What tools are built using themselves? [closed]

Question

I am curious about what tools are used to build the next version of themselves.

For example, Delphi has long claimed that "Delphi is written in Delphi".

I assume Visual Studio is written using Visual Studio.

What are some other examples of tools that written in themselves?

Answer 1

Bjarne Stroustrup mentioned in The Design and Evolution of C++ that the first C++ compiler was written in C++.

I've just noticed this is also a question in his FAQ:

The first C++ compiler (Cfront) was written in C++. To build that, I first used C to write a "C with Classes"-to-C preprocessor. "C with Classes" was a C dialect that became the immediate ancestor to C++. That preprocessor translated "C with Classes" constructs (such as classes and constructors) into C. It was a traditional preprocessor that didn't understand all of the language, left most of the type checking for the C compiler to do, and translated individual constructs without complete knowledge. I then wrote the first version of Cfront in "C with Classes".

Answer 2

Interestingly, the VB.NET & C# compilers themselves are written in unmanaged C++ (leading to the C++ team's T-Shirt: "My compiler compiled yours"). The C# team hopes to have a fully managed-C# hosted C# compiler for VS2010.

Answer 3

This is off-topic, but strictly speaking, it is an example of a tool which builds itself.

The reprap - an open-source 3d prototyping machine, which recently gave 'birth' to "its first complete working replicated copy".

I love this kind of stuff.

Answer 4

Generically speaking, C compilers are usually written in C... *nix kernels are compiled on *nix, etc.

Answer 5

Also, there's the pypy project which provides a Python interpreter written in Python.

Answer 6

When gcc (the Gnu C compiler http://gcc.gnu.org/) was not available widely, you had to compile it from source, compiling stage1 compiler, then compile stage2 with stage1, till you have your final compiler. I assume it must be the same today.

Answer 7

Here is another example: Mono's C# compiler is self hosting - i.e. it's written in C# and used to compile itself.

Dog fooding refers to the more general practice of a company using its own product internally, especially during its development.

Answer 8

Lots of folks like to look at how Lisp can be implemented in Lisp.

Answer 9

Squeak is a Smalltalk-80 implementation written in itself.

even its virtual machine is written entirely in Smalltalk making it easy to debug, analyze, and change.

Answer 10

Sun's Java compiler has long been written in Java. However, recent work is writing a JIT compiler in Java as well. This is the JVM component that converts Java byte code to native processor instructions.

Answer 11

We use to develop using RealBasic. The IDE is written in itself, or so I've been lead to believe.

Answer 12

ghc, the Haskell compiler, is mostly written in Haskell.

Answer 13

tcc is another self-hosting C compiler for x86 and ARM. Its claim to fame is being, well, tiny (100k or so for preprocessor, compiler, assembler, and linker).

Answer 14

I would assume that pretty much any tool that's part of the typical development process would be involved in its own development, to whatever extent possible. This includes:

• certain programming languages, especially compiled ones
• IDEs
• text editors
• version control systems
• bug trackers
• build systems

If you're on a team building one of these tools, and you're not developing it for a specific niche that doesn't apply to your team, I don't know why you wouldn't use it to build itself. Having developers be users of the product is one of the best ways to find possible improvements.

Answer 15

For the AmigaOS there was a third party Basic interpreter (don't remember the name) for which you could later buy a compiler. The compiler was delivered as source, so you had to use the interpreter to run the compiler to compile itself...

To cite Kent Beck:

...it may seem a bit like performing brain surgery on yourself.

Answer 16

Visual Studio and Team Foundation Server build themselves. It's called dogfooding, a term which if not originating in Microsoft, it certainly likes

Answer 17

Oracle Application Express is a web application development tool that is built in itself.

Answer 18

Eclipse IDE is generally built and developed using Eclipse IDE.

Answer 19

It is fairly typical to have a languages compiler written in its own language. This is called self-hosting or bootstrapping.

Answer 20

Maven2 is built using Maven2. Ok, it's not built (i.e. written) using itself, as it is a tool to build (i.e. compile) project, but it is using its own code to compile...

Answer 21

I was amazed with JSLint

In short it has been described as Javascript "compiler" using javascript.

Answer 22

I am building an IDE-based code generator, and I am using it to build itself. If fact, as Stroustrup did, I am first building a valid generator model and using a pre-processor to build the final C++ code to compile. Once I have a good working version of the IDE, I'll start using it to build further versions of itself.

It's like giving a new dimension to the meaning of "recursive programming"!

Answer 23

AFAIK does the OpenJDK build itself first with the installed java and afterwards with itself.

Answer 24

Naturally the Jetbrains team uses its own IDE IntelliJ IDEA to develop this IDE.

I assume this is true for most IDE vendors.

Answer 25

As far as I know, when building EMACS from source, all of the ELISP code is bootstrapped. I found that quite noteworthy.

Answer 26

Not quite what you're asking for, but the entire development environment for Revolution http://www.runrev.com is built using Revolution itself, and the source (except for small parts that enforce the license) is completely exposed in source form. So if you don't like the way the dev environment is implemented, you can change it. Find a bug, fix it. You can also easily build additional development tools and integrate them.

Answer 27

Ada and Forth

Answer 28

I gave the Smalltalk-80 answer an uptick. Best, most elegant example I can think of. The question also reminds me of a slightly related problem that used to be popular: write a program that outputs itself. Not the same level of bootstrapping, but a fun little programming puzzle for your amusement. Maybe not possible in all languages?

Answer 29

The old Watcom C/C++ compiler was built using itself.

Answer 30

Kragen Sitaker's Ur-Scheme is a fine example of a small nontrivial compiler written in itself. That page links to several more good sources in that vein.