Serialization and RPC generated for fifteen languages at once
Serialization Formats
Apache Thrift is a cross-language services framework: an interface definition language and code generator that emit both the serialization code and the RPC client and server for more than a dozen languages, with pluggable protocols and transports underneath.
The wire format is the in-memory format — no decoding step
Serialization Formats
Cap'n Proto is an MIT-licensed binary interchange format and capability-based RPC system from the author of Protocol Buffers version 2, designed so that the encoded bytes are directly usable in memory — there is no parse step between receiving a message and reading a field.
Read fields straight out of the buffer, with no heap at all
Serialization Formats
FlatBuffers is Google's Apache-2.0 cross-platform serialization library, built for performance-critical code: data is accessed directly in the serialized buffer without unpacking, the only memory needed is the buffer itself, and schemas evolve with forwards and backwards compatibility.
The contract layer for the encoding everything already speaks
Serialization Formats
JSON Schema is the vocabulary for describing, validating, and documenting JSON data — the third schema type every major schema registry supports alongside Avro and Protocol Buffers, and the one that requires no new encoding on the wire.
One registry for event schemas and API contracts alike
Schema Registries
Apicurio Registry is an Apache-2.0 registry that stores schemas and API definitions together — Avro, Protobuf, JSON Schema, OpenAPI, AsyncAPI, GraphQL, WSDL and XSD — behind a REST API, with a Confluent-compatible endpoint so existing Kafka clients work unchanged.
A Protobuf registry that rejects breaking changes at push time
Schema Registries
The Buf Schema Registry stores versioned Protobuf modules rather than individual topic schemas: pushes are linted and checked for breaking changes before they reach consumers, generated SDKs are published to native package managers, and a Confluent-compatible endpoint serves Kafka clients.
A serverless schema registry AWS does not charge for
Schema Registries
The AWS Glue Schema Registry is a serverless registry for streaming schemas — Avro, JSON Schema, and Protobuf — with eight compatibility modes, open-source serialisers, and integrations across MSK, Kinesis Data Streams, Managed Service for Apache Flink, and Lambda. AWS's documentation states it is free to use.
Streaming database keeping materialized views always current
Stream Processing
RisingWave is a PostgreSQL-compatible streaming database that maintains materialized views incrementally rather than recomputing them, storing state and tables in object storage so compute and storage scale separately.
Incremental view maintenance with strict serializability
Stream Processing
Materialize incrementally updates SQL results as data arrives rather than recomputing them, built on Timely and Differential Dataflow and reachable over the PostgreSQL wire protocol, with strict serializability by default.
Portable pipeline model that runs on Flink, Spark, or Dataflow
Stream Processing
Apache Beam is a unified programming model for batch and streaming pipelines, written once in Java, Python, or Go and executed by a runner — Flink, Spark, Dataflow, or others — rather than by an engine of its own.
Fully managed Apache Beam runner with autoscaling workers
Stream Processing
Google Cloud Dataflow is a fully managed service that executes Apache Beam pipelines for batch and streaming, provisioning and autoscaling worker VMs automatically and processing every record exactly once by default.
Managed SQL stream processing that also runs on IoT Edge
Stream Processing
Azure Stream Analytics is a fully managed stream processing engine using a SQL dialect extended with temporal constraints, running in the cloud or on IoT Edge with the same tools and query language.
Rust stream processing engine driven entirely by SQL
Stream Processing
Arroyo is a distributed stream processing engine written in Rust that defines pipelines in SQL, performing stateful computation over bounded and unbounded sources with event-time processing and watermarks.
Streaming platform separating serving from storage tiers
Event Streaming
Apache Pulsar is an open-source messaging and streaming platform that splits brokers from storage, keeping segments in Apache BookKeeper so capacity and serving scale independently, with multi-tenancy and geo-replication built in.
Commercial Kafka platform from the team that built it
Event Streaming
Confluent is the commercial data streaming platform built around Apache Kafka by its original creators, sold as self-managed Confluent Platform and as the Confluent Cloud service, and acquired by IBM in March 2026.
AWS-native shard-based streaming with on-demand capacity
Event Streaming
Amazon Kinesis Data Streams is AWS's managed event streaming service, organising data into shards with provisioned or on-demand capacity and integrating directly with the rest of the AWS analytics stack.
Managed messaging with push and pull delivery on Google Cloud
Event Streaming
Google Cloud Pub/Sub is an asynchronous, scalable messaging service that decouples producers from consumers, offering push and pull subscriptions, configurable exactly-once delivery, and roughly 100-millisecond latency.
Managed Azure streaming that speaks the Kafka protocol
Event Streaming
Azure Event Hubs is Microsoft's fully managed event streaming platform, natively supporting the Apache Kafka protocol alongside AMQP and HTTPS so existing Kafka workloads run without code changes or cluster management.
Single-binary messaging with optional JetStream persistence
Event Streaming
NATS is a messaging system distributed as one small Go binary, offering at-most-once core messaging with JetStream adding a persistence layer for at-least-once delivery, replay, and server-side consumer state.
Diskless Kafka-compatible streaming straight to object storage
Event Streaming
WarpStream is a Kafka-compatible streaming platform with no local disks, writing directly to S3-class object storage, and running its stateless agents inside the customer's own cloud account under a bring-your-own-cloud model.
Kafka with its storage layer rebuilt on object storage
Event Streaming
AutoMQ keeps Apache Kafka's compute layer and replaces its storage with cloud object storage, claiming 100% Kafka API compatibility and substantially lower cost by removing multi-replica local disks and cross-zone transfer.
Message broker with flexible routing and append-only streams
Event Streaming
RabbitMQ is a widely deployed open-source message broker built on Erlang/OTP, combining rich queue-based routing with a Streams feature that adds append-only, replayable logs alongside traditional queues.
AWS migration service with ongoing change replication
Change Data Capture
AWS Database Migration Service moves data between relational databases, warehouses, and NoSQL stores, either as a one-time migration or as ongoing replication that keeps a source and target in sync.
Serverless CDC from operational databases into BigQuery
Change Data Capture
Datastream is Google Cloud's serverless change data capture and replication service, streaming changes from Oracle, MySQL, PostgreSQL, SQL Server, MongoDB, and Spanner into BigQuery and Cloud Storage with minimal latency.
Enterprise real-time replication across heterogeneous databases
Change Data Capture
Oracle GoldenGate is a real-time data replication and change data capture platform spanning Oracle and non-Oracle databases, NoSQL stores, warehouses, and messaging systems, available self-managed or as a managed OCI service.
Postgres-specialised CDC, and the engine behind ClickPipes
Change Data Capture
PeerDB is an open-source change data capture engine built specifically for PostgreSQL sources, acquired by ClickHouse in 2024 and kept as a distinct component powering the managed Postgres CDC in ClickPipes.
Postgres changes to queues and streams, exactly once
Change Data Capture
Sequin is an open-source CDC tool that streams PostgreSQL changes to queues, streaming platforms, and webhooks with strict ordering and exactly-once processing, shipped as a Docker image rather than a Postgres extension.
MySQL binlog to JSON change events on Kafka or Kinesis
Change Data Capture
Maxwell's Daemon reads the MySQL binary log and writes row-level changes as JSON to Kafka, Kinesis, and other streaming platforms — a single-purpose CDC process with no framework around it.
Real-time CDC platform with in-flight streaming SQL
Change Data Capture
Striim is a commercial real-time data integration platform combining change data capture with streaming SQL, moving data from operational databases and SaaS applications into warehouses, lakehouses, and Kafka as it changes.
Agentless log-based replication from mainframe to cloud
Change Data Capture
Qlik Replicate is a commercial data replication platform using agentless, log-based change data capture, spanning mainframe and mid-range systems, SAP estates, and modern cloud warehouses without installing software on the source.
Streaming-first data movement with batch and CDC connectors
Batch ELTChange Data Capture
Estuary Flow is a data movement platform built on a streaming core, capturing from databases via CDC and from SaaS APIs, then materialising continuously into warehouses and lakes rather than on a schedule.
Transactional lake format built around upserts and incremental reads
Table Formats
Apache Hudi is an open lakehouse format that pioneered transactional data lakes, offering record-level upserts and deletes, incremental queries, and a choice between copy-on-write and merge-on-read table types.
Lake format with LSM-backed streaming updates and changelogs
Table Formats
Apache Paimon is a lake format unifying batch and streaming, using an LSM tree to absorb high-frequency updates and emitting changelogs so downstream jobs can consume what changed rather than rescanning.
Real-time analytics database for fast slice-and-dice queries
OLAP Engines
Apache Druid is a real-time analytics database combining ideas from data warehouses, time-series databases, and log search systems, with columnar storage, time-based partitioning, and bitmap indexes serving sub-second queries over streaming data.
Real-time OLAP for user-facing analytics at high concurrency
OLAP Engines
Apache Pinot is a distributed real-time OLAP store built to serve analytical queries at very high concurrency with millisecond latency, ingesting directly from streams.
Debezium is an open-source CDC platform that streams row-level changes from databases such as PostgreSQL, MySQL, and MongoDB, typically via Kafka Connect.
Apache Kafka is an open-source distributed log for high-throughput, durable event streaming, with a large ecosystem including Kafka Connect and Kafka Streams.
Apache Flink is an open-source framework for stateful computation over unbounded and bounded data streams, with event-time processing, exactly-once state consistency, and CDC ingestion via Flink CDC.
Kafka-compatible streaming platform in a single binary
Event Streaming
Redpanda is a Kafka API-compatible streaming platform written in C++, shipped as a single binary without ZooKeeper or a JVM, available self-hosted or as a managed cloud.
Compact, typed serialization from the gRPC ecosystem
Serialization Formats
Protocol Buffers (protobuf) is Google's language-neutral, schema-first binary serialization format, ubiquitous in service APIs and increasingly present in event streams.