Weekly Engineering Update - Sphere by Horizen: Progress on performance issues, adding new UX component for users, reducing the time taken to synchronize wallet addresses, added infographic on the addresses refresh progress. New build sent for testing. - Block Explorer: Progress with mainchain Block Explorer update related activities. - Horizen Sidechains: Continued the consensus and stake delegation implementation strategy regarding NodeviewHolder processing logic changes and the Sidechain History updates. Detailed the next steps for the consensus implementation. - Mainchain changes required by the sidechain model: Continued the developments for the required changes to allow backward transfers. First review will be upcoming. - Mainchain changes for sidechain support: Identified necessary improvements. Began working on fix. - New whitepaper: First review complete and was positive. Second round upcoming.