pg-mem
In-memory PostgreSQL instance for testing.
Pricing
Free tier
Flat rate
Adoption
↘CoolingLicense
Open Source
Data freshness
Aging · Jun 8, 2026Overview
What is pg-mem?
Pg-mem provides an in-memory PostgreSQL database instance specifically designed to facilitate efficient and isolated unit tests. It helps developers ensure their applications interact correctly with the database without the overhead of setting up a real PostgreSQL server.
Key differentiator
“Pg-mem stands out by offering an in-memory PostgreSQL instance specifically tailored for unit tests, making it easier and faster to test database interactions without the overhead of setting up a real server.”
Capability profile
Capability Radar
Honest assessment
Strengths & Weaknesses
↑ Strengths
↓ Weaknesses
API requires Python-specific patterns, TypeScript SDK is community-maintained
Primary focus on JavaScript and TypeScript ecosystems with limited direct support for other languages
In-memory storage can lead to performance bottlenecks when testing large datasets or complex queries
Documentation is sparse on handling edge cases and advanced features, leading to trial-and-error development
Fit analysis
Who is it for?
✓ Best for
Java teams needing fast and isolated unit tests for PostgreSQL interactions
Developers who want to avoid setting up a real PostgreSQL server for testing purposes
✕ Not a fit for
Projects that require complex database operations beyond basic CRUD
Teams working with languages other than Java, as support is limited
Cost structure
Pricing
Free Tier
Available
Open source — free to use
Starts at
$0
Model
Flat rate
Enterprise
None
Performance benchmarks
How Fast Is It?
Ecosystem
Relationships
Integrations
Next step
Get Started with pg-mem
Step-by-step setup guide with code examples and common gotchas.