Introducing z:kv - a key-value store entirely on Zcash
Alpha testers wanted! Try our first release: zec.rocks/zkv
z:kv stores a signed key-value log entirely on the Zcash blockchain. Readers reconstruct state by scanning the chain with a viewing key and replaying the signed memos.
It’s a new way to store information on Zcash. It’s great for public “small data” that benefits from decentralization: price oracles, feature flags, release announcements, and, well, anything!
The z:kv spec aims to be simple. It’s inspired by Redis, and is essentially “SET (key) (value)” in a signed Zcash memo. Signatures use a T-address key for wide support across Zcash libraries, but all data is stored shielded.
A testnet faucet is available within z:kv Browser to get you started quickly.
I sat on this idea for a long time, the hackathon at the Zcash Dev Summit last month in Rome inspired me to race through the initial implementation. (thank you to my awesome hackathon team members @azmr @nachog00 @philliptrudeau and of course the Zcash Foundation)
My goal is to reduce our wallets’ need to make HTTP requests to look up data like the current Zcash price, potentially exposing user IPs. Let’s Zcash all the things.
The plan is to keep iterating on this initial approach based on community feedback, and to migrate over to using UIVKs once librustzcash supports them, for z:kv database operators to not need to reveal outbound transactions.
I’m excited to hear your feedback!
Here’s an example database to import, illustrating what a wallet could have for its feature flags:
zkvtest1sv30yl48750pcp6vvp69gnyuwu3szkh7rd4c2fp697umvqctwushne0upxfz8mx6mutx5gcavuuwxgw72juzv2va3v0rxumgx36gjs0f66almkcwry2gga84w0z0tjdfp43vykckt2qu0nkz5c2c7efedkjddstdrsfzvrlgwtmnnw05v0rk5hng3dq3y3s22y6d5ct00u6g4vrranefw88jpjl9d7a2zfu3nwrxd2zsk4sff4dnx40s92nfx8e7fgr8uctwhgsjs3um4xg5a49ysx6cs3x9ar5vuum0kvdm07q68jnsag0xnaa43kmv7vkm9ek678dvppf2rh8ysafgtr432skfx2ytzwp2txf
