Apache Fluss, Apache Flink and Iceberg.​

Fraud detection is a mission-critical capability for businesses operating in financial services, e-commerce, and digital payments. Detecting suspicious transactions in real time can prevent significant losses and protect customers. This blog demonstrates how to build a streamhouse that processes bank transactions in real time, detects fraud, and serves data seamlessly across hot (sub‑second latency) and cold (minutes‑latency) layers. Real-time detection and historical analytics are combined, enabling businesses to act quickly while maintaining a complete audit trail.

As software and data engineers, we've witnessed Apache Iceberg revolutionize analytical data lakes with ACID transactions, time travel, and schema evolution. Yet when we try to push Iceberg into real-time workloads such as sub-second streaming queries, high-frequency CDC updates, and primary key semantics, we hit fundamental architectural walls. This blog explores how Fluss × Iceberg integration works and delivers a true real-time lakehouse.

Apache Fluss represents a new architectural approach: the Streamhouse for real-time lakehouses. Instead of stitching together separate streaming and batch systems, the Streamhouse unifies them under a single architecture. In this model, Apache Iceberg continues to serve exactly the role it was designed for: a highly efficient, scalable cold storage layer for analytics, while Fluss fills the missing piece: a hot streaming storage layer with sub-second latency, columnar storage, and built-in primary-key semantics.

After working on Fluss–Iceberg lakehouse integration and deploying this architecture at a massive scale, including Alibaba's 3 PB production deployment processing 40 GB/s, we're ready to share the architectural lessons learned. Specifically, why existing systems fall short, how Fluss and Iceberg naturally complement each other, and what this means for finally building true real-time lakehouses.

🌊 We are excited to announce the official release of Apache Fluss (Incubating) 0.8!

This is our first release under the incubator of the Apache Software Foundation, marking a significant milestone in our journey to provide a robust streaming storage platform for real-time analytics.

Over the past four months, the community has made tremendous progress, delivering nearly 400 commits that push the boundaries of the Streaming Lakehouse ecosystem. This release includes multiple stability optimizations and introduces deeper integrations, performance breakthroughs, and next-generation stream processing capabilities. Highlights:

• 🧊 Enhanced Streaming Lakehouse capabilities with full support for Apache Iceberg and Lance
• ⚡ Introduction of Delta Joins with Flink, a game-changing innovation that redefines efficiency in stream processing by minimizing state and maximizing speed.
• 🔧 Supports hot updates for both cluster configurations and table configurations

Apache Fluss 0.8 marks the beginning of a new era in streaming: real-time, unified, and zero-state, purpose-built to power the next generation of data platforms with low-latency performance, scalability, and architectural simplicity.

Modern data platforms have traditionally relied on two foundational components: a log for durable, ordered event storage and a cache for low-latency access. Common architectures include combinations such as Kafka with Redis, or Debezium feeding changes into a key-value store. While these patterns underpin a significant portion of production infrastructure, they also introduce complexity, fragility, and operational overhead.

Apache Fluss (Incubating) addresses this challenge with an elegant solution: Primary Key Tables (PK Tables). These persistent state tables provide the same semantics as running both a log and a cache, without needing two separate systems. Every write produces a durable log entry and an immediately consistent key-value update. Snapshots and log replay guarantee deterministic recovery, while clients benefit from the simplicity of interacting with one system for reads, writes, and queries.

In this post, we will explore how Fluss PK Tables work, why unifying log and cache into a persistent design is a critical advancement, and how this model resolves long-standing challenges of maintaining consistency across multiple systems.

Streaming Storage More Suitable for Real-Time OLAP​

Introduction​

The Data Development Team of Taobao has built a new generation of real-time data warehouse based on Apache Fluss. Fluss solves the problems of redundant data transfer, difficulties in data profiling, and challenges in large scale stateful workload operations and maintenance. By combining columnar storage with real-time update capabilities, Fluss supports column pruning, key-value point lookups, Delta Join, and seamless lake–stream integration, thereby cutting I/O and compute overhead while enhancing job stability and profiling efficiency.

Already deployed on Taobao’s A/B-testing platform for critical services such as search and recommendation, the system proved its resilience during the 618 Grand Promotion: it handled tens of millions of requests with sub-second latency, lowered resource usage by 30%, and removed more than 100 TB from state storage. Looking ahead, the team will continue to extend Fluss within a Lakehouse architecture and broaden its use across AI-driven workloads.

Fluss stores historical data in a lakehouse storage layer while keeping real-time data in the Fluss server. Its built-in tiering service continuously moves fresh events into the lakehouse, allowing various query engines to analyze both hot and cold data. The real magic happens with Fluss's union-read capability, which lets Flink jobs seamlessly query both the Fluss cluster and the lakehouse for truly integrated real-time processing.

In this hands-on tutorial, we'll walk you through setting up a local Fluss lakehouse environment, running some practical data operations, and getting first-hand experience with the complete Fluss lakehouse architecture. By the end, you'll have a working environment for experimenting with Fluss's powerful data processing capabilities.

On June 5th, Fluss, the next-generation streaming storage project open-sourced and donated by Alibaba, successfully passed the vote and officially became an incubator project of the Apache Software Foundation (ASF). This marks a significant milestone in the development of the Fluss community, symbolizing that the project has entered a new phase that is more open, neutral, and standardized. Moving forward, Fluss will leverage the ASF ecosystem to accelerate the building of a global developer community, continuously driving innovation and adoption of next-generation real-time data infrastructure.

Introduction​

Apache Fluss is a streaming data storage system built for real-time analytics, serving as a low-latency data layer in modern data Lakehouses. It supports sub-second streaming reads and writes, storing data in a columnar format for efficiency, and offers two flexible table types: append-only Log Tables and updatable Primary Key Tables. In practice, this means Fluss can ingest high-throughput event streams (using log tables) while also maintaining up-to-date reference data or state (using primary key tables), a combination ideal for scenarios like IoT, where you might stream sensor readings and look up information for those sensors in real-time, without the need for external K/V stores.

Background​

At the core of Fluss’s Lakehouse architecture sits the Tiering Service: a smart, policy-driven data pipeline that seamlessly bridges your real-time Fluss cluster and your cost-efficient lakehouse storage. It continuously ingests fresh events from the fluss cluster, automatically migrating older or less-frequently accessed data into colder storage tiers without interrupting ongoing queries. By balancing hot, warm, and cold storage according to configurable rules, the Tiering Service ensures that recent data remains instantly queryable while historical records are archived economically.

In this blog post we will take a deep dive and explore how Fluss’s Tiering Service orchestrates data movement, preserves consistency, and empowers scalable, high-performance analytics at optimized costs.

🌊 We are excited to announce the official release of Fluss 0.7!

This version has undergone extensive improvements in stability, architecture, performance optimization, and security, further enhancing its readiness for production environments. Over the past three months, we have completed more than 250 commits, making this release a significant milestone toward becoming a mature, production-grade streaming storage platform.