Mono Packager and the Apple AppStore

We are happy to announce the Mono Packager for OSX.

MonoDevelop UI for Mac Packages and Installers.

The Mono Packager for OSX makes it possible to create self-contained Mono applications that will run on OSX without requiring the Mono.framework to be previously installed on the system. In combination with the MonoMac project you can build fully native MacOS X applications using your favorite .NET technologies. From your choice of Mono/.NET languages, to your choice of Mono/.NET library.

The packager can create both signed applications for distribution on the Mac AppStore, as well as creating installers for your software.

Mono on the Mac: Some Background

Mono on OSX has historically been distributed as an image that installed itself in /Library/Frameworks/Mono.framework. Once Mono was installed, users could write code in C# or their favorite .NET/Mono language and run the resulting executable.

The problem is that Mono.framework contains an entire development stack: compilers, GUI tools, command line tools, libraries, documentation which is convenient for developers, but most of the time, not very useful for end-users.

This meant that developers would typically ask users to first install the Mono.framework (a big download) and then they could install their applications.

To work around that problem, some developers have chosen to manually embed Mono in their applications. This has always been possible, but it was error-prone as developers would have to manually assemble Mono into their application bundle, configure Mono properly, and initialize the Mono runtime themselves. Doable, but not pleasant.

With today's release, we have taken the burden of creating self-contained Mono applications out of developer's hands and added it as a standard feature for developers to use.

The Mac AppStore

The Mac AppStore requires that applications submitted to it are completely self-contained and they do not depend on third-party frameworks to be installed on the system. It also requires that your application and installer be signed.

Both of those features are supported in our MonoMac Packager. Developers can now create Mac AppStore ready applications using MonoDevelop and MonoMac. We have integrated the package creation, installer creation, and signing processes into our MonoDevelop IDE.

All that developers have to do is sign up for Apple's Mac developer program, get their distribution certificates, build a fabulous application and upload the application using the Application Loader to

Upcoming: Linking

In this version of the Mac bundler, we include all of the dependencies that your program takes. For example, if you use the System.Xml library, the entire System.Xml library will be bundled with the application.

In our next release, we will add support for Mono's linker, the same technology we used in MonoTouch to reduce the executable size.

When you choose to use use the linker, the granularity of distribute changes from the library-level to the type level. For example, if you only use one type from System.Xml, the linker will strip out all of the unused classes and generate a new System.Xml library that only contains the one type that you used.

We did not want to wait for the linker to be ready before shipping our packager, but we should have it ready soon.

MonoMac Refresh

As part of this release we have also issued a refresh to the MonoMac library and templates.

From now on, MonoMac binaries will default to be 4.0 profile, allowing users to leverage all of the new features in the C# 4.0 language (like dynamic) as well as the new .NET 4.0 APIs that we introduced with Mono 2.8.

The updates to the MonoMac API are described in my other blog post.

Posted on 10 Jan 2011 by Miguel de Icaza
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