Getting Started

Running Online

The easiest way to try Frost is to use the online demo, which includes a number of example programs. The instructions below are for building and installing Frost locally.


Frost currently only works under Linux and MacOS. Building Frost requires the following prerequisites:

Make sure that all of these software packages are available on your PATH.

Building Frost

MacOS, Linux

Frost's source repository is located at Clone this repository using Git and cd into it:

$ git clone
$ cd Frost

Then create a build directory and run cmake:

$ mkdir build
$ cd build
$ cmake ..

Assuming cmake finds all of the prerequisites, you should now be able to build Frost:

$ make -j

(Note: if you encounter any errors with locating or linking to LLVM or ICU, set the LLVM_DIR or ICU_DIR environment variable to the appropriate installation directory and re-run cmake.)

This will create the frostc compiler in the build directory. You can run Frost's tests to ensure that it is functioning correctly:

$ make run_tests

Note that a handful of tests are expected to fail at the moment.


Install Visual Studio Install cmake Download ICU (as of this writing, and unzip to a directory of your choice Start a Visual Studio Developer Command Prompt

> git clone
> cd Frost
> mkdir build
> cd build
> set ICU_ROOT_DIR=<path where you unzipped ICU>
> set CC=clang-cl
> set CXX=clang-cl
> set CFLAGS=<-m64 or -m32 depending on whether you are on a 64 bit or 32 bit system>
> cmake -G "NMake Makefiles" ..
> nmake

"Hello, World!"

Once you have built frostc and verified that it works, add its directory to your PATH and create a simple Frost program:

method main() {
    Console.printLine("Hello, World!")

Save this file as hello.frost. Now compile and run it:

$ frostc hello.frost
$ ./hello
Hello, World!

Congratulations, you have successfully run your first Frost program! See the overview for a rundown of Frost's basic features.