You can download the source code for Frontier 10.0a1:
FrontierKernel-10.0a1.sit (Mac OS)
The only difference between the two downloads is the compression method used. The contents of the archives are identical.
The source code is set up to compile with CodeWarrior Professional 8 for Mac or Windows (with the 8.3 updates).
Please refer to the Build instructions in the README.txt file included with the downloads for further information.
Minimal Application Install
We put together minimal installations for all three target platforms to allow developers to test the applications compiled from the source code.
These installations only contain the Frontier application, Frontier.root and a few other support files. They do not include other database files like mainResponder.root or prefs.root which are available as separate downloads.
Minimal Install: Mac OS X
Download Frontier-10.0a1-osx.dmg and double-click the downloaded file if it is not being mounted automatically. Drag the Frontier folder from the disk image to your hard disk. Double-click the UserLand FrontierTM application in the Frontier folder to launch it.
Minimal Install: Mac OS 7.5.5 to 9.x
Download Frontier-10.0a1-ppc.sit and expand the StuffIt archive. Double-click the UserLand FrontierTM application in the resulting folder to launch it.
Minimal Install: Windows
Download Frontier-10.0a1-win.zip and unzip the archive. Double-click the Frontier.exe application in the UserLand Frontier folder to launch it. Instead of displaying an MDI window, the Frontier icon will appear in the system tray. To access the Frontier user interface after launching the application, select the Open Frontier command from the context menu of the Frontier icon in the system tray.