3.3.1 • Public • Published


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This repository began as a GitHub fork of joyent/node.

io.js contributions, releases, and contributorship are under an open governance model. We intend to land, with increasing regularity, releases which are compatible with the npm ecosystem that has been built to date for Node.js.

Is it io.js or IO.js or iojs or IOjs or iOjS?

The official name is io.js, which should never be capitalized, especially not at the start of a sentence, unless it is being displayed in a location that is customarily all-caps (such as the title of man pages).


Binaries, installers, and source tarballs are available at

Releases are available at, listed under their version string. The symlink will point to the latest release directory.

Nightly builds are available at, listed under their version string which includes their date (in UTC time) and the commit SHA at the HEAD of the release.

API documentation is available in each release and nightly directory under docs. points to the latest version.

Verifying Binaries

Release and nightly download directories all contain a SHASUM256.txt file that lists the SHA checksums for each file available for download. To check that a downloaded file matches the checksum, run it through sha256sum with a command such as:

$ grep iojs-vx.y.z.tar.gz SHASUMS256.txt | sha256sum -c -

(Where "iojs-vx.y.z.tar.gz" is the name of the file you have downloaded)

Additionally, releases (not nightlies) have GPG signed copies of SHASUM256.txt files available as SHASUM256.txt.asc. You can use gpg to verify that the file has not been tampered with.

To verify a SHASUM256.txt.asc, you will first need to import all of the GPG keys of individuals authorized to create releases. They are listed at the bottom of this README under Release Team. Use a command such as this to import the keys:

$ gpg --keyserver \
  --recv-keys DD8F2338BAE7501E3DD5AC78C273792F7D83545D

(See the bottom of this README for a full script to import active release keys)

You can then use gpg --verify SHASUMS256.txt.asc to verify that the file has been signed by an authorized member of the io.js team.

Once verified, use the SHASUMS256.txt.asc file to get the checksum for the binary verification command above.


Unix / Macintosh


  • gcc and g++ 4.8 or newer, or
  • clang and clang++ 3.4 or newer
  • Python 2.6 or 2.7
  • GNU Make 3.81 or newer
  • libexecinfo (FreeBSD and OpenBSD only)
$ ./configure
$ make
$ [sudo] make install

If your Python binary is in a non-standard location or has a non-standard name, run the following instead:

$ export PYTHON=/path/to/python
$ $PYTHON ./configure
$ make
$ [sudo] make install

To run the tests:

$ make test

To build the documentation:

$ make doc

To read the documentation:

$ man doc/iojs.1

To test if io.js was built correctly:

$ iojs -e "console.log('Hello from io.js ' + process.version)"



  • Python 2.6 or 2.7
  • Visual Studio 2013 for Windows Desktop, or
  • Visual Studio Express 2013 for Windows Desktop
  • Basic Unix tools required for some tests, Git for Windows includes Git Bash and tools which can be included in the global PATH.
> vcbuild nosign

To run the tests:

> vcbuild test

To test if io.js was built correctly:

$ iojs -e "console.log('Hello from io.js ' + process.version)"

Android / Android based devices, aka. Firefox OS

Be sure you have downloaded and extracted [Android NDK] ( before in a folder. Then run:

$ ./android-configure /path/to/your/android-ndk
$ make

Intl (ECMA-402) support:

Intl support is not enabled by default.

"small" (English only) support

This option will build with "small" (English only) support, but the full Intl (ECMA-402) APIs. With --download=all it will download the ICU library as needed.

Unix / Macintosh:

$ ./configure --with-intl=small-icu --download=all


> vcbuild small-icu download-all

The small-icu mode builds with English-only data. You can add full data at runtime.

Note: more docs are on the joyent/node wiki.

Build with full ICU support (all locales supported by ICU):

With the --download=all, this may download ICU if you don't have an ICU in deps/icu.

Unix / Macintosh:

$ ./configure --with-intl=full-icu --download=all


> vcbuild full-icu download-all

Build with no Intl support :-(

The Intl object will not be available. This is the default at present, so this option is not normally needed.

Unix / Macintosh:

$ ./configure --with-intl=none


> vcbuild intl-none

Use existing installed ICU (Unix / Macintosh only):

$ pkg-config --modversion icu-i18n && ./configure --with-intl=system-icu

Build with a specific ICU:

You can find other ICU releases at the ICU homepage. Download the file named something like icu4c-**##.#**-src.tgz (or .zip).

Unix / Macintosh

# from an already-unpacked ICU:
$ ./configure --with-intl=[small-icu,full-icu] --with-icu-source=/path/to/icu

# from a local ICU tarball
$ ./configure --with-intl=[small-icu,full-icu] --with-icu-source=/path/to/icu.tgz

# from a tarball URL
$ ./configure --with-intl=full-icu --with-icu-source=http://url/to/icu.tgz


First unpack latest ICU to deps/icu icu4c-##.#-src.tgz (or .zip) as deps/icu (You'll have: deps/icu/source/...)

> vcbuild full-icu

Building io.js with FIPS-compliant OpenSSL

NOTE: Windows is not yet supported

It is possible to build io.js with OpenSSL FIPS module.

Note that building in this way does not allow you to claim that the runtime is FIPS 140-2 validated. Instead you can indicate that the runtime uses a validated module. See the [security policy] ( page 60 for more details. In addition, the validation for the underlying module is only valid if it is deployed in accordance with its [security policy] ( If you need FIPS validated cryptography it is recommended that you read both the [security policy] ( and [user guide] (


  1. Obtain a copy of openssl-fips-x.x.x.tar.gz. To comply with the security policy you must ensure the path through which you get the file complies with the requirements for a "secure installation" as described in section 6.6 in the [user guide] ( For evaluation/experimentation you can simply download and verify openssl-fips-x.x.x.tar.gz from
  2. Extract source to openssl-fips folder and cd openssl-fips
  3. ./config
  4. make
  5. make install (NOTE: to comply with the security policy you must use the exact commands in steps 3-5 without any additional options as per Appendix A in the [security policy] ( The only exception is that ./config no-asm can be used in place of ./config )
  6. Get into io.js checkout folder
  7. ./configure --openssl-fips=/path/to/openssl-fips/installdir For example on ubuntu 12 the installation directory was /usr/local/ssl/fips-2.0
  8. Build io.js with make -j
  9. Verify with node -p "process.versions.openssl" (1.0.2a-fips)

Resources for Newcomers


All security bugs in io.js are taken seriously and should be reported by emailing This will be delivered to a subset of the project team who handle security issues. Please don't disclose security bugs public until they have been handled by the security team.

Your email will be acknowledged within 24 hours, and you’ll receive a more detailed response to your email within 48 hours indicating the next steps in handling your report.

Current Project Team Members

The io.js project team comprises a group of core collaborators and a sub-group that forms the Technical Steering Committee (TSC) which governs the project. For more information about the governance of the io.js project, see

TSC (Technical Steering Committee)


Collaborators & TSC members follow the in maintaining the io.js project.

Release Team

Releases of Node.js and io.js will be signed with one of the following GPG keys:

The full set of trusted release keys can be imported by running:

gpg --keyserver --recv-keys 9554F04D7259F04124DE6B476D5A82AC7E37093B
gpg --keyserver --recv-keys 94AE36675C464D64BAFA68DD7434390BDBE9B9C5
gpg --keyserver --recv-keys 0034A06D9D9B0064CE8ADF6BF1747F4AD2306D93
gpg --keyserver --recv-keys FD3A5288F042B6850C66B31F09FE44734EB7990E
gpg --keyserver --recv-keys 71DCFD284A79C3B38668286BC97EC7A07EDE3FC1
gpg --keyserver --recv-keys DD8F2338BAE7501E3DD5AC78C273792F7D83545D

See the section above on Verifying Binaries for details on what to do with these keys to verify that a downloaded file is official.

Previous releases of Node.js have been signed with one of the following GPG keys:

  • Julien Gilli <> 114F43EE0176B71C7BC219DD50A3051F888C628D
  • Timothy J Fontaine <> 7937DFD2AB06298B2293C3187D33FF9D0246406D
  • Isaac Z. Schlueter <> 93C7E9E91B49E432C2F75674B0A78B0A6C481CF6

b6a4c05... doc: reorg release team to separate section




npm i iojs-linux-arm64

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