$ git clone git://github.com/spencertipping/ni && cd ni
$ ./ni --help                   # start here
$ ./ni --js                     # ...or here if you like to live on the edge

Some places to start reading:

• The Docs: really smashing documentation
• Ni by Example: a tutorial that won't say "ni" to you
• The Cheatsheet: a tutorial that will say "ni" to you
• Web UI Examples: straight into the deep end with the web UI

...in the last decade, except Windows. Its only dependency is Perl 5.8 or later, which is installed basically everywhere (and in any context involving remote jobs, like hadoop, SSH, docker, etc, ni automatically installs itself so you don't have to do any configuration).

$ git clone git://github.com/spencertipping/ni
$ ln -s $PWD/ni/ni ~/bin/               # if ~/bin is on your $PATH
$ sudo ln -s $PWD/ni/ni /usr/bin/       # system-wide installation

• Factual, Inc
• Joyce Tipping
• Michael Bilow
• Spencer Tipping
• Wes Henderson

(Also included in the top of the ni image, and available by running ni //license.)

Copyright (c) 2016 Spencer Tipping

MIT license

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

$ ./test                        # accurate but time-consuming; see below

./test automatically rebuilds your ./ni image from source.

If you've just made a small change and don't want to wait the full ten minutes it takes to run all tests on all distributions, here's a lighter-weight way to do it:

$ ./test --build                # if you're testing for the first time
$ ./test --quick centos-5       # faster than running all tests
$ ./test --quick ubuntu-16.04   # includes hadoop/spark/docker tests

• ./boot: create the base ni image with no extensions. This image does almost nothing and is effectively unusable.
• bugs/: documentation and tests for all nontrivial bugs I've found, starting 2016.0918.
• ./build: run ./boot, then extend with a bunch of libraries. See the dev docs for information about how this works.
• core/: all of the core libraries installed by ./build onto the base image (which itself is built from core/boot).
• dev/: documentation and scripts for ni development.
• doc/: documentation for using ni. This ends up being added to the ni image by ./build. Examples in the documentation are extracted into tests by ./lazytest. (Warning: Turn off your editor's whitespace features if you edit doc/; test outputs are verified at the byte level, including tabs and trailing whitespace in some cases.)
• env/: dockerfiles for ni portability testing. This way we can make sure it works with new and old versions of Perl and coreutils. ./test builds and runs these.
• ./lazytest: a copy of LazyTest used to generate unit tests from the documentation examples. This is run by ./test.
• ./ni: the fully-built ni image if you run ./build, or just the core image if you run ./boot. The version checked into the repo should always be a full build.
• ./test: runs unit tests or launches a test environment. All tests are run inside one of the dockerized environments; see the dev docs for more details about how this works.