Companion code for a series of posts on ankurm.com covering Spring Data integrations on Spring Boot 4.1 / JDK 25. Each top-level directory is one module, one post, independently runnable.

Module	Post	Stack
`time-series/`	Time-Series Data in Java: QuestDB vs InfluxDB vs TimescaleDB	QuestDB 10.0.1, InfluxDB 3 Core 3.12.0, TimescaleDB 2.25.1 (PG17)
`mongodb/`	Spring Boot 4 with MongoDB: Spring Data MongoDB, Aggregations and Transactions	MongoDB 9.0.2 single-node replica set, Spring Data MongoDB
`elasticsearch/`	Full-Text Search with Spring Data Elasticsearch on Spring Boot 4	Elasticsearch 9.4.8, Spring Data Elasticsearch 6.1.1
`distributed-cache/`	Distributed Caching in Spring Boot: Hazelcast vs Infinispan vs Redis	Hazelcast 5.5.0 (embedded), Infinispan 16.1.4 (embedded), Redis 8.8.3 (Testcontainers)

Each module has its own pom.xml, a docker-compose.yml for its backing services, and a docs/output/ directory holding the real, re-runnable transcripts that every number quoted in its post traces back to. There are no narrative doc chapters here — the deeper material for each post lives in accordions inside the post itself.

Build and test each module from inside its own directory, e.g.:

cd time-series
source scripts/services-up.sh   # starts QuestDB, InfluxDB 3, TimescaleDB
mvn test