The ASF is made up of over 100 top level projects that cover a wide range of technologies. Chances are if you are looking for a rewarding experience in Open Source, you are going to find it here.
Apache Lucene is a high-performance, full-featured text search engine library
Apache Lucene is a high-performance, full-featured text search engine library written entirely in Java. It is a technology suitable for nearly any application that requires full-text search, especially cross-platform.
AMQP enterprise messaging implementation.
Apache Qpid implements the latest AMQP specification, the first open standard for enterprise messaging, and provides transaction management, queuing, distribution, security, management, clustering, federation and heterogeneous multi-platform support and a lot more.
Apache Kafka is a distributed, fault tolerant, publish-subscribe messaging.
A single Kafka broker can handle hundreds of megabytes of reads and writes per second from thousands of clients. Kafka is designed to allow a single cluster to serve as the central data backbone for a large organization. It can be elastically and transparently expanded without downtime. Data streams are partitioned and spread over a cluster of machines to allow data streams larger than the capability of any single machine and to allow clusters of co-ordinated consumers. Kafka has a modern cluster-centric design that offers strong durability and fault-tolerance guarantees. Messages are persisted on disk and replicated within the cluster...