PNaCl : Portable Native Client Executables

While the operating-system neutrality of Native Client tends to encourage good practices with respect to ISA portability, the burden of building, testing and deploying a program on all supported hardware platforms---currently IA-32, ARM and x86-64---lies with the developer. This arrangement makes it too easy for the developer to fail to support one or more ISAs, and tends to create a barrier for future new ISAs, threatening the portability promise of the Web.