As software systems mature, their complexity increases, leading to higher costs in changing and scaling them, making scalability a crucial aspect of enterprise software. This tutorial introduces contract testing with Pact as a solution to make integration testing more scalable and manageable by verifying contracts between dependent API endpoints. Unlike end-to-end testing, which involves multiple systems, contract testing isolates integration points, ensuring messages conform to an agreed-upon contract between consumer and provider services. The tutorial covers setting up Pact for testing HTTP integrations using Node.js and CircleCI to automate tests in a continuous integration pipeline. It details the configuration of consumer and provider tests, illustrating how Pact's contract testing improves maintainability and detects changes in expected responses, thus facilitating seamless communication between microservices. The tutorial emphasizes the ease of integrating automated contract tests into a CI/CD pipeline, enhancing the reliability and efficiency of the development workflow, and concludes with practical steps to set up and run these tests using CircleCI.