anna Henningsen) #46705
• [f84de0ad4c] - (SEMVER-MAJOR) src: use uint32_t for process initialization flags enum (Anna Henningsen) #46427
• [a6242772ec] - (SEMVER-MAJOR) src: fix ArrayBuffer::Detach deprecation (Michaël Zasso) #45579
• [dd5c39a808] - (SEMVER-MAJOR) src: update NODE_MODULE_VERSION to 112 (Yagiz Nizipli) #45579
• [63eca7fec0] - (SEMVER-MAJOR) stream: validate readable defaultEncoding (Marco Ippolito) #46430
• [9e7093f416] - (SEMVER-MAJOR) stream: validate writable defaultEncoding (Marco Ippolito) #46322
• [fb91ee4f26] - (SEMVER-MAJOR) test: make trace-gc-flag tests less strict (Yagiz Nizipli) #45579
• [eca618071e] - (SEMVER-MAJOR) test: adapt test-v8-stats for V8 update (Michaël Zasso) #45579
• [c03354d3e0] - (SEMVER-MAJOR) test: test case for multiple res.writeHead and res.getHeader (Marco Ippolito) #45508
• [c733cc0c7f] - (SEMVER-MAJOR) test_runner: mark module as stable (Colin Ihrig) #46983
• [7ce223273d] - (SEMVER-MAJOR) tools: update V8 gypfiles for 11.1 (Michaël Zasso) #47251
• [ca4bd3023e] - (SEMVER-MAJOR) tools: update V8 gypfiles for 11.0 (Michaël Zasso) #47251
• [58b06a269a] - (SEMVER-MAJOR) tools: update V8 gypfiles (Michaël Zasso) #45579
• [027841c964] - (SEMVER-MAJOR) url: use private properties for brand check (Yagiz Nizipli) #46904
• [3bed5f11e0] - (SEMVER-MAJOR) url: runtime-deprecate url.parse() with invalid ports (Rich Trott) #45526
• [7c76fddf25] - (SEMVER-MAJOR) util,doc: mark parseArgs() as stable (Colin Ihrig) #46718
• [4b52727976] - (SEMVER-MAJOR) wasi: make version non-optional (Michael Dawson) #47391

Semver-Minor Commits

• [d4b440bfac] - (SEMVER-MINOR) fs: implement byob mode for readableWebStream() (Debadree Chatterjee) #46933
• [00c222593e] - (SEMVER-MINOR) src,process: add permission model (Rafael Gonzaga) #44004
• [978b57d750] - (SEMVER-MINOR) wasi: no longer require flag to enable wasi (Michael Dawson) #47286

Semver-Patch Commits

• [e50c6b9a22] - bootstrap: do not expand process.argv[1] for snapshot entry points (Joyee Cheung) #47466
• [c81e1143e4] - bootstrap: store internal loaders in C++ via a binding (Joyee Cheung) #47215
• [8e673bdb84] - build: add node-core-utils to setup (Jiawen Geng) #47442
• [5b561d72a6] - build: sync cares source change (Jiawen Geng) #47359
• [8e6ee53e4e] - build: remove non-exist build file (Jiawen Geng) #47361
• [9a4d21d1d9] - build, deps, tools: avoid excessive LTO (Konstantin Demin) #47313
• [48c01485cd] - crypto: replace THROW with CHECK for scrypt keylen (Tobias Nießen) #47407
• [4c1a27716b] - crypto: re-add padding for AES-KW wrapped JWKs (Filip Skokan) #46563
• [b66eb15d12] - deps: update simdutf to 3.2.7 (Node.js GitHub Bot) #47473
• [3fc11477ba] - deps: update corepack to 0.17.2 (Node.js GitHub Bot) #47474
• [c1776531ab] - deps: upgrade npm to 9.6.4 (npm team) #47432
• [e7ca09f310] - deps: update zlib to upstream 5edb52d4 (Luigi Pinca) #47151
• [88387ccd12] - deps: update ada to 2.0.0 (Node.js GitHub Bot) #47339
• [9f468cc37e] - deps: cherry-pick Windows ARM64 fix for openssl (Richard Lau) #46570
• [eeab210b1b] - deps: update archs files for quictls/openssl-3.0.8+quic (RafaelGSS) #46570
• [d93d7716c7] - deps: upgrade openssl sources to quictls/openssl-3.0.8+quic (RafaelGSS) #46571
• [0f69ec4dd7] - deps: patch V8 to 10.9.194.9 (Michaël Zasso) #45995
• [5890d09644] - deps: patch V8 to 10.9.194.6 (Michaël Zasso) #45748
• [c02a7e7e93] - diagnostics_channel: fix ref counting bug when reaching zero subscribers (Stephen Belanger) #47520
• [c7ad5bb37d] - doc: info on handling unintended breaking changes (Michael Dawson) #47426
• [7d2d40ed0d] - doc: add performance initiative (Yagiz Nizipli) #47424
• [d56c0f7318] - doc: do not create a backup file (Luigi Pinca) #47151
• [412d27b65b] - doc: add MoLow to the TSC (Colin Ihrig) #47436
• [f131cca0c0] - doc: reserve 116 for Electron 25 (Keeley Hammond) #47375
• [1022c6f424] - doc: add experimental stages (Geoffrey Booth) #46100
• [42d3d74717] - doc: clarify release notes for Node.js 16.19.0 (Richard Lau) #45846
• [533c6512da] - doc: clarify release notes for Node.js 14.21.2 (Richard Lau) #45846
• [97165fc1a6] - doc: fix doc metadata for Node.js 16.19.0 (Richard Lau) #45863
• [a266b8b702] - doc: add registry number for Electron 23 & 24 (Keeley Hammond) #45661
• [2613a9ced9] - esm: move hook execution to separate thread (Jacob Smith) #44710
• [841f6b3abf] - esm: increase test coverage of edge cases (Antoine du Hamel) #47033
• [0d575fe61a] - gyp: put filenames in variables (Cheng Zhao) #46965
• [41b186722c] - lib: distinguish webidl interfaces with the extended property "Exposed" (Chengzhong Wu) #46809
• [9b7db62276] - lib: makeRequireFunction patch when experimental policy (RafaelGSS) nodejs-private/node-private#358
• [d43b532789] - lib: refactor to use validateBuffer (Deokjin Kim) #46489
• [9a76a2521b] - meta: ping security-wg team on permission model changes (Rafael Gonzaga) #47483
• [a4dadde1ba] - meta: ping startup and realm team on src/node_realm* changes (Joyee Cheung) #47448
• [631c3ef3de] - module: do less CJS module loader initialization at run time (Joyee Cheung) #47194
• [8bcf0a42f7] - permission: fix chmod,chown improve fs coverage (Rafael Gonzaga) #47529
• [54d17ff4b5] - permission: support fs.mkdtemp (Rafael Gonzaga) #47470
• [b441b5dc65] - permission: drop process.permission.deny (Rafael Gonzaga) #47335
• [aa30e16716] - permission: fix some vulnerabilities in fs (Tobias Nießen) #47091
• [1726da9300] - permission: add path separator to loader check (Rafael Gonzaga) #47030
• [b164038c86] - permission: fix spawnSync permission check (RafaelGSS) #46975
• [af91400886] - policy: makeRequireFunction on mainModule.require (RafaelGSS) nodejs-private/node-private#358
• [f8b4e26aee] - quic: add more QUIC impl (James M Snell) #47348
• [d65ae9f678] - quic: add additional quic implementation utilities (James M Snell) #47289
• [9b104be502] - quic: do not dereference shared_ptr after move (Tobias Nießen) #47294
• [09a4bb152f] - quic: add multiple internal utilities (James M Snell) #47263
• [2bde0059ca] - sea: use JSON configuration and blob content for SEA (Joyee Cheung) #47125
• [78c7475493] - src: allow simdutf::convert_* functions to return zero (Daniel Lemire) #47471
• [5250947a53] - src: track ShadowRealm native objects correctly in the heap snapshot (Joyee Cheung) #47389
• [8059764621] - src: use the internal field to determine if an object is a BaseObject (Joyee Cheung) #47217
• [698508afa8] - src: bootstrap prepare stack trace callback in shadow realm (Chengzhong Wu) #47107
• [e6b4d30a2f] - src: bootstrap Web [Exposed=*] APIs in the shadow realm (Chengzhong Wu) #46809
• [3646a66044] - src: fix AliasedBuffer memory attribution in heap snapshots (Joyee Cheung) #46817
• [8b2126f63f] - src: move AliasedBuffer implementation to -inl.h (Joyee Cheung) #46817
• [3abbc3829a] - src: fix useless call in permission.cc (Tobias Nießen) #46833
• [7b1e153530] - src: simplify exit code accesses (Daeyeon Jeong) #45125
• [7359b92a41] - test: remove unnecessary status check on test-release-npm (RafaelGSS) #47516
• [a5a5d2fb7e] - test: mark test/parallel/test-file-write-stream4 as flaky (Yagiz Nizipli) #47423
• [81ad73a205] - test: remove unused callback variables (angellovc) #47167
• [757a586ead] - test: migrate test runner message tests to snapshot (Moshe Atlow) #47392
• [86f890539f] - test: remove stale entry from known_issues.status (Richard Lau) #47454
• [1f3773d0c1] - test: move more inspector sequential tests to parallel (Joyee Cheung) #47412
• [617b8d44c6] - test: use random port in test-inspector-enabled (Joyee Cheung) #47412
• [ade0170c4f] - test: use random port in test-inspector-debug-brk-flag (Joyee Cheung) #47412
• [1a78632cd3] - test: use random port in NodeInstance.startViaSignal() (Joyee Cheung) #47412
• [23f66b137e] - test: move test-shadow-realm-gc.js to known_issues (Joyee Cheung) #47355
• [9dfd0394c5] - test: remove useless WPT init scripts (Khafra) #47221
• [1cfe058778] - test: fix test-permission-deny-fs-wildcard (win32) (Tobias Nießen) #47095
• [b8ef1b476e] - test: add coverage for custom loader hooks with permission model (Antoine du Hamel) #46977
• [4a7c3e9c50] - test: fix file path in permission symlink test (Livia Medeiros) #46859
• [10005de6a8] - tools: make js2c.py usable for other build systems (Cheng Zhao) #46930
• [1e2f9aca72] - tools: move update-acorn.sh to dep_updaters and create maintaining md (Marco Ippolito) #47382
• [174662a463] - tools: update eslint to 8.38.0 (Node.js GitHub Bot) #47475
• [a58ca61f35] - tools: update eslint to 8.38.0 (Node.js GitHub Bot) #47475
• [37d12730ab] - tools: automate cjs-module-lexer dependency update (Marco Ippolito) #47446
• [4fbfa3c9f2] - tools: fix notify-on-push Slack messages (Antoine du Hamel) #47453
• [b1f2ff1242] - tools: update lint-md-dependencies to @rollup/plugin-node-resolve\@15.0.2 (Node.js GitHub Bot) #47431
• [26b2584b84] - tools: add root certificate update script (Richard Lau) #47425
• [553b052648] - tools: remove targets for individual test suites in Makefile (Antoine du Hamel) #46892
• [747ff43e5b] - url: more sophisticated brand check for URLSearchParams (Timothy Gu) #47414
• [e727eb066f] - url: do not use object as hashmap (Timothy Gu) #47415
• [81c7875eb7] - url: drop ICU requirement for parsing hostnames (Yagiz Nizipli) #47339
• [a4895df94a] - url: use ada::url_aggregator for parsing urls (Yagiz Nizipli) #47339