Yes, the Hedera source code is open source. You can find it in the official GitHub repository: https://github.com/hashgraph/hedera-services.
We are committed to transparency and open source as core principles. Hedera has contributed the entirety of its source code—encompassing the hashgraph consensus algorithm, core services, and essential tools— to the LF Decentralized Trust, where it lives as the "Hiero" project. For more details about the approach to open source, please refer to:
- Introducing Hiero: https://hedera.com/blog/introducing-hiero-the-foundation-of-the-future
We are continually expanding the scope of our security audits to ensure that all critical components of the Hedera network are thoroughly evaluated. The hashgraph consensus algorithm has been audited by multiple independent firms. You can find the audit report from FP Complete, along with the formal verification (COQ proof) from Carnegie Mellon University, on our Audits and Standards page: https://hedera.com/audits-and-standards. In addition to the hashgraph consensus algorithm, we have conducted extensive audits of the Hedera services codebase. These audits cover a wide range of components, including the modularization of the Java-based code, which focused on the restructuring of the codebase to improve modularity and maintainability.
The Hedera network to date does not have any system or precompile smart contract bytecode maintained by the network. All smart contracts are deployed by users who will employ their own auditing and transparency processes. The Hedera network does offer System contracts, which are address interfaces that support the execution of HAPI code as if they were deployed smart contract functions. Hedera makes reference example Solidity contracts available to enable developers to get started developing at https://github.com/hashgraph/hedera-smart-contracts. However, these contracts are not audited and serve as examples only. While previous audits did not include an assessment of these Solidity smart contract examples, this is planned for future audits.