18.0
Arroyo is an open-source distributed stream processing engine for stateful computations on data streams, with sub-second results.
Free planOpen sourceWebAPILinux
Best Stream Processing Software in 2026
When events need to be processed as they arrive, the right software depends on your pipeline and the environment where it runs. Compare deployment models and source connectors, then check how each option handles SQL processing, event-time windows, and stateful processing. Supported languages can help you assess fit for your team, while free-plan availability and paid-from pricing add cost context. Apache Storm,…
27.8
Apache NiFi is free, open-source software for automating data flows between systems, including cybersecurity, observability, event stream, and generative AI pipelines.
Free planOpen sourceWebAPILinux
37.7
Apache Beam is a free, open-source programming model for building data processing pipelines across batch and streaming workloads.
Free planOpen sourceWebAPILinux
- 4
Esper
Esper is a language, compiler, and runtime for complex event processing and streaming analytics in Java and .NET.
Free planOpen sourceAPILinuxmacOSSelf-hosted7.5Free plan - 5
AFL++
AFL++ is a free, coverage-guided fuzzer that changes program inputs and checks whether a target binary reaches previously unseen execution paths.
Free planAndroidLinuxmacOSSelf-hosted7.2From €20,000 a year - 6
Confluent Cloud
Confluent Cloud is a managed data streaming platform built around a serverless Apache Kafka engine.
Free planWebAPILinux7.1From $385 a month - 7
Timeplus
Timeplus is a streaming SQL platform for real-time data pipelines in analytics, telemetry, and AI/ML.
Free planWebAPILinuxmacOS7.1From $199 a month - 8
Materialize
Materialize is a SQL-based live data layer for apps and AI agents.
Free planWebAPILinuxSelf-hosted7.0From $1.50 a year - 9
RisingWave
RisingWave is a distributed SQL streaming platform that ingests, transforms, and serves real-time data.
WebAPILinuxmacOS6.7$0.23 usage-based - 10
Apache Storm
Apache Storm is a free, open-source system for processing unbounded data streams in real time.
Free planWebAPILinuxmacOS6.6Free plan - 11
Feldera
Feldera is an incremental view maintenance engine that keeps SQL views in sync as input data changes, alongside a lakehouse or warehouse.
Free planWebAPILinuxmacOS6.5Free plan - 12
Apache Spark
Apache Spark is a free, open-source engine for large-scale data analytics.
Free planAPILinuxmacOSSelf-hosted6.4Free plan - 13
Kafka Streams
Kafka Streams is a client library for building applications and microservices that read and write data in Kafka clusters.
Free planLinuxmacOSSelf-hostedWindows6.2Free plan - 14
Apache Flink
Apache Flink is a framework and distributed processing engine for stateful computations over bounded and unbounded data streams.
Free planAPILinuxSelf-hosted6.1Free plan - 15
Pathway Live Data Framework
Pathway Live Data Framework is a Python framework for building analytics and AI data pipelines over stored data and live streams.
Free planAPISelf-hosted6.1Free plan - 16
Apache Kafka
Free planAPISelf-hosted6.0Free plan - 17
Apache Samza
Apache Samza is a free, self-hosted framework for processing live data streams and building applications that maintain state.
Free planAPILinuxSelf-hosted6.0Free plan - 18
Quix Streams
Quix Streams is a free, open-source Python library for processing Kafka data and building real-time streaming applications.
Free planLinuxSelf-hosted5.9Free plan - 19
Siddhi
Siddhi is a free, open-source stream and complex event processing engine for building event-driven applications.
APILinuxmacOSSelf-hosted5.9 - 20
Hazelcast Platform
Hazelcast Platform brings a distributed compute engine and fast data store together in one runtime for real-time and AI-driven applications.
APILinuxmacOSSelf-hosted5.8 - 21
Amazon Managed Service for Apache Flink
Amazon Managed Service for Apache Flink runs Apache Flink applications in the cloud to transform and analyze streaming data in real time.
WebAPI5.5 - 22
Apache Heron
Apache Heron is a real-time engine for processing data streams across distributed systems, designed to tolerate faults.
LinuxSelf-hosted5.5 - 23
Timely Dataflow
Timely Dataflow is a free, open-source Rust system for distributed streaming computation and general computation structure.
APISelf-hosted5.3 - 24
Azure Stream Analytics
Azure Stream Analytics is a web service for processing streaming data with stateful processing, SQL processing and event-time windows.
Web5.1 - 25
Google Cloud Dataflow
Google Cloud Dataflow is a cloud-deployed data processing service accessed through the web.
Web4.9