General questions

What does “Exonum” mean?

Exonum takes its name from the word "Exonumia". Exonumia are items representing value that are traditionally used to engage in a diverse marketplace.

We chose to name our platform Exonum because you can use it to represent, store, exchange and secure anything of value — any digital asset.

On which platform does Exonum run?

Exonum has been optimized for Linux, MacOS and Windows machines.

What license type do you use?

Exonum is published under an Apache 2.0 license. You are free to create almost anything you want with Exonum — just make sure to credit The Bitfury Group/Exonum.

How can I request Exonum support?

Please send all support requests to Stackoverflow and Gitter. We are here to help, and we want to share anything we learn with the entire developer community.

For IT Professionals

Does Exonum support smart contracts?

Yes! Exonum was designed to handle smart-contracts. Just like other smart-contract platforms, Exonum-based smart contracts represent business logic that can capably add to a blockchain immediately. Exonum-based smart contracts also have the highest performance in terms of transaction processing, able to handle up to 5,000 transactions per second with an unprecedented 0.5 seconds of clearing time and up to 15,000 transactions per second in custom situations.

However, your system administrators must review all smart-contracts written on Exonum before they are publicly deployed. Contracts are written in Rust and are embedded directly into the code of blockchain nodes. This design guarantees memory safety and ensures smart contracts are optimized for speed.

Where are blockchain configuration and the list of validators stored?

In case the genesis block is absent, the blockchain gets configuration from the config file. If the genesis block has already been formed, then the blockchain reads configuration from said genesis block.

Is it possible to implement Exonum-based solutions containing several units at once, for example those similar to peercoin/peershares?

In principal there is a possibility to realize several units based on Exonum simultaneously due to availability of services (analogous to smart-contracts). However, for this purpose currently the developers will have to exclusively realize all high-level interactions between such services.

Is there a possibility to use Exonum with precompiled clients (such as bitcoin, ethereum wallets, etc.) for MacOS, Windows, Linux?

Currently light client is realized with Node.js only. It is, however, scheduled to provide the client in other languages for the purpose of integration into applications.

How can I contribute?

Exonum is open source and can be found on GitHub, so feel free to participate.

What is the direction of the project development?

Very soon we are going to introduce Java bindings and platform-independent interface description to make Exonum more developer-friendly. Please visit the documentation to study our roadmap.

For Business

Is use of Exonum payable?

Exonum provides an anchoring service which makes it impossible to revise the transaction history. The essence of the service is that a hash of the entire blockchain state is periodically included ("anchored") to the public source (Bitcoin Blockchain). Enclosure of a new transaction into the Bitcoin Blockchain requires payment of a fee. Said fee is paid in bitcoins.

Is it possible to integrate Exonum-based token into a stock exchange?

Currently integration of the Exonum-based ICO into the stock exchange is not provided. At the same time, principally, such opportunity exists and may be realized by developers.

How to become Exonum Partner?

Send us an email at

Does Exonum have built-in cryptocurrency?

We designed Exonum to be as flexible as possible. You can design your Exonum Blockchain to have a token or coin, or you can create a permissioned blockchain without one. Just in case, we have included a tutorial on how to create your own Exonum Blockchain cryptocurrency.

Are there any Exonum-based blockchain solutions for technical department internal service/state enterprises/banking service/etc.?

Our team is building a horizontal solution that could be used by technical specialists to elaborate individual specialized software. At the same time we're exploring use cases for Exonum platform to accumulate the common parts that should be incorporated into Core.