Once you get the basic idea of how it all works then, despite the earlier claims, it isn't that difficult to create an add-in. The big problem is that the lack of documentation and good explanations of how it all works means that the barrier to getting started with any Gecko based application is very high. Essentially the effort of learning a new UI and development producedure was the problem.
You need to keep this thought in mind as you read on.
As well as making Addons easier to create Jetpack is also implementing a sandbox type security system that limits what an Addon can do.
It is still early days as evidenced by the fact that the version number is only 0.5 but the team plan to have a first complete version by the end of the year.The SDK includes many core features including an API for a context menu, widgets, storage, and page workers. The latest version ads APIs for tabs, requests, load and unload handling, localization, selection text editing, There are still a lot of desirable features missing such as a layout panel that will make more complex users interfaces easier to create.
If you are a would be Firefox add-on programmer then it's an exciting time but...
The first question is why does anyone thing that there is a pent up demand to create Firefox add-ons?
If you visit the Firefox add-on site then you will discover that there doesn't seem to be any supply problems.
The second question is how can a project that aims to make an aspect of programming easier hope to be taken seriously when its documentation is non-existent. There is a very good argument that instead of launching a new way to create Firefox add-ons time and effort spent documenting the original XUL/XCOM way of doing the job would be a better idea.
Currently the Jetpack SDK documentation is worse than useless. There are far too many blank pages promising documentation in the future. There are also too many flaky web page links, old documentation that has been removed but not replaced and cryptic comments from the programmers "in the know". This isn't the way to attract new blood into this particular area of programming.
The end result is that, if you know what you are doing then it is easier to create an add-on. If you don't know what you are doing then getting started is very difficult. At the time of launching the SDK there wasn't even a simple Hello World type add-in could be used to get the environment set up - but having noticed this omission I decided to write one myself - see Getting started with Jetpack.
Almost certainly not - unless of course they rely on additional help from iProgrammer.
Extending Firefox and Thunderbird
Getting started with Jetpack