Parallel integration test execution using PostgreSQL schema isolation

[drnow4u]

Summary

Integration tests currently run sequentially. With 50+ test classes, this results in long feedback cycles.

Problem

Each test class uses TRUNCATE CASCADE for isolation before execution, which prevents parallel runs — concurrent tests would interfere with each other's data in the shared public schema.

On modern multi-core CPUs, sequential test execution leaves most cores idle, failing to utilise available hardware capacity.

Goal

Enable integration test classes to run in parallel without data interference, reducing overall test suite execution time.

Context

• Spring Boot integration tests (@SpringBootTest)
• All test classes share a single Spring application context
• PostgreSQL
• Flyway for schema migrations
• ~50+ integration test classes, each setting up and tearing down data via JDBC

[philwebb]

I'm sure what action we can take in Spring Boot for this. It sounds like you want to run tests in parallel, but also not have contention against a single database. Are you suggesting some kind of pool for test databases? Can you provide some more details about how you see a potential solution working?