Testcontainers

Testcontainers is an open-source library providing throwaway, lightweight instances of common test dependencies (databases, message brokers, web browsers) via Docker containers.

Testcontainers revolutionizes integration testing by defining real service dependencies as code: no more mocks or in-memory databases. The library leverages Docker to provision isolated, ephemeral instances of services like PostgreSQL, Kafka, or Selenium web browsers for each test run. This ensures reliable, repeatable testing across environments (local IDE to CI/CD pipelines). It supports multiple major languages, including Java, Go, .NET, and Python, allowing teams to confidently test against the exact same service versions used in production.

https://www.testcontainers.com/