Currency networks are getting a protocol upgrade.

Before, we talked about the currency networks on Trustlines in another post. The currency networks are shared platforms and are not controlled by a single party. While anyone could create their own, the Trustlines Foundation has deployed 46 initial currency networks for anyone to use.

Their purpose is to let people choose their preferred denomination for recording transactions. On a technical level, the currency networks in the Trustlines Protocol are smart contracts that track IOUs (I owe you). And smart contracts are not necessarily upgradeable. A simple smart contract used to be of a type of "deploy and forget."

When we developed the first versions of our smart contracts, we faced a problem. What if there was an unforeseen error in them? How could we prevent users from using the vulnerable contracts?

That's why we built in the option to freeze a currency network. That option becomes available on the 15th of February 2021. We've decided to activate the switch and freeze all activity in the previously deployed currency networks. Since the current versions are not upgradeable, we have to perform a migration. The upgraded contracts are upgradeable and intended to be governed by the Trustlines Network.

We've made a snapshot of all currency networks' states on the 15th of February 2021 and re-deployed them. We've then migrated the old states to the new currency networks. As a user, you will continue to transact with your partners without having to do anything on your end.

And if you want to look at all your past transactions in the frozen/archived networks, you can still do that. One option is to use our Trustlines Blockchain Explorer. Or by navigating to the "Currencies" -> "Archived currencies" screen in the Trustlines App and re-enabling an archived network.

Note that you can no longer transact in the archived networks. These networks are only for viewing so that you can inspect your past transactions in them.

For the past two years, the blockchain world has evolved, and "upgradeable-proxy contracts" are more commonly used. We've chosen to implement the Proxy-Beacon pattern. If you're curious to learn more about upgradeable contracts, check out this excellent overview of upgradeable smart contracts.

The State of Smart Contract Upgrades
The State of Smart Contract Upgrades – 2020 edition A survey of the different Ethereum smart contract upgrade patterns and strategies from a technical viewpoint, plus a set of good practices …

If you run into problems while using the Trustlines App, you are likely using an old version with the frozen currency networks. This is easily fixed by upgrading to the latest version of the Trustlines App.

Start creating trustlines

Head on over to and start using the Trustlines App with your friends now!

Trustlines App - Economic inclusion for all
The Trustlines App reflects the idea of people-powered money where value can be created and managed by each individual without any intermediaries

We look forward to hearing from you!

Join the community at the Trustlines Forum, follow us on Twitter, and be sure to subscribe to the Trustlines Blog for all the latest news!