The previous chapter allowed you to experiment with doing rather than reading about doing, as it effectively demonstrated developing the samples. The preceding chapter offered in-depth facts on the Oracle Blockchain Platform (OBP) and taught the practicalities of translating network topology on OBP, creating network stakeholders, and configuring OBP instances. This concluding chapter delves into chaincode and covers details of chaincode development, including the language section, development tools, and development environment setup. This chapter also focuses on mapping asset models, operations, and developing chaincode functions and interfaces. It details the full life cycle of chaincode, from development to updates, including installation, initiation, testing, and versioning. It also demonstrates the full chaincode with a code base build on Go and Node.js. Endorsement policy, private data collections, and their functioning in concert with chaincode are also illustrated. This chapter also demonstrates chaincode testing via shim and REST endpoints and integrating client apps with business networks using SDK, REST, and events. Finally, it concludes with insights into chaincode, transactions, and channels by experimenting with the monitoring of business via chaincode logs and channel logs. The chapter covers topics such as setting up chaincode development, chaincode development, chaincode deployment, testing chaincode, and integrating client applications with blockchain.