Summary

The table below lists network upgrades, commonly known as hard forks, in the cryptocurrency world. These updates are mandatory for all nodes and help to keep the network secure and up-to-date. For a comprehensive list of past and frequent core updates, please refer to the Github releases  or Git commits .

V6

This upgrade focuses on improving the smart contract system with new features and the BlockDAG structure to enhance the overall performance and scalability of the network.

Contract Events will be introduced to allow smart contracts to emit events that can be easily tracked and consumed by other contracts. This will enable more complex interactions between contracts and allow developers to build more sophisticated applications on top of the XELIS blockchain.

BlockDAG will see optimizations, including a new algorithm to compute the cumulative difficulty for better chain selection and improved handling of orphaned blocks to enhance network stability and reduce the chances of forks.

Side blocks rewards are also updated to match main blocks rewards, which will incentivize miners to include honest blocks in the DAG and improve the overall security and decentralization of the network.

V5

This upgrade focuses on improving the transaction base fee system to make it more efficient and fair for users. The new system will be more dynamic and responsive to network conditions, ensuring that users pay a fair fee for their transactions while also preventing fee spikes during periods of high demand.

V4

BlockDAG improvements and various bug fixes. More security checks added to enhance network stability.

Reference TX from a miner in the unstable height is now rejected from being spend until the block is stable, increasing the stability of the network during DAG ordering and reducing the risk of orphaned blocks.

V3

Smart Contracts have been enabled on the network along a reduction from 15s to 5s in average block time. The new dynamic base fee system has been enabled partially.

Mining has been improved with PoW V3 for a better egalitarian algorithm increasing CPU performance and reducing GPU and FPGA parallelism.

V2

A short notice important network upgrade. Introduces several key improvements and a security patch.

MultiSig A highly anticipated and essential feature for the ecosystem. The network now supports multi-signature setups, enabling greater security and new possibilities for users and developers.

Key use cases include:

• Governance & financial security: Collateralized multisig wallets.
• 2FA auth-like feature: Setup two keys to authorize transactions to protect your funds.
• Public view wallet: Allow others to view hidden wallet funds without the ability to access or move them.

P2P DH (Diffie-Hellman)
A new key exchange protocol to enable more secure peer-to-peer communication. Both parties independently generate a shared key using private and public keys, ensuring that transmitted data is encrypted and immune to eavesdropping.

Security Patch
Details of the patch are not disclosed at this time.

Additional improvements
This upgrade also include various other enhancements, such as the ability to track burned supply, and more.

V1

This is the first network upgrade. It was aimed at adjusting the minning algorithm to be more egalitarian across devices and enchance resistance against FPGAs.

The name of the new POW algorithm is XelisHashV2 .

Additionally, prior to this upgrade, we could not get an accurate estimate of the current hashrate. The first algorithm was susceptible of producing low-bits hash, resulting in higher than expected reported network hashrate. This issue was inherently resolved by using the new algorithm.

We’ve also increase the extra data size limit per TX from 1 KB to 32 KB. This allows to integrate more data in a single transaction, such as a document or a picture. Note that the limit per transfer in a TX stays at 1 KB.

The difficulty algorithm was also adjusted to be less aggressive and smoother. This will help to reduce the impact of hashrate fluctuations on the network and reduce orphans blocks.

Lasty, changes were made to the internal storage of the versioned balances to fix orphan transactions. We discovered a front-running problem that could occur when building several TXs not all executed in the same block, causing them to become orphaned because the output balance was not updated accordingly.

The upgrade was scheduled to take place at block height 434100, approximately on July 11th, 2024.

V0

This is the first version of the blockchain. It was launched on April 20th, 2024, at block height 0.