What is Apache Pulsar?

Apache Pulsar is an open-source, cloud-native pub-sub messaging and streaming platform that has gained popularity since its open-sourcing in 2016. It combines the best features of traditional messaging systems like RabbitMQ with those of pub-sub systems like Kafka. Pulsar is highly scalable and can handle demanding data movement use cases, making it a perfect fit for distributed applications, serverless, and microservices architectures. Some key advantages over Kafka include better price and performance, as found by market research firm GigaOm. Apache Pulsar's multi-layer architecture allows new layers to be added, supporting features like tiered storage, geo-replication, and IO connectors. It also supports multiple subscription types and offers low, consistent latency at high throughput. Use cases for Pulsar include real-time messaging, event sourcing, delayed delivery, and real-time data processing with functions.