The Blockchain is a global database, secured by thousands of computers around the world. Imagine it as a big Excel spreadsheet where only the owners can change the values in their own cells, but everyone can see what's in everyone else's cell. For more information, please read this introduction.


Ethereum is an advanced blockchain which makes money programmable. While Bitcoin's blockchain allows for censorship-resistant global financial transaction, Ethereum goes a step further allowing for the creation of eternal programs (smart contracts) that remain in operation indefinitely. For more details and abilities of the Ethereum blockchain, and for a comparison with Bitcoin's blockchain, please read this introduction.


Given that running smart contracts on the Ethereum blockchain costs money (Ether), testing on it is expensive and impractical. Testnets are private copies of the Ethereum blockchain (just its protocol, but not its data) which serve the purpose of being playgrounds for developers. For more information about the idea of testnets and the way to join some others, please read this introduction.

Learn through testing

Empowering the local
Ethereum community

The Lisinski testnet is available to all, for free

To learn how it came to be, please watch this talk by Nikola Jokić at the conference.


Experimenting together

The Ethereum community in Croatia is currently fragmented. A common local testnet will let the different teams collaborate much better.


It's free

The testnet is volunteer-run and no type of payment or usage fee is needed to join the network or use it for your apps.



Various events emphasizing cooperative or competitive coding on the blockchain can benefit greatly from a local but public blockchain on which to not only demonstrate their prototypes but also their compatibility with other, already deployed software.



The blockchain can be used to demonstrate various prototypes to the ruling caste and show the government et al. that blockchain is nothing to be afraid of. In fact, a national testnet allows us to deploy things like a national stablecoin, land registry on the blockchain, a proof of concept elimination of the administrative layer from government services, and much more.



While we already have a rich corpus of educational technical writings on in both English and Croatian, growing the local Ethereum network will only enhance this and produce more excellent material.



The cooperation of various Ethereum-focused teams in this area will foster the growth of blockchain technology in the region, rapidly forming new partnerships, ideas, and interesting projects.

How to connect to the Lisinski testnet through RPC?

With a bit of effort, it's easy to connect to any of the open Lisinski member nodes and use it to send transactions and query blockchain records. It's even easier to open your own node to RPC calls and achieve ultimate security.

How to spin up your own Lisinski node and sync it to the network?

A guide on configuring a Geth instance on your computer or server. Sync your own copy of the Lisinski testnet for best performance and learn some new skills that'll come in handy when running a full node of the Ethereum mainnet.