Squeak runs on a virtual machine (VM), allowing for a high degree of portability.

While source code was available and modification permitted, the Squeak License contained an indemnity clause that prevented it from qualifying as true free and open-source software.

However, The Apple Public Source License fails to conform to the Debian Free Software Guidelines.

To enable inclusion of Etoys in the One Laptop Per Child project, a second relicensing was undertaken using the Apache License.

At this point, an effort was also made to address the issue of code contributed by members of the Squeak community, which it was not in Apple's power to unilaterally relicense.