CrossBridge is the open-source version of Adobe FlasCC (formerly the Alchemy project).

Combine the power, familiarity, and high-performance of C/C++ with the unparalleled reach of the web. With CrossBridge you can bring your native C/C++ from consoles and PCs to over a billion people on the web – across browsers, with no additional install.

Stunning native games, welcome to the stunning reach of the web.

Play the Epic Citadel demo

Watch the Epic Citadel demo.

What is CrossBridge?

Previously codenamed "Alchemy," CrossBridge provides a complete BSD-like C/C++ development environment based on GCC that lets you compile your C/C++ code to target the Adobe Flash Runtimes (Flash Player and AIR). With CrossBridge you can port almost any existing C/C++ code to the web, across browsers.

CrossBridge includes tools for building, testing, and debugging C/C++ projects, example projects with source code, and documentation.

Watch the CrossBridge video

Stunning C/C++ console games. In your browser. No friction.

CrossBridge brings the power of C/C++ games and libraries—including the leading game engines on PCs, Xbox 360, and PlayStation 3—to the web. Efficient sandboxing across browsers with incredible performance, debugging support, and seamless integration with ActionScript APIs allow developers to re-use fast, mature C/C++ code bases—even massive games with hundreds of millions of lines of code—and combine them with rich Flash technology APIs. Leverage OpenGL or DirectX with programmable shaders via Stage3D hardware acceleration, dynamic low-latency sound, multiplayer networking, and instant play with streaming assets directly on the web.

CrossBridge technical info

The CrossBridge SDK gives you everything you need to efficiently port your code to the Flash Runtime:

  • Use your existing C/C++ project files and makefiles. If you're already using GCC, just drop in CrossBridge to target Flash Player with your existing C/C++ code.
  • Debug your code running in the Flash Runtime with GDB, just like your native toolchain.
  • Access the entire Flash Runtime API from C++ classes, including Stage3D for OpenGL/DirectX GPU accelerated graphics.
  • Leverage extensive documentation, tutorials, and working examples of C/C++ libraries ported to the Flash Runtime, including Lua, Box2D, and Bullet physics.
  • Take advantage of Pthreads multithreading support in the upcoming Flash Player 11.5.
  • CrossBridge also lets you use C/C++ to create libraries (SWCs) for ActionScript developers: Use SWIG to automatically create AS3 interfaces to C code.

Demo: Epic Citadel

Epic Citadel

Epic Games worked with Adobe to take advantage of the Flash C++ Compiler to bring Unreal Engine 3 to the web. The same breathtaking game engine that powers best-selling Xbox 360 and PlayStation 3 games like Gears of War 3, Borderlands, and Mass Effect 3 now runs on one billion computers (see a video).

By taking advantage of Stage3D hardware acceleration in Flash Player, C/C++ content like Epic Citadel can run directly across browsers with stunning efficiency. Experience it yourself, and welcome to a new level of gaming on your favorite websites.

"Games built for high-end consoles can now run on the Web or as Facebook apps, reaching an enormous user base. This totally changes the playing field for game developers."

Tim Sweeney, Founder, Epic Games

"The Flash Player version of Unreal Tournament 3 turned out to look even better than the version we shipped on Xbox 360 and PlayStation 3."

Mark Rein, Vice President, Epic Games

View demo

CrossBridge FAQs

See the CrossBridge discussion forum for answers to frequently asked questions.

Minimum system requirements

  • Flash Player 11 or higher
  • Flex SDK 4.6 or higher
  • Java Virtual Machine (64-bit)


  • Microsoft® Windows® 7 (64-bit edition)
  • Cygwin (included)

Mac OS

  • Mac OS X v10.6 or higher