For nodes, which are crucial for the underlying infrastructure of blockchain networks, it is paramount to conduct testing using a deterministic chain. This approach ensures that the behavior of the node under test can be predicted and replicated, enhancing the reliability of the testing process.

On the other hand, when it comes to developing wallets, a different testing strategy is employed. Instead of integrating with a live blockchain, which introduces variables and potential points of failure outside the developer's control, wallets can be tested using mockups of the blockchain. These mockups consist of static blocks containing specially crafted transactions. This method allows developers to simulate various scenarios and test functionalities such as transaction signing without the need to connect to a live blockchain's Remote Procedure Call (RPC) interface. By doing so, developers can circumvent the unreliability and unpredictability associated with live blockchain connections, ensuring a more controlled and reliable testing environment.