Gulden was founded in April 2014 based on the Litecoin code base. In 2015 the Litecoin codebase is abandoned and Gulden switched to the Bitcoin codebase. After years of development it can be said that Gulden now has its own code base. Gulden started with a 10% premine that was spent entirely on development. The current developments are now paid by a part of the mining reward. The direction of the developments are determined by the Gulden advisory board (GAB). The GAB consists of 9 members and is elected each year from the members of the community. Anyone can stand for election. Voting for candidates is recorded and done through the Gulden blockchain. Gulden would like to become a generally accepted means of payment. To this end, the development is aimed at making the wallets as user-friendly as possible.

Features of Gulden:

PoW2

Gulden does not use a standard PoW consensus model, but the in-house developed PoW2 model. This is a combination of PoW and Witness. Miners control the transactions and the Witness controls the miners. Anyone can become a witness by locking an amount of Gulden in a Witness account in the desktop wallet for a certain amount of time. Depending on the weighting of this witness account (chosen duration and amount in the account) the witness earns rewards. The advantage of this system is that the Gulden blockchain can withstand 51% attacks without relying heavily on energy-guzzling PoW miners or vulnerable standard PoS systems. Transactions can be safely accepted after one confirmation instead of the standard 3-6 confirmations.

More info: The Technical Documentation link above which contains the whitepaper for PoW2 or https://medium.com/@aat.de.kwaasteniet/gulden-witnessing-163cb0eae289

Linking:

The desktop wallets can contain multiple accounts and mobile wallets can be linked to a single account in the desktop. For more info: https://medium.com/@aat.de.kwaasteniet/gulden-mobile-wallet-linking-to-desktop-wallet-eff117eb208f

SIGMA:

Since October 17, 2019, the Gulden team has implemented the Sigma algorithm and since then it is possible to mine Gulden solo without additional equipment. The algorithm is asic resistant and can be done on a normal desktop computer using it’s CPU. One can simply use this CPU mining algorithm by creating a mining account in the desktop wallet and start mining Gulden. more info: https://medium.com/coinmonks/mining-gulden-d4fe8c690939