The @neo4j-labs/temp-dbs JavaScript library provides a way to create temporary, self-cleaning Neo4j databases on the fly using the multi-db feature. This library allows developers to quickly create and expire Neo4j databases ad hoc, making it suitable for lightweight console-based applications and efficient unit tests. The example walkthrough demonstrates how to get started with creating a minimal webapp that leverages the @neo4j-labs/temp-dbs library, including setting up dependencies, configuring environment variables, and creating routes to interact with temporary databases. Additionally, the example shows how to clean up expired databases using a separate script. This library can be used to ease unit testing by providing a convenient way to create and manage temporary Neo4j databases.