OneLedger is a cross-chain agnostic protocol that focusing on different mechanism integrity to enhance the flexibility, security, heterogeneity, and interoperation of its blockchain and other sidechains. The performance of this blockchain is more impressive and scalable thanks to the practical Byzantine Fault Tolerant mechanism while the design of infrastructure allows the consensus on both OneLedger blockchain and the connected sidechains facilitating the interaction between. The final target of the project is to become an environment for small businesses and enterprises to build their own blockchain with the provided tools and codebase so they can operate more effectively. Besides the competitive advantages, there are still some drawbacks about this project.