Comex released an alpha version of Substitute on his github page and noted his motivation behind the project. His goal is to make as much low-level software as open as possible and currently Cydia Substrate is closed source.
Jailbreaking is fundamentally about taking something closed and fixed and opening it up to hacking and modification: perhaps allowing a mess to be made, but quite possibly ending up with something unique and different. This ideal of openness is very similar to that of free software, and I therefore believe that it's in the spirit of jailbreaking to make as much low-level stuff open as possible, both for inspection and modification by curious users (who, after gaining knowledge that way, might end up becoming quite valuable to the community). Polished tweaks that are sold commercially are one thing (although they too benefit from general openness, especially the ones with a lot of reverse engineering behind them, since the same reverse engineering can often support multiple use cases), but the underlying framework is another - especially since it's free of charge, removing at least the most obvious motivation for closing source.
Saurik (Jay Freeman) replied to Comex's Cydia Substrate replacement in a lengthy blog post. Saurik first explained why Substrate has remained closed source.
Open source software merely existing does not lead to open platforms, as the priority of the vast majority of users align with short-term interests (for various reasons, some good and some bad) and so they will happily buy into and empower closed platforms in order to get a relatively small amount of functionality, comfort, or glitter (see iOS itself ;P)....I do this because we are fighting a battle against companies—not just companies like Apple, but companies like Rock Your Phone and iMods—who want to see "open" be traded away for "ease of use" or "profitability".
Additionally, Saurik notes that he is running out of energy to "fight" against people who are not on his side. His biggest focus for now is the DMCA exemption comment period; (keeping jailbreaking legal) however, he does not some new features are coming to Cydia in the near future.
This push is going to come with some style updates to Cydia's home page, so you will see those changes, and there are a couple payment related things that are "almost done" which will happen in the near future. I also have some changes I was working on to Substrate (a different way of loading and filtering that is finally ready, that will come with an easier-to-use SDK) that will probably be released. We will see if it makes sense for me to continue bothering
You can read Saurik's full blog post and reasoning here. Let us know what you think in the comments. Will a Cydia Substrate alternative help the community or do damage to it?
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