CloudNativePG versus YugabyteDB: Choosing the Best Database Architecture for  Cloud-Native Apps

In this blog, Yugabyte expert Chris Smith shares his recent experience at KubeCon 2025 and compares CloudNativePG to YugabyteDB, focusing on how each database approaches high availability, scalability, and cloud-native architecture. He also explores the benefits of a truly distributed architecture and why it matters in modern application development.

A Revolution in Stateful Workloads

It was incredible to observe a significant change in people’s attitudes towards stateful workloads on Kubernetes at KubeCon 2025 in London.

At previous KubeCons, most people were using Kubernetes for stateless workloads, i.e. application services, and only a small number were running services like Kafka or their databases. This year, the pendulum had overwhelmingly swung in the opposite direction, and it seemed as if everyone had started to experiment with running stateful workloads on Kubernetes. KubeCon attendees are admittedly a biased sample, but the change was significant, and is backed up by the CNCF, which claims that “74% of organizations reported using containers to manage stateful applications.”

When considering stateful workloads on Kubernetes, PostgreSQL is frequently the first choice. Often starting their journey with the CloudNativePG operator for PostgreSQL, many database architects then consider genuinely distributed architectures, beyond just running PostgreSQL in a container. The conversation naturally shifts to distributed SQL – a database architecture that can genuinely meet the demands of modern scalable applications.

CloudNativePG: A First Step When Running PostgreSQL on Kubernetes

CloudNativePG is an open-source Kubernetes operator that manages PostgreSQL in a cloud-native way. It’s CNCF-Sandbox and is designed to support automated deployments and day-2 operations for PostgreSQL in Kubernetes.

Key Features of CloudNativePG:

• Kubernetes operator for PostgreSQL
• Built-in high availability using streaming replication (primary/replica model)
• Automated backups
• Works with standard PostgreSQL tooling

How It Works:

CloudNativePG deploys a primary-secondary setup. One node is the primary, and others are read-only replicas using physical streaming replication. Failover mechanisms promote a secondary replica to become the primary one if the active node fails.

Limitations:

• Not horizontally scalable for writes: writes go to a single node (the primary).
• Failover is reactive, not proactive – there’s downtime during failover.
• Lacks multi-region capabilities.
• Read-only replicas are asynchronous (so in case of primary failure, there can be data loss; i.e. RPO is not zero)

YugabyteDB: Distributed PostgreSQL by Design

YugabyteDB is an open-source, high-performance, strongly consistent distributed SQL database. It delivers PostgreSQL compatibility at the query layer whilst offering the horizontal scalability and fault tolerance of a NoSQL system – the best of both worlds.

Key Features of YugabyteDB:

• Kubernetes operator for YugabyteDB.
• Truly distributed, shared-nothing architecture
• Built-in resilience, including self-healing in the event of pod or availability zone failure.
• Linear horizontal scalability for reads and writes.
• Raft-based consensus for synchronous replication and failover.
• Automatic sharding and rebalancing.
• Automated backups.
• Works with standard PostgreSQL tooling.
• Multi availability-zone awareness, rolling upgrades, and pod-level auto-healing
• Built-in multi-region and geo-distributed support.

How It Works:

YugabyteDB uses a distributed storage engine, with PostgreSQL as the query layer (which is also distributed). Data is automatically sharded across nodes. Each shard (known as a tablet) has a Raft leader and followers for strong consistency and resilience in the event of failure.

All nodes can handle reads and writes, and leadership can dynamically shift. This eliminates the single-writer bottleneck in regular Postgres and hence in CloudNativePG.

Head-to-Head Comparison

Why Distributed Architecture Matters

A genuinely distributed database like YugabyteDB offers compelling benefits for modern, cloud-native applications:

1. Elastic Scalability

• Scale reads and writes simply by adding nodes.
• No need for complex sharding logic or third-party proxies.

2. High Availability and Resilience

• Data replicated synchronously using Raft.
• Resilient in the event of a failure with zero data loss.
• Self-healing.

3. Global Deployments

• Multi-region awareness built-in.
• Serves users close to their geography, while ensuring consistency and compliance.

4. Operational Simplicity

• No primary-secondary promotion scripts.
• No managing physical replication lag.
• Built-in rebalancing and orchestration.

5. Developer Productivity

• Full PostgreSQL compatibility, as evidenced by the Postgres Compatibility Index, with the advantages of a distributed system.
• ACID transactions, joins, subqueries, and rich indexing – all scaled out.

Conclusion

CloudNativePG makes it easy to get started with PostgreSQL on Kubernetes. However, it is still constrained by the inherent limitations of PostgreSQL’s monolithic architecture.

YugabyteDB takes a fundamentally different approach. By blending PostgreSQL’s query language with a distributed, fault-tolerant storage layer, it delivers the best of both worlds: rich SQL capabilities, and cloud-native scalability and resilience.

If your application requires write scalability, ultra-resilience, or just needs to avoid the limitations of a single-node database architecture, YugabyteDB offers a future-proof solution for cloud-native applications.

Schedule a demo to see YugabyteDB in action, or check out the latest exciting new features, including YugabyteDB’s first Agentic AI application and extensible vector search.