PgDog

Overview

PgDog is a PostgreSQL proxy for teams that need connection pooling, replica routing or sharding without changing their applications. Its breadth is the draw; the trade-offs are an AGPL-3.0 license and an unsigned macOS binary.

As a free, open-source option, PgDog is compelling for teams prepared to operate database infrastructure themselves. It covers more than connection pooling, but its PostgreSQL focus and license make it a deliberate infrastructure choice rather than a general-purpose database layer.

For a broader category comparison, see Database Proxy Software.

Key features

Pooling and routing

PgDog multiplexes thousands of application connections over fewer PostgreSQL server connections, while retaining support for SET, LISTEN/NOTIFY and advisory locks. That combination can reduce pressure from connection-heavy applications without giving up those session behaviors. It routes reads across replicas and writes to the primary; health checks and failover detection help keep routing aligned with database availability.

Sharding and data movement

Queries with sharding keys can be sent to the relevant shard, and queries without a key can run across databases in parallel. Cross-shard transactions use PostgreSQL prepared transactions and two-phase commit, with automatic rollback on errors. That is useful for workloads that cannot be neatly confined to one shard, though it adds transactional coordination to the architecture.

For online resharding, PgDog copies data and streams row changes to another database while query traffic continues. This gives teams a path to move data without pausing queries. Enterprise insights include Prometheus and OTEL exporters and Incident.io alert integration. Enterprise access controls include SSO, and credentials can be encrypted at rest in supported environments such as Kubernetes or AWS Secrets Manager.

Pricing

Open source: free. The software is free and open source under AGPL-3.0, with no paid-plan quota or seat cap stated. The license deserves attention: internal use does not require sharing source code, but teams should assess the terms for their own distribution and deployment.

Enterprise: custom pricing. It includes a production control plane, insights, dedicated Slack support, architecture reviews and SLA-backed support with a promised response within 15 minutes. This is the fit for organizations that want operational support and enterprise capabilities; the open-source plan avoids a subscription but does not include those enterprise services.

Platforms

PgDog supports Linux, macOS, Windows and self-hosted deployment. Deployment routes include Kubernetes Helm, Docker, AWS ECS Terraform, pre-built binaries and source builds. Pre-built releases cover Linux arm64 and amd64, Apple Silicon Mac and Debian packages; the macOS binary is unsigned, which is a practical installation caveat for Mac users. The product is PostgreSQL-specific.

Who it's for

PgDog suits PostgreSQL teams that need to scale connections, distribute reads or introduce sharding while keeping application changes to a minimum. Its multiple deployment paths suit organizations with existing infrastructure practices, and the enterprise support package may appeal to production teams that want a defined response commitment.

It is less suitable for teams seeking a managed, general-purpose database service, or those unwilling to take on AGPL-3.0 review and self-hosted operations. Mac users should also be comfortable handling an unsigned binary.

Pros and cons

• Pros: Pooling, replica routing, sharding and online resharding in one PostgreSQL-focused layer, reducing the need to assemble separate tools for these jobs.
• Pros: Queries without a shard key can run across databases in parallel, and cross-shard transactions include automatic rollback on errors.
• Pros: Free open-source use and several deployment routes, from containers and Kubernetes to binaries and source.
• Cons: AGPL-3.0 requires license review, particularly for teams distributing or modifying the software.
• Cons: The macOS binary is unsigned, adding friction for users who prefer signed installers.
• Cons: Enterprise support and its production control plane require custom pricing, so those services do not have a predictable published cost.

Alternatives

For a PostgreSQL connection pool with a BSD-3-Clause license, consider pgagroal; it is a narrower fit if pooling is the main requirement. PgBouncer is another free, self-hosted option when a source release and a more focused pooling choice are preferable to PgDog’s combined routing and sharding scope.

Choose ShardingSphere-Proxy if its open-source binary distribution and Docker or Helm deployment are the deciding factors. MySQL is an alternative for teams considering a database platform with SQL and NoSQL applications and replication and high-availability components. OceanBase Database offers an open-source distributed database with full kernel capabilities for teams looking beyond a PostgreSQL proxy.

TiCDC is a free option to consider when evaluating its open-source change-data-capture offering. TurbineProxy is another free, Apache-2.0 proxy option with no per-query fees. Amazon RDS is a paid database service with a free-tier option for teams considering a hosted service instead of a self-hosted proxy.

Verdict

Choose PgDog if your team runs PostgreSQL and wants one free, self-hosted layer for pooling, read balancing and sharding, with online resharding as workloads evolve. Its strongest case is the breadth of scaling features without requiring application changes. Look elsewhere if AGPL-3.0 is a poor fit, if you need a managed database service, or if an unsigned macOS binary is a blocker.