Try Dafny

The easiest way to get started with Dafny is to use rise4fun, where you can write and verify Dafny programs without having install anything. On rise4fun, you will also find the online Dafny tutorial.

Install the binaries

To install Dafny on your own machine, download Dafny.zip and save it to your disk. Then, before you open or unzip it, right-click on it and select Properties; at the bottom of the dialog, click the Unblock button and then the OK button. Now, open Dafny.zip and copy its contents into a directory on your machine. (You can now delete the Dafny.zip file.)

You will also need to install Z3 (version 4.1 is recommended).

Then:

• To run Dafny from the command line, simply run Dafny.exe (or the Verification Debugger, BVD.exe) from that directory.
• To install Dafny for use inside Visual Studio 2012, double-click on DafnyLanguageService.vsix to run the installer. Then, whenever you open a file with the extension .dfy in Visual Studio, the Dafny mode will kick in. You may first need to uninstall the old version of the extension from within Visual Studio (Tools ==> Extensions and Updates). (If you don't intend to run Dafny from the command line, you can delete the directory into which you copied the contents of Dafny.zip.)