Zilliqa

Before ZIL had a market, the founders were trying to turn database sharding into a blockchain protocol. Early documents put Xinshu Dong in charge of the company, Yaoqi Jia over technology, Amrit Kumar over research and Prateek Saxena as scientific adviser. The team says the theory began in a 2015 paper; by June 2017 the effort had become Zilliqa, and its August whitepaper promised throughput that would grow as more miners joined.

Their design split the mining network into smaller groups that processed transactions in parallel. A Directory Service committee assigned nodes and assembled results, proof of work established identities, and practical Byzantine fault tolerance committed blocks. The wager was specific: parallelism would relieve congestion without making every node execute every transaction.

Mainnet opened on January 31, 2019, but it did not yet offer the complete application platform advertised during development. Smart contracts were activated on June 10. That gap matters because Zilliqa’s second invention was Scilla, a language that separates pure computation from the transitions that read state, write state and send messages.

The restriction was deliberate. By making effects explicit and limiting hard-to-analyse behavior, the language was meant to make contracts easier to reason about and formally verify. It could prevent some programming mistakes; it could not make applications infallible. Zilliqa had chosen a safer but unfamiliar language just as Ethereum’s Solidity tooling was becoming the default elsewhere.

Zilliqa added EVM compatibility in April 2023 so Solidity developers and MetaMask users could enter without adopting Scilla first. In the same year, low shard usage and faster block production created a different engineering problem. gZIL governance approved active reward control and temporary desharding ahead of the next architecture.

On December 18, incomplete microblocks reached only part of the network. Nodes calculated different root hashes, consensus lost enough votes to stop, and recovery code failed to activate; block production returned only after a restart. Version 9.3.0 arrived on January 3, 2024 with one shard. The chain famous for operational sharding had removed it to gain efficiency and reliability while its replacement was being built.

The 2024 redesign exchanged proof-of-work identity selection and PBFT for proof of stake and Pipelined Fast-HotStuff. It made EVM execution native, initially kept compatibility for migrated Scilla state, and proposed customizable x-shards rather than the old fixed shard layout. Aventurine imported historical state into a proto-mainnet in December 2024; the production migration occurred at block 4,770,088 on June 23, 2025.

Current RPC answers show the new chain running as chain ID 0x8001 with one shard. That is evidence of a live zq2 mainnet, not evidence that the proposed x-shard ecosystem is already deployed. The old balances and transaction history survived inside a new consensus system, while legacy staking users had to withdraw and delegate again through EVM contracts.

A defect present in every release of the Zilliqa Ledger app copied the wrong 32 bytes when creating Schnorr signatures. Eight zero-padding bytes remained and 64 bits of entropy disappeared. From four or more public signatures, an attacker could reconstruct a private key. Theft began on March 4, 2026 and went unnoticed until KuCoin reported anomalous withdrawals on July 19.

The proven loss was at least 683,130,969.66 ZIL; 6,772 accounts were known to be exposed and 51 were drained. Zilliqa disabled all legacy transaction functionality on July 20, preventing further use of that vulnerable path but also freezing innocent legacy holders. A September 2 hard fork moved the first ten exchange partners to EVM addresses. At review, the retail zero-knowledge migration tool and a second exchange batch were still pending, and a proposed compensation mint had not yet reached a published vote. The incident finished what the protocol migration had left open: the legacy execution path was being retired, not repaired.