Over the summer, the CityCoins community developed a four-phase plan to stabilize the protocol. The phases were split into two separate CityCoins Improvement Proposals (CCIPs): CCIP-012 and CCIP-013.

Implementation for CCIP-012 and CCIP-013 has now concluded:

• Voting on CCIP-012 passed on Monday, 19th September with 86% of votes in favor of the proposal.

• The community’s work to implement CCIP-012 was completed on September, 26th 2022.

• Voting on CCIP-013 passed on Tuesday, 1st November with 88% of votes in favor of the proposal.

• Work to implement CCIP-013 was completed on February 27th, 2023.

To recap, the following upgrades to the CityCoins protocol are now live:

1. Annual Emissions rate has been reduced to near 2% (subject to whether blocks are mined)
2. CityCoins treasuries are secured in new Smart Contract Vaults:
   • Each city now has a dedicated (a) Mining Treasury and (b) Stacking Treasury
   • Each treasury can be delegated for stacking through PoX
3. CityCoins contract design has been simplified
4. Registration, mining and stacking flows have been upgraded such that:
   • 100% of STX spent mining CityCoins now go directly to the city’s Mining Treasury
   • The Mining Treasury is automatically delegated and stacked, and rewards paid to the stacking treasury in STX
   • CityCoins stackers can now claim their portion of those stacking rewards from the city each cycle

What does this mean for CityCoins?

Work to implement CityCoins’ community-voted stabilization process is now complete.

CityCoins remains fully functional, and these stabilization efforts afford developers who wish to continue building with CityCoins the opportunity to build on a protocol that is far more robust and durable.

The CityCoins treasuries remain secure and available for their respective cities to use at their discretion.

What does this mean for CityCoins Holders?

This change complements an increase of 30% → 100% mining throughput directed to each respective CityCoin treasury. Rewards from stacking no longer come from mining throughput.

The STX in the CityCoins mining treasuries are now automatically stacked to earn STX, with 100% of the reward now automatically distributed to CityCoins holders who stack their CityCoins.

What does this mean for CityCoins Miners?

If you are mining via a web interface such as minecitycoins.com or syvitamining.com, there should be no visual change.

If you are mining via scripts published in the CityCoins org, updated versions are now available. Feedback and contributions are welcome.

If you are mining via making direct contract calls, the address, contract name, and function signatures will need to be updated. This is generally relevant for anyone providing mining operations on the CityCoins protocol.

If no one is mining a given block, that block’s reward will be skipped, and that block will not mint new CityCoins.

After the old contract is shut down, any mining transactions will fail but any mining claims up to the shutdown height will still succeed.

After the new contract activates, mining claims will be available as soon as they mature after 100 blocks, the same as before.

What should you do if you are currently stacking?

All currently stacked CityCoins were automatically unlocked when the protocol upgrade was completed. If you wish to continue stacking you must take the following actions:

1. Claim your CityCoins from the old contract. (you can use this helpful tool to see stacking data)
2. Stack your CityCoins in the new contract.

If you are stacking through a web interface such as minecitycoins.com or syvitamining.com, there should be no visual change.

If you are stacking by making direct contract calls, the address, contract name, and function signatures will need to be updated. This is generally relevant for anyone providing stacking operations on the CityCoins protocol.

After the old contract is shut down, it will be possible to claim for the current and future stacking cycles. If you stacked multiple times, multiple claims will be required.

For example:

If Alice stacked 1,000 MIA cycle 30 to 42, then she would be able to claim her 1,000 MIA back from cycle 42

If Bob stacked for multiple cycles, ie:

• 1,000 MIA from cycles 30 to 45
• 1,000 MIA from cycles 31 to 46
• 1,000 MIA from cycles 32 to 48

Then Bob would be able to claim:

• 1,000 MIA from cycle 45
• 1,000 MIA from cycle 46
• 1,000 MIA from cycle 48

After the new contract activates, stacking cycles will be the same length and duration of Stacks stacking cycles.

Same as before, CityCoins stacking always begins in the next cycle and there is a one cycle cooldown period in-between claiming and stacking again.

What to do if you want to build with CityCoins

We’d like to thank every member of the community for their work to develop and implement this four-phase protocol upgrade plan, as well as all CityCoiners who voted on CCIP-012 and CCIP-013 to implement the plan.

If you are interested in building with CityCoins we encourage you to visit the resources below:

• the CityCoins Protocol Documentation
• the CityCoins Protocol API and related documentation
• the CityCoins GitHub Organization