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+[![Actions Status: macOS](https://github.com/ruby/ruby/workflows/macOS/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"macOS")
+[![Actions Status: MinGW](https://github.com/ruby/ruby/workflows/MinGW/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MinGW")
+[![Actions Status: MJIT](https://github.com/ruby/ruby/workflows/MJIT/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MJIT")
+[![Actions Status: Ubuntu](https://github.com/ruby/ruby/workflows/Ubuntu/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Ubuntu")
+[![Actions Status: Windows](https://github.com/ruby/ruby/workflows/Windows/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Windows")
+[![AppVeyor status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/master?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/master)
+[![Travis Status](https://app.travis-ci.com/ruby/ruby.svg?branch=master)](https://app.travis-ci.com/ruby/ruby)
+[![Cirrus Status](https://api.cirrus-ci.com/github/ruby/ruby.svg)](https://cirrus-ci.com/github/ruby/ruby/master)
+
+# What's Ruby
+
+Ruby is an interpreted object-oriented programming language often
+used for web development. It also offers many scripting features
+to process plain text and serialized files, or manage system tasks.
+It is simple, straightforward, and extensible.
+
+## Features of Ruby
+
+*   Simple Syntax
+*   **Normal** Object-oriented Features (e.g. class, method calls)
+*   **Advanced** Object-oriented Features (e.g. mix-in, singleton-method)
+*   Operator Overloading
+*   Exception Handling
+*   Iterators and Closures
+*   Garbage Collection
+*   Dynamic Loading of Object Files (on some architectures)
+*   Highly Portable (works on many Unix-like/POSIX compatible platforms as
+    well as Windows, macOS, etc.) cf.
+    https://github.com/ruby/ruby/blob/master/doc/contributing.rdoc#label-Platform+Maintainers
+
+
+## How to get Ruby
+
+For a complete list of ways to install Ruby, including using third-party tools
+like rvm, see:
+
+https://www.ruby-lang.org/en/downloads/
+
+### Git
+
+The mirror of the Ruby source tree can be checked out with the following command:
+
+    $ git clone https://github.com/ruby/ruby.git
+
+There are some other branches under development. Try the following command
+to see the list of branches:
+
+    $ git ls-remote https://github.com/ruby/ruby.git
+
+You may also want to use https://git.ruby-lang.org/ruby.git (actual master of Ruby source)
+if you are a committer.
+
+### Subversion
+
+Stable branches for older Ruby versions can be checked out with also the
+following command:
+
+    $ svn co https://svn.ruby-lang.org/repos/ruby/branches/ruby_2_6/ ruby
+
+Try the following command to see the list of branches:
+
+    $ svn ls https://svn.ruby-lang.org/repos/ruby/branches/
+
+
+## Ruby home page
+
+https://www.ruby-lang.org/
+
+## Mailing list
+
+There is a mailing list to discuss Ruby. To subscribe to this list, please
+send the following phrase:
+
+    subscribe
+
+in the mail body (not subject) to the address [ruby-talk-request@ruby-lang.org].
+
+[ruby-talk-request@ruby-lang.org]: mailto:ruby-talk-request@ruby-lang.org?subject=Join%20Ruby%20Mailing%20List&body=subscribe
+
+## Requirements to build from repository
+
+1. GNU or BSD make
+2. C99 compiler
+3. autoconf 2.67 or higher
+4. automake 1.15 or higher
+5. bison 2.3 or higher
+6. Ruby 2.2 or higher
+
+When building from a released version, only a C99 compiler and GNU or BSD make
+is required.
+
+## How to compile and install
+
+1.  If you want to use Microsoft Visual C++ to compile Ruby, read
+    [win32/README.win32](win32/README.win32) instead of this document.
+
+2.  Run `./autogen.sh` to generate configure, when you build the source checked
+    out from the Git repository.
+
+3.  Run `./configure`, which will generate `config.h` and `Makefile`.
+
+    Some C compiler flags may be added by default depending on your
+    environment. Specify `optflags=..` and `warnflags=..` as necessary to
+    override them.
+
+4.  Edit `include/ruby/defines.h` if you need. Usually this step will not be needed.
+
+5.  Optional: Remove comment mark(`#`) before the module names from `ext/Setup`.
+
+    This step is only necessary if you want to link modules statically.
+
+    If you don't want to compile dynamic extensions (probably on architectures
+    which do not allow dynamic loading), remove comment mark from the line
+    "`#option nodynamic`" in `ext/Setup`.
+
+    Usually this step will not be needed.
+
+6.  Run `make`.
+
+    * On Mac, set RUBY\_CODESIGN environment variable with a signing identity.
+      It uses the identity to sign `ruby` binary. See also codesign(1).
+
+7.  Optionally, run '`make check`' to check whether the compiled Ruby
+    interpreter works well. If you see the message "`check succeeded`", your
+    Ruby works as it should (hopefully).
+
+8.  Run '`make install`'.
+
+    This command will create the following directories and install files into
+    them.
+
+    *   `${DESTDIR}${prefix}/bin`
+    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}`
+    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
+    *   `${DESTDIR}${prefix}/lib`
+    *   `${DESTDIR}${prefix}/lib/ruby`
+    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}`
+    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
+    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby`
+    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}`
+    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
+    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby`
+    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}`
+    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
+    *   `${DESTDIR}${prefix}/lib/ruby/gems/${MAJOR}.${MINOR}.${TEENY}`
+    *   `${DESTDIR}${prefix}/share/man/man1`
+    *   `${DESTDIR}${prefix}/share/ri/${MAJOR}.${MINOR}.${TEENY}/system`
+
+
+    If Ruby's API version is '*x.y.z*', the `${MAJOR}` is '*x*', the
+    `${MINOR}` is '*y*', and the `${TEENY}` is '*z*'.
+
+    **NOTE**: teeny of the API version may be different from one of Ruby's
+    program version
+
+    You may have to be a super user to install Ruby.
+
+If you fail to compile Ruby, please send the detailed error report with the
+error log and machine/OS type, to help others.
+
+Some extension libraries may not get compiled because of lack of necessary
+external libraries and/or headers, then you will need to run '`make distclean-ext`'
+to remove old configuration after installing them in such case.
+
+## Copying
+
+See the file [COPYING](COPYING).
+
+## Feedback
+
+Questions about the Ruby language can be asked on the [Ruby-Talk] mailing list
+or on websites like https://stackoverflow.com.
+
+Bugs should be reported at https://bugs.ruby-lang.org. Read [HowToReport] for more information.
+
+[Ruby-Talk]: https://www.ruby-lang.org/en/community/mailing-lists
+[HowToReport]: https://bugs.ruby-lang.org/projects/ruby/wiki/HowToReport
+
+## Contributing
+
+See the file [CONTRIBUTING.md](CONTRIBUTING.md)
+
+## The Author
+
+Ruby was originally designed and developed by Yukihiro Matsumoto (Matz) in 1995.
+
+<matz@ruby-lang.org>