Why are the SDK and sidechains at the end of the roadmap?
The main reason is that we require the time to mature the foundations of the Lisk blockchain application platform by implementing a number of important changes into the Lisk protocol.
Work on the SDK actually starts towards the beginning of the roadmap, especially with regard to the TypeScript migration from Lisk Core to Lisk Elements and the proposed new application architecture. The key milestones for the SDK are to be delivered within scheduled alpha, beta and release candidate phases. During each phase a continuous feedback loop needs to be maintained with the development community to ensure the SDK is as expected and as we envisioned.
We have positioned the implementation of our sidechains solution towards the end of the roadmap as we see this as a hard problem, one that requires extensive research.
We want to allow sidechain communication in a scalable, trustless and decentralized manner. This is not a trivial problem and is yet to be solved industry wide. Currently, there are solutions which solve the problem of cross-chain communication in a centralized manner, which would be straightforward to implement, however as proponents of decentralization, this is not the solution we will be opting for.
Furthermore, as part of our overarching goal of creating a blockchain application platform, it is not required that we implement sidechain communication early on. This means that users can build their blockchain application and then plug in sidechain communication once it is completed, rather than waiting until the entire platform has been built.
We also need the time to gather consent from the community on our proposed changes.