Mozilla's current tentative plan is to adopt a slim layer of existing code from the lower levels of the Android operating system for hardware enablement purposes and then build a completely custom user interface and application stack around Gecko, the Firefox HTML rendering engine. Android was chosen because it will theoretically offer compatibility with existing hardware, but Mozilla ultimately intends to use "as little of Android as possible." It will not use Android's Java-based environment and it will not support programming in native code.